UltraScape Flowpoint Smooth Rapid Set External Paving Grout - Charcoal
About the product
UltraScape Flowpoint Smooth Paving Grout – Charcoal
"Fine-Aggregate Flowable Grout for Porcelain, Granite Setts & Darker Natural Stone — Joints from 3mm, Sets in 15 Minutes, Lasts Up to 40 Years"
UltraScape Flowpoint Smooth Charcoal combines a finer aggregate finish (joints from 3mm) with a bold charcoal tone — the ideal choice for charcoal or grey porcelain, granite setts, slate and darker natural stones where a defined, colour-matched joint is needed. It meets BS 7533 standards, achieves a compressive strength of 49.6N/mm², resists weed growth, and lasts up to 40 years. Supplied in 25kg showerproof bags, sets in 15 minutes, and can be applied in light rain.
For best results, use a neoprene squeegee for a clean, stain-free application. A temporary sealer such as Tile Rite Patio Prep Temporary Sealer is highly recommended for porous or darker stones to prevent grout haze and staining.
Ideal for: charcoal or grey porcelain (joints from 3mm), granite setts, slate, darker sandstone, Indian Stone, Yorkstone, clay pavers and concrete flags. Also suitable for darker limestone when used with a temporary pre-sealer.
Also available in Natural Grey. For pale natural stone and porcelain in a colour-matched tone, see Flowpoint Premium Smooth Limestone, Stone Grey and Yorkstone.
Coverage Guide (approximate)
- Porcelain (600×900, 5×20mm joints): 1 bag ≈ 30m²
- Natural Stone (mixed pack): 1 bag ≈ 12–20m²
- Granite Setts: 1 bag ≈ 1.5–2m²
Use our calculator below for a precise estimate based on your patio size and joint width.
Got a question about Flowpoint Smooth? See our Flowpoint FAQs, download the technical datasheet (PDF), or contact us. Alternatively, call 0330 122 1025 — we're always happy to help.
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UltraScape Flowpoint Smooth Rapid Set External Paving Grout - Charcoal
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For Highlands, Guernsey, Jersey, Isle of Man, and Isle of Wight – call 0330 122 1025.
See full delivery info →
For Highlands, Guernsey, Jersey, Isle of Man, and Isle of Wight – call 0330 122 1025.
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Flowpoint Smooth Charcoal — Full Technical Information
Product Overview
UltraScape Flowpoint Smooth Charcoal is a rapid-setting, flowable, cement-based paving grout with a finer aggregate finish for external use. Its finer particle size allows it to fill joints from just 3mm — making it the preferred choice over Flowpoint Standard for porcelain paving, smooth natural stone, and any application requiring a tighter joint. It conforms to BS 7533 and delivers the same proven performance as the wider Flowpoint range, in a bold charcoal tone suited to darker stones and contemporary paving schemes. Approved for use on the London Underground and Overground, and NBS Source registered.
Performance Data
| Property | Value |
|---|---|
| Classification | BS 7533 |
| Compressive strength | 49.6N/mm² |
| Bond strength | Exceptional |
| Shrinkage | Shrinkage compensated |
| Initial set | 15 minutes at 20°C |
| Open to foot traffic | 1 hour |
| Open to vehicular traffic | 4 hours |
| Expected service life | Up to 40 years |
| Permeability | Non-permeable (impermeable bed required) |
| Weather resistance | Can be applied in light rain |
| Frost resistance | Do not apply below 3°C or if frost expected within 24 hours |
Application Data
| Property | Value |
|---|---|
| Water requirement | 4.25 litres per 25kg bag |
| Mixing time | 3–5 minutes |
| Working time after mixing | Approx. 4 minutes — mix one bag at a time |
| Joint width | 3–50mm |
| Joint depth | 20–200mm (single application) |
| Supply format | 25kg showerproof bags (pre-mixed dry-pack — just add water) |
| Colours available | Charcoal & Natural Grey |
Coverage Guide (approximate, per 25kg bag)
| Paving Type | Approximate Coverage |
|---|---|
| Porcelain Paving (600×900, 5×20mm joints) | approx. 30m² |
| Natural Stone (mixed pack) | 12–20m² |
| Granite Setts | 1.5–2m² |
Coverage varies depending on joint width, depth, stone size, surface absorption and wastage. Use the Flowpoint Calculator on this page for an accurate estimate.
Suitable Substrates
- Charcoal or grey porcelain (joints from 3mm)
- Granite setts
- Slate
- Darker sandstone and Indian Stone
- Yorkstone
- Clay pavers
- Concrete flags
- Limestone (including darker limestone when used with a temporary pre-sealer)
Note: Flowpoint Smooth is not recommended for use on some darker limestones (e.g. black limestone) without a temporary pre-sealer, as it may cause slight oxidisation. Contact us for advice on your specific stone.
Approvals & Certifications
- Conforms to BS 7533
- Approved for use on the London Underground and London Overground
- NBS Source registered
- Part of the Flowpoint range — in use for over 25 years across public realm, commercial and domestic projects worldwide
Storage & Shelf Life
- Shelf life: 8 months from date of manufacture (printed on the white strip on the side of the bag)
- Store in a cool, dry, frost-free area in unopened, sealed bags, clear of the ground
- Using after the declared storage period may increase the risk of an allergic reaction
Health & Safety
- Contains cement — wear appropriate PPE including gloves and eye protection
- Wet cement can cause serious skin burns — avoid prolonged skin contact
- Wash hands and exposed skin thoroughly after use
- Keep out of reach of children
- Full Safety Data Sheet (SDS) available on request or from the UltraScape website
For the full technical datasheet, download the PDF here. For project-specific advice, get in touch or call us on 0330 122 1025.
How to Mix & Apply UltraScape Flowpoint Smooth Paving Grout
Step 1 — Preparation
There are two approaches depending on whether you are using a temporary pre-grout sealer or not:
Without a temporary pre-sealer (standard method):
- Ensure joints are clean and free from debris, dust and loose material.
- Thoroughly pre-soak the paving surface and joints with water — the paving must be properly wet before you begin.
- Then remove all standing or ponded water from the surface and from within the joints — a leaf blower is ideal for this. The paving should be damp, not waterlogged. This is the key step: the paving needs to be wet enough to prevent the grout drying out too quickly, but any excess standing water will over-dilute the mix and weaken the joint.
- Keep the surface moist throughout application by misting with a soft spray of water as you work — do not allow it to dry out.
With a temporary pre-grout sealer (e.g. Tile Rite Patio Prep or Nexus ProJoint Pre-Grout):
- Apply the temporary sealer to the paving in advance and allow it to dry as per the product instructions.
- Do not pre-soak the paving with water. The temporary sealer acts as the protective barrier at this stage — water is not required until clean-down.
- Remove any standing water from the joints using a leaf blower before grouting begins.
- Always carry out a small trial area first to ensure compatibility with your stone type.
Step 2 — Mixing
- Add 4.25 litres of clean water per 25kg bag into a clean bucket or mixing vessel.
- Gradually add the Flowpoint Smooth powder to the water (not the other way around) and mix for 3–5 minutes until a smooth, lump-free, pourable consistency is achieved. Use a slow-speed drill and paddle mixer for best results.
- Only mix what you can apply in approximately 4 minutes — do not store liquid mortar.
- Never remix or add extra water once mixed. Doing so will weaken the final joint and may cause staining.
Step 3 — Application
- Pour the mixed grout directly onto the paving surface.
- Using a neoprene squeegee, carefully force the mortar into the joints, working it across the surface repeatedly. The finer aggregate of Flowpoint Smooth flows particularly well into narrow joints — work methodically to ensure all joints are fully filled. Top up any joints where the mortar has slumped after initial placement.
- Use the squeegee to remove as much excess mortar as possible from the surface as you go.
- If not using a temporary pre-sealer, keep the surface constantly moist using a soft spray of water throughout application. If using a pre-sealer, water is not required until clean-down.
- Once the jointing mortar has reached its initial set and hardened sufficiently, clean the paving surface thoroughly using a brush and copious amounts of clean water. No mortar must be allowed to remain on the surface of the paving.
- Wash all tools frequently during application.
Step 4 — Trafficking
- Foot traffic: after 1 hour (at 20°C)
- Vehicular traffic: after 4 hours (at 20°C)
- Cool temperatures retard set; warm temperatures accelerate it. Avoid applying in direct sunlight or during frost.
Technical Specification (Mixing Tab Summary)
| Property | Value |
|---|---|
| Water requirement | 4.25 litres per 25kg bag |
| Mixing time | 3–5 minutes |
| Working time after mixing | Approx. 4 minutes |
| Initial set | 15 minutes at 20°C |
| Open to foot traffic | 1 hour |
| Open to vehicular traffic | 4 hours |
| Joint width | 3–50mm |
| Joint depth | 20–200mm (single application) |
Important Precautions
- Wear appropriate PPE — avoid skin and eye contact. Wet cement can cause serious burns to the skin.
- Never remix or add extra water to the mix once it has been prepared.
- If you are not using one of UltraScape's pre-bagged bedding mortars, take care when selecting aggregates or sands for your site-batched bedding mortar. Some bedding mortars can leach pigment into the Flowpoint, causing variation in joint colour. If in doubt, give us a call — we're happy to advise.
- Do not apply in temperatures below 3°C or if frost is expected within 24 hours.
- Do not apply in direct sunlight — the product will set rapidly and may be difficult to clean down.
- Store in a cool, dry, frost-free area. Shelf life: 8 months from date of manufacture (printed on the white strip on the side of the bag).
About the product
UltraScape Flowpoint Smooth Paving Grout – Charcoal
"Fine-Aggregate Flowable Grout for Porcelain, Granite Setts & Darker Natural Stone — Joints from 3mm, Sets in 15 Minutes, Lasts Up to 40 Years"
UltraScape Flowpoint Smooth Charcoal combines a finer aggregate finish (joints from 3mm) with a bold charcoal tone — the ideal choice for charcoal or grey porcelain, granite setts, slate and darker natural stones where a defined, colour-matched joint is needed. It meets BS 7533 standards, achieves a compressive strength of 49.6N/mm², resists weed growth, and lasts up to 40 years. Supplied in 25kg showerproof bags, sets in 15 minutes, and can be applied in light rain.
For best results, use a neoprene squeegee for a clean, stain-free application. A temporary sealer such as Tile Rite Patio Prep Temporary Sealer is highly recommended for porous or darker stones to prevent grout haze and staining.
Ideal for: charcoal or grey porcelain (joints from 3mm), granite setts, slate, darker sandstone, Indian Stone, Yorkstone, clay pavers and concrete flags. Also suitable for darker limestone when used with a temporary pre-sealer.
Also available in Natural Grey. For pale natural stone and porcelain in a colour-matched tone, see Flowpoint Premium Smooth Limestone, Stone Grey and Yorkstone.
Coverage Guide (approximate)
- Porcelain (600×900, 5×20mm joints): 1 bag ≈ 30m²
- Natural Stone (mixed pack): 1 bag ≈ 12–20m²
- Granite Setts: 1 bag ≈ 1.5–2m²
Use our calculator below for a precise estimate based on your patio size and joint width.
Got a question about Flowpoint Smooth? See our Flowpoint FAQs, download the technical datasheet (PDF), or contact us. Alternatively, call 0330 122 1025 — we're always happy to help.
UltraScape Flowpoint Smooth Rapid Set External Paving Grout | Charcoal | 25kg
'Fine-Aggregate Flowable Grout in Charcoal — Joints from 3mm — Perfect for Porcelain, Granite Setts & Darker Natural Stone'
UltraScape Flowpoint Smooth Charcoal is one of the most versatile rapid-set paving grouts in the range — combining the finer aggregate of Flowpoint Smooth (joints from just 3mm) with the bold, deep tone of Charcoal. It's BS 7533 compliant, sets in 15 minutes at 20°C, lasts up to 40 years, and is particularly well suited to charcoal or grey porcelain, granite setts, slate and darker natural stones where a defined, colour-matched joint makes all the difference. It's a product our customers consistently come back to tell us they're delighted with.
BS 7533 compliant, sets in 15 minutes at 20°C, joints from 3–50mm wide and 20–200mm deep, open to vehicles in 4 hours, 49.6N/mm² compressive strength, supplied in 25kg showerproof bags — Flowpoint Smooth Charcoal is a professional-strength flowable paving grout equally at home on a domestic porcelain patio or a large-scale commercial carriageway scheme.
We're a small, family-run business — I'm Cleo, the owner, with over 25 years in the construction industry working with businesses including Tarmac and Instarmac. I work alongside a team of incredibly knowledgeable and caring individuals, and between us we've seen a lot of paving grouts come and go. Flowpoint Smooth Charcoal is a firm favourite for contractors working with porcelain and granite setts — the finer aggregate flows cleanly into tight joints, and the charcoal tone gives a crisp, contemporary finish.
If you're jointing charcoal or grey porcelain, granite setts, slate, darker sandstone or Indian Stone — and particularly if your joints are narrower than 5mm — Flowpoint Smooth Charcoal is the product we'd confidently recommend. With darker limestones, Flowpoint can cause oxidisation — however, the new generation of temporary pre-sealers such as Tile Rite Patio Prep Temporary Sealer prevent this, making Flowpoint a viable option even for darker stones when used correctly. If you're unsure, read our black limestone blog or give us a call.
UltraScape Flowpoint Smooth Charcoal is a flowable, rapid-setting, cement-based paving grout with a finer aggregate finish, ideal for filling joints from just 3mm between porcelain, granite setts, slate and darker natural stone. Simply mixed with water, it produces a flowable slurry that is poured across the paving, squeegeed into the joints, and cleaned down to reveal strong, durable, weed-free joints. Compared to traditional hand-pointing it is dramatically faster and far less labour-intensive.
What Do Industry Experts Say About Flowpoint?
We know that switching to a slurry jointing mortar can feel like a leap of faith. So we asked Gareth Wilson, one of the UK's most respected hard landscaping experts, for his honest view.
Gareth has 30 years in the landscaping trade, 30 Royal Horticultural Show (RHS) awards for show garden construction, and now works as an expert witness in hard landscaping:
GARETH WILSON — Hard Landscaping Expert & RHS Award Winner
"Some landscapers are stuck in their ways and they don't like change. Their attitude is, 'I've been doing this for 20 years… Why should I change now?' And some are quite rightly scared when they consider pouring Flowpoint onto their slabs — at the end of the day, you are pouring a cementitious slurry directly onto the pavers. It goes against everything that you've been taught. But Flowpoint has been developed so it doesn't stick to the paving."In addition to its British Standard rating and the strength of the product, it's also the speed at which you can install it. If you're going to be on your hands and knees with a trowel and a three-to-one mortar mix, it will take you about five times as long to install, compared with using Flowpoint. Flowpoint is just so easy and quick to install that it makes you money. It's a well-priced product and, in my view, a landscaper's friend. Ultimately, it means less time on the job and more profit in your pocket."
JORDAN CLAYTON
"Flowpoint is our go-to product when it comes to jointing all our paving. Like the rest of the materials, I love how it gives me confidence that the products will stand the test of time, allowing homeowners to enjoy their garden for years to come."
Owner of Next Level Landscapes Ltd. (Courtesy of Instarmac Group Plc)
Approved for Use on the London Underground & Overground
Flowpoint Smooth is approved for use on the London Underground and London Overground and is NBS Source registered for ease of specification — making it straightforward to specify on commercial and public realm projects where a smooth, void-free joint finish is required.
Common Flowpoint Myths — Busted
| Myth | The Truth |
|---|---|
| Myth #1: Flowpoint is new | Flowpoint was developed by Instarmac around 25 years ago and has been used on thousands of major projects worldwide, including in New Zealand, Norway, America and Dubai. Instarmac have consistently added to the range with Standard, Smooth, ECO with 20% recycled glass, Fine for porcelain and smooth stone. |
| Myth #2: Flowpoint requires specialist equipment | Not at all. The only additional equipment you really need is a 110v paddle mixer and a long-handled neoprene squeegee. Most other items — such as buckets, extension leads, floats, trowels and cleaning equipment — are standard paving tools. |
| Myth #3: Only experienced contractors can use Flowpoint | Flowpoint can seem daunting at first, but it's straightforward once you know how. A quick demonstration and some practice can give contractors the confidence to use it themselves. As with any new product, always follow the manufacturer's instructions and watch a demonstration before starting. |
| Myth #4: Flowpoint sticks like glue to pavers | Although Flowpoint is rapid-setting, it doesn't set instantly. Keep the area damp and plan around the weather, particularly in hot temperatures. In very warm conditions, it's best to work during cooler parts of the day. |
| Myth #5: Flowpoint causes cracking and low spots | Cracking and low spots can occur if Flowpoint is washed off too early, particularly in colder weather. Timing is key — use the thumb or "finger-touch" test to check that the joints are firm before washing. If the grout is still bleeding from the joint, it's too early. |
| Myth #6: Flowpoint works with every paving material | Flowpoint works with most common paving materials, including sandstone, Indian stone, granite setts, cobbles, clay pavers, limestone, slate and ceramics. However, it should not be used with black limestone without a temporary pre-sealer, as it can oxidise and cause staining. |
| Myth #7: Flowpoint causes efflorescence | When applied correctly, Flowpoint should not cause efflorescence. Problems are more likely when the mortar bed hasn't dried sufficiently, too much water is used in the mix, or the joints are directly pressure-washed too early. |
| Myth #8: Paving must be kept completely wet | The surface should be kept damp, not saturated. Avoid standing or pooled water and use a light spray to maintain moisture. Too much water can dilute the Flowpoint mix and contribute to cracking or mortar failure. |
| Myth #9: Slabs must sit for 28 days before grouting | Not necessarily. The key is ensuring the bedding mortar has properly cured and there is no visible dampness. Although the manufacturer recommends waiting 21–28 days before using cement-based grout, contractors may grout sooner where the bed is solid, set and sufficiently dry. Always follow the manufacturer's guidance to minimise the risk of efflorescence and other issues. |
Flowpoint Smooth Key Information
- Unit size: 25kg showerproof bag
- Colours: Charcoal & Natural Grey
- Set time: 15 minutes at 20°C
- Open to foot traffic: 1 hour
- Open to vehicular traffic: 4 hours
- Classification: BS 7533
- Compressive strength: 49.6N/mm²
- Finer aggregate finish — ideal for joints from 3mm
- Exceptional bond strength
- Shrinkage compensated
- Provides a seamless, void-free surface
- Approved for use on the London Underground and Overground
- NBS Source registered
- Joint width: 3–50mm | Depth: 20–200mm
- Lasts up to 40 years without re-grouting
- Works in light rain
- Shelf life: 8 months (unopened)
Suitable Paving Types
- Charcoal or grey porcelain (joints from 3mm)
- Granite setts
- Slate
- Darker sandstone and Indian Stone
- Yorkstone
- Clay pavers
- Concrete flags
- Limestone (including darker limestone when used with a temporary pre-sealer)
Flowpoint Smooth Charcoal vs Natural Grey — Which Do You Need?
| Flowpoint Smooth Charcoal | Flowpoint Smooth Natural Grey | |
|---|---|---|
| Best for | Charcoal/grey porcelain, granite setts, slate, darker stones | Pale porcelain, sandstone, limestone, Indian Stone, mixed packs |
| Joint width | 3–50mm | 3–50mm |
| Set time | 15 minutes at 20°C | 15 minutes at 20°C |
| Compressive strength | 49.6N/mm² | 49.6N/mm² |
| BS 7533 compliant | Yes | Yes |
Flowpoint Grades & Colours — Which One Do You Need?
| Grade | Colours Available | Joint Width | Joint Depth |
|---|---|---|---|
| Flowpoint Standard | Natural Grey & Charcoal | 5–50mm | 20–200mm |
| Flowpoint Premium Standard | Stone Grey, Limestone & Yorkstone | 5–50mm | 20–200mm |
| Flowpoint ECO | Natural Grey & Charcoal | 5–50mm | 20–200mm |
| Flowpoint Smooth | Natural Grey & Charcoal | 3–50mm | 20–200mm |
| Flowpoint Premium Smooth | Limestone, Stone Grey & Yorkstone | 3–50mm | 20–200mm |
| Flowpoint Fine | Natural Grey & Charcoal | 2–50mm | 20–200mm |
| Porcelpoint (for porcelain) | Stone Grey & Limestone | 2–50mm | 20–200mm |
Flowpoint Smooth Approximate Coverage Guide (per 25kg bag)
- Porcelain (600×900, 5×20mm joints): approx. 30m²
- Natural Stone Mixed Packs: approx. 12–20m²
- Granite Setts: approx. 1.5–2m²
For the most accurate calculation, use The Paving Experts' Flowpoint Calculator on the product page to estimate coverage for your exact paving size and joint width.
Frequently Asked Questions — UltraScape Flowpoint Smooth Charcoal
I'm Cleo, owner of The Paving Experts, with over 25 years in the construction industry working with businesses including Tarmac and Instarmac. I work alongside a small team of incredibly knowledgeable and caring individuals who share the same passion for getting it right. The FAQ answers below come from the questions we're asked every single day — so if yours isn't there, just give us a call.
1. What is UltraScape Flowpoint Smooth?
UltraScape Flowpoint Smooth is a rapid-set, flowable paving grout designed specifically for smooth paving stones and slabs. It produces a seamless, void-free joint that conforms to the requirements of BS 7533. Pre-mixed and supplied in 25kg showerproof bags, it requires only the addition of water on site — making it one of the fastest, most consistent ways to joint large areas of smooth or polished paving.
2. What is Flowpoint Smooth used for?
Flowpoint Smooth is used for jointing paving in a wide range of applications — from domestic patios and driveways to town centre pedestrian schemes, pathways and carriageways. It is suitable for natural stone, concrete flags and clay pavers, and is particularly well suited to smooth or polished surfaces where a seamless, void-free finish is required. It is ideal for large-scale projects where speed and consistency of application matter.
3. What is Flowpoint Smooth and how is it different from Flowpoint Standard?
Flowpoint Smooth is a rapid set flowable grout engineered for smooth paving stones and slabs where joints can be as narrow as 3mm — two millimetres tighter than Flowpoint Standard (5mm minimum). Its high fluid consistency produces a seamless, void-free joint that is particularly well suited to smooth or polished surfaces. The compressive strength, application method, water ratio and trafficking times are identical to Standard.
4. Why choose Charcoal over Natural Grey for Flowpoint Smooth?
Charcoal creates a bolder, more defined joint that works particularly well with charcoal or grey porcelain, granite setts, slate and darker natural stones. It gives a contemporary, high-contrast finish that frames the paving beautifully. Natural Grey is the more neutral option — if you're unsure which suits your stone, send us a photo and we'll advise.
5. What joint widths can Flowpoint Smooth be used for?
Flowpoint Smooth handles joints from 3mm to 50mm wide and 20mm to 200mm deep in a single application — narrower than Flowpoint Standard, which starts at 5mm. For joints narrower than 3mm, consider Flowpoint Fine (from 2mm) or Porcelpoint (from 2mm). Give us a call if you're unsure which grade is right for your project.
6. What is the set time for Flowpoint Smooth?
Flowpoint Smooth reaches initial set in 15 minutes at 20°C. Temperature is the key variable — colder conditions extend the set, warmer ones shorten it. Always use the thumb test before cleaning down — if the joint still feels soft, it's too early.
7. How long before you can walk on Flowpoint Smooth?
Flowpoint Smooth can accept light foot traffic after approximately 1 hour, depending on temperature. In colder conditions, allow a little longer before walking on the surface.
8. How long before vehicles can drive over Flowpoint Smooth?
Flowpoint Smooth can accept vehicular traffic after approximately 4 hours, depending on temperature. This makes it an excellent choice for driveways, pathways and carriageway schemes where downtime needs to be kept to a minimum.
9. Is UltraScape Flowpoint Smooth BS 7533 compliant?
Yes — UltraScape Flowpoint Smooth conforms to and exceeds the requirements of BS 7533. It is designed for rigid or bound, void-free paving joints and is NBS Source registered for ease of specification on commercial and public realm projects.
10. Can Flowpoint Smooth Charcoal be used on porcelain paving?
Yes — Flowpoint Smooth Charcoal is well suited to charcoal or grey porcelain paving, particularly where joints are 3mm or wider. Its high fluid consistency flows cleanly into tight joints without bridging or voids. For porcelain, we also strongly recommend a temporary pre-sealer such as Tile Rite Patio Prep to prevent grout haze on the polished surface.
11. Can Flowpoint Smooth Charcoal be used on natural stone paving?
Yes — Flowpoint Smooth Charcoal is suitable for granite setts, slate, darker sandstone, Indian Stone and Yorkstone. Always carry out a small trial on your specific stone first. For darker limestones such as black limestone, apply a temporary pre-sealer like Tile Rite Patio Prep to prevent oxidisation.
12. Can Flowpoint Smooth be used on concrete paving?
Yes — Flowpoint Smooth is suitable for concrete flags and is an excellent choice for any paving application requiring a rigid, bound, void-free joint. Its high fluid consistency means it fills joints in concrete paving quickly and consistently, with no need for hand-pointing.
13. Can Flowpoint Smooth be used on clay pavers?
Yes — Flowpoint Smooth is suitable for clay pavers. As with all stone types, we recommend a small trial area first, and for any absorbent surface, ensure the paving is thoroughly pre-soaked before application to prevent the grout being drawn in too quickly.
14. Is Flowpoint Smooth suitable for driveways and high-traffic areas?
Yes — Flowpoint Smooth is designed for applications including pathways, town centre pedestrian schemes and carriageways. With a compressive strength of 49.6N/mm² and vehicular trafficking possible after just 4 hours, it is well suited to driveways, commercial car parks and any surface that needs to return to use quickly.
15. Is Flowpoint Smooth suitable for large paving areas?
Yes — Flowpoint Smooth is specifically identified by Instarmac as ideal for large-scale projects. Its high fluid consistency allows large areas to be grouted efficiently — far faster than traditional hand-pointing. Working in manageable sections and keeping the surface misted is the key to a clean, consistent result across a large area.
16. How do you apply Flowpoint Smooth Charcoal?
Pre-soak the paving and remove all ponded water. Add 4.25 litres of clean water per 25kg bag and mix for 3–5 minutes until smooth and lump-free. Pour onto the paving and work into joints using a neoprene squeegee. Keep the surface misted throughout. Once initial set is reached, clean down with a brush and plenty of clean water. Mix only what you can place in approximately 4 minutes — never add more water or remix.
17. How much water do you add to a 25kg bag of Flowpoint Smooth?
Exactly 4.25 litres of clean water per bag. Mix for 3–5 minutes with a slow-speed drill and paddle mixer until smooth and pourable. Never add more water once mixing has started and never remix a batch that has begun to go off.
18. Is Flowpoint Smooth easy to mix?
Yes — Flowpoint Smooth is supplied as a fully pre-mixed dry-pack and only requires the addition of water on site. A slow-speed drill with a paddle mixer attachment is all you need. Mix for 3–5 minutes until smooth and lump-free. No specialist equipment required.
19. What colours does Flowpoint Smooth come in?
Flowpoint Smooth is available in Charcoal and Natural Grey. For a wider palette — Stone Grey, Limestone and Yorkstone — the Flowpoint Premium Smooth range offers the same performance in additional tones.
20. Can Flowpoint Smooth Charcoal be used with black limestone?
Flowpoint can cause oxidisation on some darker limestones such as black limestone — however, the new generation of temporary pre-sealers, such as Tile Rite Patio Prep Temporary Sealer, prevent this by creating a protective barrier between the stone and the grout. If you'd like advice on your specific stone, give us a call — we're happy to help.
21. Will Flowpoint Smooth Charcoal stain my paving?
Flowpoint Smooth is designed to be stain-free when applied correctly. Staining is not a product fault — it's typically caused by skipping a paving primer, not misting slabs during application, or over-watering the mix. Use a neoprene squeegee, keep slabs misted, and consider a temporary sealer such as Tile Rite Patio Prep for porous or textured stones.
22. Is Flowpoint Smooth permeable?
No — Flowpoint Smooth is a non-permeable cementitious grout. Once set, it does not allow water to pass through the joint. It must be used on a solid, non-permeable bed. If you need a permeable jointing solution, contact us and we'll point you in the right direction.
23. Can you use Flowpoint Smooth in the rain?
Yes — light rain is fine, but ensure the joints don't fill with rainwater before you begin. A damp day can actually be beneficial as it slows the set and gives you more working time. Do not apply during heavy rain or when frost is forecast within 24 hours.
24. Do I need to pre-seal my slabs before using Flowpoint Smooth?
If using a temporary pre-grout sealer (such as Tile Rite Patio Prep or Nexus ProJoint Pre-Grout): do not pre-soak the paving. The sealer acts as the protective barrier — water is not required until clean-down.
If not using a temporary sealer: thoroughly wet the paving with a hose spray before applying, then remove all standing or ponded water from the surface and joints — a leaf blower is ideal. The surface should be damp, not waterlogged.
25. What is the shelf life of Flowpoint Smooth?
8 months from the date of manufacture (printed on the bag, on the white strip on the side of the bag), for unopened, sealed bags stored in a cool, dry, frost-free area. Using the product after the declared storage period may increase the risk of an allergic reaction.
26. How much Flowpoint Smooth do I need?
Coverage varies depending on joint size and depth, paving stone size, surface absorption and wastage. Use the Flowpoint Calculator on this page for an accurate estimate, or call us and we'll work it out for you.
27. How long does Flowpoint Smooth last?
When applied correctly on a properly prepared bed, Flowpoint Smooth Charcoal can last up to 40 years without the need to re-grout.
28. How do I tell the Flowpoint grades apart on delivery?
The bag colour tells you the grade at a glance. Flowpoint Smooth bags are orange and blue. For reference across the full range: Standard is black and orange; ECO is orange and green; Fine comes in tubs rather than bags, with the lid colour indicating the colour variant. On all bags, the specific colour variant (Natural Grey or Charcoal) is printed on the white strip on the side of the bag.
Watch the video...
Please note: The videos below show Flowpoint Fine being applied. The mixing and application principles are exactly the same for Flowpoint Smooth — the only difference is the water ratio. Flowpoint Fine and Porcelpoint require 3.4 litres of clean water per 20kg bucket, whereas Flowpoint Standard, Smooth, ECO and Premium require 4.25 litres of water per 25kg bag.
Want to learn more about UltraScape Flowpoint?
Read our blog post 'What is Flowpoint', or for more in-depth questions see our Flowpoint FAQs.
Want to order a pallet quantity?
View our 56-bag full pallet or 40-bag part pallet — both include free standard delivery.
Need a paving primer & bedding mortar?
We recommend using the full UltraScape BS 7533 Mortar Paving System — a range of high-performance materials that meet and exceed the strict demands of BS 7533. Including rapid-strength fine bedding concrete EcoBed, priming slurry Pro-Prime, and flowable jointing grout Flowpoint.
If you'd like to know more about Flowpoint Smooth Charcoal, which grade is right for your project, or need help colour-matching — don't hesitate to get in touch or call us on 0330 122 1025. We're a small team but we know our products inside out, and we're always happy to help.
- Brand: Instarmac
- Product Type: Paving Grout
- SKU: TPE-ULTFLORABF7
- Weight: 25.0 kg / 55.12 lb
Delivery & Returns Info
Our delivery charges are calculated based on the size and weight of your order. When you add items to your basket, the delivery charges are displayed. Small orders are distributed via courier; larger orders via Pallet Network. Collection is available from our Tamworth depot by request (contact us first to arrange on 0330 122 1025).
Please note, there is a slight surcharge for areas that are outside of our locality, charges calculated at checkout.
| Weight and size | Next Working Day* Order before 1PM (excl. VAT) |
Standard 3-5 Working Day (excl. VAT) |
|---|---|---|
| 0-13KG (1 small bag/tub) |
£14.00 | £9.00 |
| 13.01-25KG (1 large bag/tub) |
£16.00 | £10.00 |
| 25.01-50KG (2 bags/tubs) |
£26.00 | £19.00 |
| 50.01-75KG (3 bags/tubs) |
£36.00 | £28.00 |
| 75.01-100KG (4-5 bags/tubs) |
£46.00 | £37.00 |
| 100.01-249KG (6-9 bags/tubs) |
£60.00 | £45.00 |
| 249.01-750KG (10 bags plus) |
£68.00 | £48.00 |
| 750.01KG plus (30 bags plus) |
£75.00 | £55.00 |
| Full Pallets (56 bags/52 tubs) |
£88.00 | Free of charge |
| Next Working Day delivery (Premium 1-2 Working Day Service) | +avg. £5-10 Extra. Click here for prices |
|---|---|
| Scotland Delivery Service (Deliveries into some parts of Scotland can take 8-10 working days) | Click here for prices |
| Local Delivery & Click & Collect: | Email: orders@thepavingexperts.co.uk |
Delivery Information
- Prices apply to mainland England and Wales. Scottish delivery slight surcharge.
- Orders are packed and dispatched Monday–Friday (excluding weekends & public holidays).
Next Working Day Delivery
- Order before 1PM → same-day dispatch.
- Order after 1PM or on weekends/bank holidays → next working day dispatch.
- You'll receive tracking updates via email/SMS if you provide your details.
Delivery Examples
- Mon before 1PM → Packed Mon, delivered Tue.
- Mon after 1PM → Packed Tues delivered Wed.
- Fri before 1PM → Packed Fri, delivered Mon.
- Fri after 1PM/weekend → Packed Mon, delivered Tues (or Wed after a bank holiday).
- Standard Service: 3–5 working days.
Notes
- Occasional delays due to manufacturing, supply, or courier issues may happen, but we'll keep you informed.
Returns, cancel up to 14 days from date of delivery. Product to be returned in the same condition & packaging. No returns for cementitious & perishable products. You are responsible for the cost of returning goods to The Paving Experts, 20% admin restock fee applies. Need further info, click here.
For further detailed delivery information click here →
For any advice; technical, product, stock or quantity needed, call our team on 0330 122 1025.
Please see our FAQs for more information.
UltraScape Flowpoint Smooth Rapid Set External Paving Grout | Charcoal | 25kg
'Fine-Aggregate Flowable Grout in Charcoal — Joints from 3mm — Perfect for Porcelain, Granite Setts & Darker Natural Stone'
UltraScape Flowpoint Smooth Charcoal is one of the most versatile rapid-set paving grouts in the range — combining the finer aggregate of Flowpoint Smooth (joints from just 3mm) with the bold, deep tone of Charcoal. It's BS 7533 compliant, sets in 15 minutes at 20°C, lasts up to 40 years, and is particularly well suited to charcoal or grey porcelain, granite setts, slate and darker natural stones where a defined, colour-matched joint makes all the difference. It's a product our customers consistently come back to tell us they're delighted with.
BS 7533 compliant, sets in 15 minutes at 20°C, joints from 3–50mm wide and 20–200mm deep, open to vehicles in 4 hours, 49.6N/mm² compressive strength, supplied in 25kg showerproof bags — Flowpoint Smooth Charcoal is a professional-strength flowable paving grout equally at home on a domestic porcelain patio or a large-scale commercial carriageway scheme.
We're a small, family-run business — I'm Cleo, the owner, with over 25 years in the construction industry working with businesses including Tarmac and Instarmac. I work alongside a team of incredibly knowledgeable and caring individuals, and between us we've seen a lot of paving grouts come and go. Flowpoint Smooth Charcoal is a firm favourite for contractors working with porcelain and granite setts — the finer aggregate flows cleanly into tight joints, and the charcoal tone gives a crisp, contemporary finish.
If you're jointing charcoal or grey porcelain, granite setts, slate, darker sandstone or Indian Stone — and particularly if your joints are narrower than 5mm — Flowpoint Smooth Charcoal is the product we'd confidently recommend. With darker limestones, Flowpoint can cause oxidisation — however, the new generation of temporary pre-sealers such as Tile Rite Patio Prep Temporary Sealer prevent this, making Flowpoint a viable option even for darker stones when used correctly. If you're unsure, read our black limestone blog or give us a call.
UltraScape Flowpoint Smooth Charcoal is a flowable, rapid-setting, cement-based paving grout with a finer aggregate finish, ideal for filling joints from just 3mm between porcelain, granite setts, slate and darker natural stone. Simply mixed with water, it produces a flowable slurry that is poured across the paving, squeegeed into the joints, and cleaned down to reveal strong, durable, weed-free joints. Compared to traditional hand-pointing it is dramatically faster and far less labour-intensive.
What Do Industry Experts Say About Flowpoint?
We know that switching to a slurry jointing mortar can feel like a leap of faith. So we asked Gareth Wilson, one of the UK's most respected hard landscaping experts, for his honest view.
Gareth has 30 years in the landscaping trade, 30 Royal Horticultural Show (RHS) awards for show garden construction, and now works as an expert witness in hard landscaping:
GARETH WILSON — Hard Landscaping Expert & RHS Award Winner
"Some landscapers are stuck in their ways and they don't like change. Their attitude is, 'I've been doing this for 20 years… Why should I change now?' And some are quite rightly scared when they consider pouring Flowpoint onto their slabs — at the end of the day, you are pouring a cementitious slurry directly onto the pavers. It goes against everything that you've been taught. But Flowpoint has been developed so it doesn't stick to the paving."In addition to its British Standard rating and the strength of the product, it's also the speed at which you can install it. If you're going to be on your hands and knees with a trowel and a three-to-one mortar mix, it will take you about five times as long to install, compared with using Flowpoint. Flowpoint is just so easy and quick to install that it makes you money. It's a well-priced product and, in my view, a landscaper's friend. Ultimately, it means less time on the job and more profit in your pocket."
JORDAN CLAYTON
"Flowpoint is our go-to product when it comes to jointing all our paving. Like the rest of the materials, I love how it gives me confidence that the products will stand the test of time, allowing homeowners to enjoy their garden for years to come."
Owner of Next Level Landscapes Ltd. (Courtesy of Instarmac Group Plc)
Approved for Use on the London Underground & Overground
Flowpoint Smooth is approved for use on the London Underground and London Overground and is NBS Source registered for ease of specification — making it straightforward to specify on commercial and public realm projects where a smooth, void-free joint finish is required.
Common Flowpoint Myths — Busted
| Myth | The Truth |
|---|---|
| Myth #1: Flowpoint is new | Flowpoint was developed by Instarmac around 25 years ago and has been used on thousands of major projects worldwide, including in New Zealand, Norway, America and Dubai. Instarmac have consistently added to the range with Standard, Smooth, ECO with 20% recycled glass, Fine for porcelain and smooth stone. |
| Myth #2: Flowpoint requires specialist equipment | Not at all. The only additional equipment you really need is a 110v paddle mixer and a long-handled neoprene squeegee. Most other items — such as buckets, extension leads, floats, trowels and cleaning equipment — are standard paving tools. |
| Myth #3: Only experienced contractors can use Flowpoint | Flowpoint can seem daunting at first, but it's straightforward once you know how. A quick demonstration and some practice can give contractors the confidence to use it themselves. As with any new product, always follow the manufacturer's instructions and watch a demonstration before starting. |
| Myth #4: Flowpoint sticks like glue to pavers | Although Flowpoint is rapid-setting, it doesn't set instantly. Keep the area damp and plan around the weather, particularly in hot temperatures. In very warm conditions, it's best to work during cooler parts of the day. |
| Myth #5: Flowpoint causes cracking and low spots | Cracking and low spots can occur if Flowpoint is washed off too early, particularly in colder weather. Timing is key — use the thumb or "finger-touch" test to check that the joints are firm before washing. If the grout is still bleeding from the joint, it's too early. |
| Myth #6: Flowpoint works with every paving material | Flowpoint works with most common paving materials, including sandstone, Indian stone, granite setts, cobbles, clay pavers, limestone, slate and ceramics. However, it should not be used with black limestone without a temporary pre-sealer, as it can oxidise and cause staining. |
| Myth #7: Flowpoint causes efflorescence | When applied correctly, Flowpoint should not cause efflorescence. Problems are more likely when the mortar bed hasn't dried sufficiently, too much water is used in the mix, or the joints are directly pressure-washed too early. |
| Myth #8: Paving must be kept completely wet | The surface should be kept damp, not saturated. Avoid standing or pooled water and use a light spray to maintain moisture. Too much water can dilute the Flowpoint mix and contribute to cracking or mortar failure. |
| Myth #9: Slabs must sit for 28 days before grouting | Not necessarily. The key is ensuring the bedding mortar has properly cured and there is no visible dampness. Although the manufacturer recommends waiting 21–28 days before using cement-based grout, contractors may grout sooner where the bed is solid, set and sufficiently dry. Always follow the manufacturer's guidance to minimise the risk of efflorescence and other issues. |
Flowpoint Smooth Key Information
- Unit size: 25kg showerproof bag
- Colours: Charcoal & Natural Grey
- Set time: 15 minutes at 20°C
- Open to foot traffic: 1 hour
- Open to vehicular traffic: 4 hours
- Classification: BS 7533
- Compressive strength: 49.6N/mm²
- Finer aggregate finish — ideal for joints from 3mm
- Exceptional bond strength
- Shrinkage compensated
- Provides a seamless, void-free surface
- Approved for use on the London Underground and Overground
- NBS Source registered
- Joint width: 3–50mm | Depth: 20–200mm
- Lasts up to 40 years without re-grouting
- Works in light rain
- Shelf life: 8 months (unopened)
Suitable Paving Types
- Charcoal or grey porcelain (joints from 3mm)
- Granite setts
- Slate
- Darker sandstone and Indian Stone
- Yorkstone
- Clay pavers
- Concrete flags
- Limestone (including darker limestone when used with a temporary pre-sealer)
Flowpoint Smooth Charcoal vs Natural Grey — Which Do You Need?
| Flowpoint Smooth Charcoal | Flowpoint Smooth Natural Grey | |
|---|---|---|
| Best for | Charcoal/grey porcelain, granite setts, slate, darker stones | Pale porcelain, sandstone, limestone, Indian Stone, mixed packs |
| Joint width | 3–50mm | 3–50mm |
| Set time | 15 minutes at 20°C | 15 minutes at 20°C |
| Compressive strength | 49.6N/mm² | 49.6N/mm² |
| BS 7533 compliant | Yes | Yes |
Flowpoint Grades & Colours — Which One Do You Need?
| Grade | Colours Available | Joint Width | Joint Depth |
|---|---|---|---|
| Flowpoint Standard | Natural Grey & Charcoal | 5–50mm | 20–200mm |
| Flowpoint Premium Standard | Stone Grey, Limestone & Yorkstone | 5–50mm | 20–200mm |
| Flowpoint ECO | Natural Grey & Charcoal | 5–50mm | 20–200mm |
| Flowpoint Smooth | Natural Grey & Charcoal | 3–50mm | 20–200mm |
| Flowpoint Premium Smooth | Limestone, Stone Grey & Yorkstone | 3–50mm | 20–200mm |
| Flowpoint Fine | Natural Grey & Charcoal | 2–50mm | 20–200mm |
| Porcelpoint (for porcelain) | Stone Grey & Limestone | 2–50mm | 20–200mm |
Flowpoint Smooth Approximate Coverage Guide (per 25kg bag)
- Porcelain (600×900, 5×20mm joints): approx. 30m²
- Natural Stone Mixed Packs: approx. 12–20m²
- Granite Setts: approx. 1.5–2m²
For the most accurate calculation, use The Paving Experts' Flowpoint Calculator on the product page to estimate coverage for your exact paving size and joint width.
Frequently Asked Questions — UltraScape Flowpoint Smooth Charcoal
I'm Cleo, owner of The Paving Experts, with over 25 years in the construction industry working with businesses including Tarmac and Instarmac. I work alongside a small team of incredibly knowledgeable and caring individuals who share the same passion for getting it right. The FAQ answers below come from the questions we're asked every single day — so if yours isn't there, just give us a call.
1. What is UltraScape Flowpoint Smooth?
UltraScape Flowpoint Smooth is a rapid-set, flowable paving grout designed specifically for smooth paving stones and slabs. It produces a seamless, void-free joint that conforms to the requirements of BS 7533. Pre-mixed and supplied in 25kg showerproof bags, it requires only the addition of water on site — making it one of the fastest, most consistent ways to joint large areas of smooth or polished paving.
2. What is Flowpoint Smooth used for?
Flowpoint Smooth is used for jointing paving in a wide range of applications — from domestic patios and driveways to town centre pedestrian schemes, pathways and carriageways. It is suitable for natural stone, concrete flags and clay pavers, and is particularly well suited to smooth or polished surfaces where a seamless, void-free finish is required. It is ideal for large-scale projects where speed and consistency of application matter.
3. What is Flowpoint Smooth and how is it different from Flowpoint Standard?
Flowpoint Smooth is a rapid set flowable grout engineered for smooth paving stones and slabs where joints can be as narrow as 3mm — two millimetres tighter than Flowpoint Standard (5mm minimum). Its high fluid consistency produces a seamless, void-free joint that is particularly well suited to smooth or polished surfaces. The compressive strength, application method, water ratio and trafficking times are identical to Standard.
4. Why choose Charcoal over Natural Grey for Flowpoint Smooth?
Charcoal creates a bolder, more defined joint that works particularly well with charcoal or grey porcelain, granite setts, slate and darker natural stones. It gives a contemporary, high-contrast finish that frames the paving beautifully. Natural Grey is the more neutral option — if you're unsure which suits your stone, send us a photo and we'll advise.
5. What joint widths can Flowpoint Smooth be used for?
Flowpoint Smooth handles joints from 3mm to 50mm wide and 20mm to 200mm deep in a single application — narrower than Flowpoint Standard, which starts at 5mm. For joints narrower than 3mm, consider Flowpoint Fine (from 2mm) or Porcelpoint (from 2mm). Give us a call if you're unsure which grade is right for your project.
6. What is the set time for Flowpoint Smooth?
Flowpoint Smooth reaches initial set in 15 minutes at 20°C. Temperature is the key variable — colder conditions extend the set, warmer ones shorten it. Always use the thumb test before cleaning down — if the joint still feels soft, it's too early.
7. How long before you can walk on Flowpoint Smooth?
Flowpoint Smooth can accept light foot traffic after approximately 1 hour, depending on temperature. In colder conditions, allow a little longer before walking on the surface.
8. How long before vehicles can drive over Flowpoint Smooth?
Flowpoint Smooth can accept vehicular traffic after approximately 4 hours, depending on temperature. This makes it an excellent choice for driveways, pathways and carriageway schemes where downtime needs to be kept to a minimum.
9. Is UltraScape Flowpoint Smooth BS 7533 compliant?
Yes — UltraScape Flowpoint Smooth conforms to and exceeds the requirements of BS 7533. It is designed for rigid or bound, void-free paving joints and is NBS Source registered for ease of specification on commercial and public realm projects.
10. Can Flowpoint Smooth Charcoal be used on porcelain paving?
Yes — Flowpoint Smooth Charcoal is well suited to charcoal or grey porcelain paving, particularly where joints are 3mm or wider. Its high fluid consistency flows cleanly into tight joints without bridging or voids. For porcelain, we also strongly recommend a temporary pre-sealer such as Tile Rite Patio Prep to prevent grout haze on the polished surface.
11. Can Flowpoint Smooth Charcoal be used on natural stone paving?
Yes — Flowpoint Smooth Charcoal is suitable for granite setts, slate, darker sandstone, Indian Stone and Yorkstone. Always carry out a small trial on your specific stone first. For darker limestones such as black limestone, apply a temporary pre-sealer like Tile Rite Patio Prep to prevent oxidisation.
12. Can Flowpoint Smooth be used on concrete paving?
Yes — Flowpoint Smooth is suitable for concrete flags and is an excellent choice for any paving application requiring a rigid, bound, void-free joint. Its high fluid consistency means it fills joints in concrete paving quickly and consistently, with no need for hand-pointing.
13. Can Flowpoint Smooth be used on clay pavers?
Yes — Flowpoint Smooth is suitable for clay pavers. As with all stone types, we recommend a small trial area first, and for any absorbent surface, ensure the paving is thoroughly pre-soaked before application to prevent the grout being drawn in too quickly.
14. Is Flowpoint Smooth suitable for driveways and high-traffic areas?
Yes — Flowpoint Smooth is designed for applications including pathways, town centre pedestrian schemes and carriageways. With a compressive strength of 49.6N/mm² and vehicular trafficking possible after just 4 hours, it is well suited to driveways, commercial car parks and any surface that needs to return to use quickly.
15. Is Flowpoint Smooth suitable for large paving areas?
Yes — Flowpoint Smooth is specifically identified by Instarmac as ideal for large-scale projects. Its high fluid consistency allows large areas to be grouted efficiently — far faster than traditional hand-pointing. Working in manageable sections and keeping the surface misted is the key to a clean, consistent result across a large area.
16. How do you apply Flowpoint Smooth Charcoal?
Pre-soak the paving and remove all ponded water. Add 4.25 litres of clean water per 25kg bag and mix for 3–5 minutes until smooth and lump-free. Pour onto the paving and work into joints using a neoprene squeegee. Keep the surface misted throughout. Once initial set is reached, clean down with a brush and plenty of clean water. Mix only what you can place in approximately 4 minutes — never add more water or remix.
17. How much water do you add to a 25kg bag of Flowpoint Smooth?
Exactly 4.25 litres of clean water per bag. Mix for 3–5 minutes with a slow-speed drill and paddle mixer until smooth and pourable. Never add more water once mixing has started and never remix a batch that has begun to go off.
18. Is Flowpoint Smooth easy to mix?
Yes — Flowpoint Smooth is supplied as a fully pre-mixed dry-pack and only requires the addition of water on site. A slow-speed drill with a paddle mixer attachment is all you need. Mix for 3–5 minutes until smooth and lump-free. No specialist equipment required.
19. What colours does Flowpoint Smooth come in?
Flowpoint Smooth is available in Charcoal and Natural Grey. For a wider palette — Stone Grey, Limestone and Yorkstone — the Flowpoint Premium Smooth range offers the same performance in additional tones.
20. Can Flowpoint Smooth Charcoal be used with black limestone?
Flowpoint can cause oxidisation on some darker limestones such as black limestone — however, the new generation of temporary pre-sealers, such as Tile Rite Patio Prep Temporary Sealer, prevent this by creating a protective barrier between the stone and the grout. If you'd like advice on your specific stone, give us a call — we're happy to help.
21. Will Flowpoint Smooth Charcoal stain my paving?
Flowpoint Smooth is designed to be stain-free when applied correctly. Staining is not a product fault — it's typically caused by skipping a paving primer, not misting slabs during application, or over-watering the mix. Use a neoprene squeegee, keep slabs misted, and consider a temporary sealer such as Tile Rite Patio Prep for porous or textured stones.
22. Is Flowpoint Smooth permeable?
No — Flowpoint Smooth is a non-permeable cementitious grout. Once set, it does not allow water to pass through the joint. It must be used on a solid, non-permeable bed. If you need a permeable jointing solution, contact us and we'll point you in the right direction.
23. Can you use Flowpoint Smooth in the rain?
Yes — light rain is fine, but ensure the joints don't fill with rainwater before you begin. A damp day can actually be beneficial as it slows the set and gives you more working time. Do not apply during heavy rain or when frost is forecast within 24 hours.
24. Do I need to pre-seal my slabs before using Flowpoint Smooth?
If using a temporary pre-grout sealer (such as Tile Rite Patio Prep or Nexus ProJoint Pre-Grout): do not pre-soak the paving. The sealer acts as the protective barrier — water is not required until clean-down.
If not using a temporary sealer: thoroughly wet the paving with a hose spray before applying, then remove all standing or ponded water from the surface and joints — a leaf blower is ideal. The surface should be damp, not waterlogged.
25. What is the shelf life of Flowpoint Smooth?
8 months from the date of manufacture (printed on the bag, on the white strip on the side of the bag), for unopened, sealed bags stored in a cool, dry, frost-free area. Using the product after the declared storage period may increase the risk of an allergic reaction.
26. How much Flowpoint Smooth do I need?
Coverage varies depending on joint size and depth, paving stone size, surface absorption and wastage. Use the Flowpoint Calculator on this page for an accurate estimate, or call us and we'll work it out for you.
27. How long does Flowpoint Smooth last?
When applied correctly on a properly prepared bed, Flowpoint Smooth Charcoal can last up to 40 years without the need to re-grout.
28. How do I tell the Flowpoint grades apart on delivery?
The bag colour tells you the grade at a glance. Flowpoint Smooth bags are orange and blue. For reference across the full range: Standard is black and orange; ECO is orange and green; Fine comes in tubs rather than bags, with the lid colour indicating the colour variant. On all bags, the specific colour variant (Natural Grey or Charcoal) is printed on the white strip on the side of the bag.
Watch the video...
Please note: The videos below show Flowpoint Fine being applied. The mixing and application principles are exactly the same for Flowpoint Smooth — the only difference is the water ratio. Flowpoint Fine and Porcelpoint require 3.4 litres of clean water per 20kg bucket, whereas Flowpoint Standard, Smooth, ECO and Premium require 4.25 litres of water per 25kg bag.
Want to learn more about UltraScape Flowpoint?
Read our blog post 'What is Flowpoint', or for more in-depth questions see our Flowpoint FAQs.
Want to order a pallet quantity?
View our 56-bag full pallet or 40-bag part pallet — both include free standard delivery.
Need a paving primer & bedding mortar?
We recommend using the full UltraScape BS 7533 Mortar Paving System — a range of high-performance materials that meet and exceed the strict demands of BS 7533. Including rapid-strength fine bedding concrete EcoBed, priming slurry Pro-Prime, and flowable jointing grout Flowpoint.
If you'd like to know more about Flowpoint Smooth Charcoal, which grade is right for your project, or need help colour-matching — don't hesitate to get in touch or call us on 0330 122 1025. We're a small team but we know our products inside out, and we're always happy to help.
Flowpoint Smooth Charcoal — Full Technical Information
Product Overview
UltraScape Flowpoint Smooth Charcoal is a rapid-setting, flowable, cement-based paving grout with a finer aggregate finish for external use. Its finer particle size allows it to fill joints from just 3mm — making it the preferred choice over Flowpoint Standard for porcelain paving, smooth natural stone, and any application requiring a tighter joint. It conforms to BS 7533 and delivers the same proven performance as the wider Flowpoint range, in a bold charcoal tone suited to darker stones and contemporary paving schemes. Approved for use on the London Underground and Overground, and NBS Source registered.
Performance Data
| Property | Value |
|---|---|
| Classification | BS 7533 |
| Compressive strength | 49.6N/mm² |
| Bond strength | Exceptional |
| Shrinkage | Shrinkage compensated |
| Initial set | 15 minutes at 20°C |
| Open to foot traffic | 1 hour |
| Open to vehicular traffic | 4 hours |
| Expected service life | Up to 40 years |
| Permeability | Non-permeable (impermeable bed required) |
| Weather resistance | Can be applied in light rain |
| Frost resistance | Do not apply below 3°C or if frost expected within 24 hours |
Application Data
| Property | Value |
|---|---|
| Water requirement | 4.25 litres per 25kg bag |
| Mixing time | 3–5 minutes |
| Working time after mixing | Approx. 4 minutes — mix one bag at a time |
| Joint width | 3–50mm |
| Joint depth | 20–200mm (single application) |
| Supply format | 25kg showerproof bags (pre-mixed dry-pack — just add water) |
| Colours available | Charcoal & Natural Grey |
Coverage Guide (approximate, per 25kg bag)
| Paving Type | Approximate Coverage |
|---|---|
| Porcelain Paving (600×900, 5×20mm joints) | approx. 30m² |
| Natural Stone (mixed pack) | 12–20m² |
| Granite Setts | 1.5–2m² |
Coverage varies depending on joint width, depth, stone size, surface absorption and wastage. Use the Flowpoint Calculator on this page for an accurate estimate.
Suitable Substrates
- Charcoal or grey porcelain (joints from 3mm)
- Granite setts
- Slate
- Darker sandstone and Indian Stone
- Yorkstone
- Clay pavers
- Concrete flags
- Limestone (including darker limestone when used with a temporary pre-sealer)
Note: Flowpoint Smooth is not recommended for use on some darker limestones (e.g. black limestone) without a temporary pre-sealer, as it may cause slight oxidisation. Contact us for advice on your specific stone.
Approvals & Certifications
- Conforms to BS 7533
- Approved for use on the London Underground and London Overground
- NBS Source registered
- Part of the Flowpoint range — in use for over 25 years across public realm, commercial and domestic projects worldwide
Storage & Shelf Life
- Shelf life: 8 months from date of manufacture (printed on the white strip on the side of the bag)
- Store in a cool, dry, frost-free area in unopened, sealed bags, clear of the ground
- Using after the declared storage period may increase the risk of an allergic reaction
Health & Safety
- Contains cement — wear appropriate PPE including gloves and eye protection
- Wet cement can cause serious skin burns — avoid prolonged skin contact
- Wash hands and exposed skin thoroughly after use
- Keep out of reach of children
- Full Safety Data Sheet (SDS) available on request or from the UltraScape website
For the full technical datasheet, download the PDF here. For project-specific advice, get in touch or call us on 0330 122 1025.
How to Mix & Apply UltraScape Flowpoint Smooth Paving Grout
Step 1 — Preparation
There are two approaches depending on whether you are using a temporary pre-grout sealer or not:
Without a temporary pre-sealer (standard method):
- Ensure joints are clean and free from debris, dust and loose material.
- Thoroughly pre-soak the paving surface and joints with water — the paving must be properly wet before you begin.
- Then remove all standing or ponded water from the surface and from within the joints — a leaf blower is ideal for this. The paving should be damp, not waterlogged. This is the key step: the paving needs to be wet enough to prevent the grout drying out too quickly, but any excess standing water will over-dilute the mix and weaken the joint.
- Keep the surface moist throughout application by misting with a soft spray of water as you work — do not allow it to dry out.
With a temporary pre-grout sealer (e.g. Tile Rite Patio Prep or Nexus ProJoint Pre-Grout):
- Apply the temporary sealer to the paving in advance and allow it to dry as per the product instructions.
- Do not pre-soak the paving with water. The temporary sealer acts as the protective barrier at this stage — water is not required until clean-down.
- Remove any standing water from the joints using a leaf blower before grouting begins.
- Always carry out a small trial area first to ensure compatibility with your stone type.
Step 2 — Mixing
- Add 4.25 litres of clean water per 25kg bag into a clean bucket or mixing vessel.
- Gradually add the Flowpoint Smooth powder to the water (not the other way around) and mix for 3–5 minutes until a smooth, lump-free, pourable consistency is achieved. Use a slow-speed drill and paddle mixer for best results.
- Only mix what you can apply in approximately 4 minutes — do not store liquid mortar.
- Never remix or add extra water once mixed. Doing so will weaken the final joint and may cause staining.
Step 3 — Application
- Pour the mixed grout directly onto the paving surface.
- Using a neoprene squeegee, carefully force the mortar into the joints, working it across the surface repeatedly. The finer aggregate of Flowpoint Smooth flows particularly well into narrow joints — work methodically to ensure all joints are fully filled. Top up any joints where the mortar has slumped after initial placement.
- Use the squeegee to remove as much excess mortar as possible from the surface as you go.
- If not using a temporary pre-sealer, keep the surface constantly moist using a soft spray of water throughout application. If using a pre-sealer, water is not required until clean-down.
- Once the jointing mortar has reached its initial set and hardened sufficiently, clean the paving surface thoroughly using a brush and copious amounts of clean water. No mortar must be allowed to remain on the surface of the paving.
- Wash all tools frequently during application.
Step 4 — Trafficking
- Foot traffic: after 1 hour (at 20°C)
- Vehicular traffic: after 4 hours (at 20°C)
- Cool temperatures retard set; warm temperatures accelerate it. Avoid applying in direct sunlight or during frost.
Technical Specification (Mixing Tab Summary)
| Property | Value |
|---|---|
| Water requirement | 4.25 litres per 25kg bag |
| Mixing time | 3–5 minutes |
| Working time after mixing | Approx. 4 minutes |
| Initial set | 15 minutes at 20°C |
| Open to foot traffic | 1 hour |
| Open to vehicular traffic | 4 hours |
| Joint width | 3–50mm |
| Joint depth | 20–200mm (single application) |
Important Precautions
- Wear appropriate PPE — avoid skin and eye contact. Wet cement can cause serious burns to the skin.
- Never remix or add extra water to the mix once it has been prepared.
- If you are not using one of UltraScape's pre-bagged bedding mortars, take care when selecting aggregates or sands for your site-batched bedding mortar. Some bedding mortars can leach pigment into the Flowpoint, causing variation in joint colour. If in doubt, give us a call — we're happy to advise.
- Do not apply in temperatures below 3°C or if frost is expected within 24 hours.
- Do not apply in direct sunlight — the product will set rapidly and may be difficult to clean down.
- Store in a cool, dry, frost-free area. Shelf life: 8 months from date of manufacture (printed on the white strip on the side of the bag).
Delivery & Returns Info
Our delivery charges are calculated based on the size and weight of your order. When you add items to your basket, the delivery charges are displayed. Small orders are distributed via courier; larger orders via Pallet Network. Collection is available from our Tamworth depot by request (contact us first to arrange on 0330 122 1025).
Please note, there is a slight surcharge for areas that are outside of our locality, charges calculated at checkout.
| Weight and size | Next Working Day* Order before 1PM (excl. VAT) |
Standard 3-5 Working Day (excl. VAT) |
|---|---|---|
| 0-13KG (1 small bag/tub) |
£14.00 | £9.00 |
| 13.01-25KG (1 large bag/tub) |
£16.00 | £10.00 |
| 25.01-50KG (2 bags/tubs) |
£26.00 | £19.00 |
| 50.01-75KG (3 bags/tubs) |
£36.00 | £28.00 |
| 75.01-100KG (4-5 bags/tubs) |
£46.00 | £37.00 |
| 100.01-249KG (6-9 bags/tubs) |
£60.00 | £45.00 |
| 249.01-750KG (10 bags plus) |
£68.00 | £48.00 |
| 750.01KG plus (30 bags plus) |
£75.00 | £55.00 |
| Full Pallets (56 bags/52 tubs) |
£88.00 | Free of charge |
| Next Working Day delivery (Premium 1-2 Working Day Service) | +avg. £5-10 Extra. Click here for prices |
|---|---|
| Scotland Delivery Service (Deliveries into some parts of Scotland can take 8-10 working days) | Click here for prices |
| Local Delivery & Click & Collect: | Email: orders@thepavingexperts.co.uk |
Delivery Information
- Prices apply to mainland England and Wales. Scottish delivery slight surcharge.
- Orders are packed and dispatched Monday–Friday (excluding weekends & public holidays).
Next Working Day Delivery
- Order before 1PM → same-day dispatch.
- Order after 1PM or on weekends/bank holidays → next working day dispatch.
- You'll receive tracking updates via email/SMS if you provide your details.
Delivery Examples
- Mon before 1PM → Packed Mon, delivered Tue.
- Mon after 1PM → Packed Tues delivered Wed.
- Fri before 1PM → Packed Fri, delivered Mon.
- Fri after 1PM/weekend → Packed Mon, delivered Tues (or Wed after a bank holiday).
- Standard Service: 3–5 working days.
Notes
- Occasional delays due to manufacturing, supply, or courier issues may happen, but we'll keep you informed.
Returns, cancel up to 14 days from date of delivery. Product to be returned in the same condition & packaging. No returns for cementitious & perishable products. You are responsible for the cost of returning goods to The Paving Experts, 20% admin restock fee applies. Need further info, click here.
For further detailed delivery information click here →
UltraScape Flowpoint Smooth Rapid Set External Paving Grout | Charcoal | 25kg
'Fine-Aggregate Flowable Grout in Charcoal — Joints from 3mm — Perfect for Porcelain, Granite Setts & Darker Natural Stone'
UltraScape Flowpoint Smooth Charcoal is one of the most versatile rapid-set paving grouts in the range — combining the finer aggregate of Flowpoint Smooth (joints from just 3mm) with the bold, deep tone of Charcoal. It's BS 7533 compliant, sets in 15 minutes at 20°C, lasts up to 40 years, and is particularly well suited to charcoal or grey porcelain, granite setts, slate and darker natural stones where a defined, colour-matched joint makes all the difference. It's a product our customers consistently come back to tell us they're delighted with.
BS 7533 compliant, sets in 15 minutes at 20°C, joints from 3–50mm wide and 20–200mm deep, open to vehicles in 4 hours, 49.6N/mm² compressive strength, supplied in 25kg showerproof bags — Flowpoint Smooth Charcoal is a professional-strength flowable paving grout equally at home on a domestic porcelain patio or a large-scale commercial carriageway scheme.
We're a small, family-run business — I'm Cleo, the owner, with over 25 years in the construction industry working with businesses including Tarmac and Instarmac. I work alongside a team of incredibly knowledgeable and caring individuals, and between us we've seen a lot of paving grouts come and go. Flowpoint Smooth Charcoal is a firm favourite for contractors working with porcelain and granite setts — the finer aggregate flows cleanly into tight joints, and the charcoal tone gives a crisp, contemporary finish.
If you're jointing charcoal or grey porcelain, granite setts, slate, darker sandstone or Indian Stone — and particularly if your joints are narrower than 5mm — Flowpoint Smooth Charcoal is the product we'd confidently recommend. With darker limestones, Flowpoint can cause oxidisation — however, the new generation of temporary pre-sealers such as Tile Rite Patio Prep Temporary Sealer prevent this, making Flowpoint a viable option even for darker stones when used correctly. If you're unsure, read our black limestone blog or give us a call.
UltraScape Flowpoint Smooth Charcoal is a flowable, rapid-setting, cement-based paving grout with a finer aggregate finish, ideal for filling joints from just 3mm between porcelain, granite setts, slate and darker natural stone. Simply mixed with water, it produces a flowable slurry that is poured across the paving, squeegeed into the joints, and cleaned down to reveal strong, durable, weed-free joints. Compared to traditional hand-pointing it is dramatically faster and far less labour-intensive.
What Do Industry Experts Say About Flowpoint?
We know that switching to a slurry jointing mortar can feel like a leap of faith. So we asked Gareth Wilson, one of the UK's most respected hard landscaping experts, for his honest view.
Gareth has 30 years in the landscaping trade, 30 Royal Horticultural Show (RHS) awards for show garden construction, and now works as an expert witness in hard landscaping:
GARETH WILSON — Hard Landscaping Expert & RHS Award Winner
"Some landscapers are stuck in their ways and they don't like change. Their attitude is, 'I've been doing this for 20 years… Why should I change now?' And some are quite rightly scared when they consider pouring Flowpoint onto their slabs — at the end of the day, you are pouring a cementitious slurry directly onto the pavers. It goes against everything that you've been taught. But Flowpoint has been developed so it doesn't stick to the paving."In addition to its British Standard rating and the strength of the product, it's also the speed at which you can install it. If you're going to be on your hands and knees with a trowel and a three-to-one mortar mix, it will take you about five times as long to install, compared with using Flowpoint. Flowpoint is just so easy and quick to install that it makes you money. It's a well-priced product and, in my view, a landscaper's friend. Ultimately, it means less time on the job and more profit in your pocket."
JORDAN CLAYTON
"Flowpoint is our go-to product when it comes to jointing all our paving. Like the rest of the materials, I love how it gives me confidence that the products will stand the test of time, allowing homeowners to enjoy their garden for years to come."
Owner of Next Level Landscapes Ltd. (Courtesy of Instarmac Group Plc)
Approved for Use on the London Underground & Overground
Flowpoint Smooth is approved for use on the London Underground and London Overground and is NBS Source registered for ease of specification — making it straightforward to specify on commercial and public realm projects where a smooth, void-free joint finish is required.
Common Flowpoint Myths — Busted
| Myth | The Truth |
|---|---|
| Myth #1: Flowpoint is new | Flowpoint was developed by Instarmac around 25 years ago and has been used on thousands of major projects worldwide, including in New Zealand, Norway, America and Dubai. Instarmac have consistently added to the range with Standard, Smooth, ECO with 20% recycled glass, Fine for porcelain and smooth stone. |
| Myth #2: Flowpoint requires specialist equipment | Not at all. The only additional equipment you really need is a 110v paddle mixer and a long-handled neoprene squeegee. Most other items — such as buckets, extension leads, floats, trowels and cleaning equipment — are standard paving tools. |
| Myth #3: Only experienced contractors can use Flowpoint | Flowpoint can seem daunting at first, but it's straightforward once you know how. A quick demonstration and some practice can give contractors the confidence to use it themselves. As with any new product, always follow the manufacturer's instructions and watch a demonstration before starting. |
| Myth #4: Flowpoint sticks like glue to pavers | Although Flowpoint is rapid-setting, it doesn't set instantly. Keep the area damp and plan around the weather, particularly in hot temperatures. In very warm conditions, it's best to work during cooler parts of the day. |
| Myth #5: Flowpoint causes cracking and low spots | Cracking and low spots can occur if Flowpoint is washed off too early, particularly in colder weather. Timing is key — use the thumb or "finger-touch" test to check that the joints are firm before washing. If the grout is still bleeding from the joint, it's too early. |
| Myth #6: Flowpoint works with every paving material | Flowpoint works with most common paving materials, including sandstone, Indian stone, granite setts, cobbles, clay pavers, limestone, slate and ceramics. However, it should not be used with black limestone without a temporary pre-sealer, as it can oxidise and cause staining. |
| Myth #7: Flowpoint causes efflorescence | When applied correctly, Flowpoint should not cause efflorescence. Problems are more likely when the mortar bed hasn't dried sufficiently, too much water is used in the mix, or the joints are directly pressure-washed too early. |
| Myth #8: Paving must be kept completely wet | The surface should be kept damp, not saturated. Avoid standing or pooled water and use a light spray to maintain moisture. Too much water can dilute the Flowpoint mix and contribute to cracking or mortar failure. |
| Myth #9: Slabs must sit for 28 days before grouting | Not necessarily. The key is ensuring the bedding mortar has properly cured and there is no visible dampness. Although the manufacturer recommends waiting 21–28 days before using cement-based grout, contractors may grout sooner where the bed is solid, set and sufficiently dry. Always follow the manufacturer's guidance to minimise the risk of efflorescence and other issues. |
Flowpoint Smooth Key Information
- Unit size: 25kg showerproof bag
- Colours: Charcoal & Natural Grey
- Set time: 15 minutes at 20°C
- Open to foot traffic: 1 hour
- Open to vehicular traffic: 4 hours
- Classification: BS 7533
- Compressive strength: 49.6N/mm²
- Finer aggregate finish — ideal for joints from 3mm
- Exceptional bond strength
- Shrinkage compensated
- Provides a seamless, void-free surface
- Approved for use on the London Underground and Overground
- NBS Source registered
- Joint width: 3–50mm | Depth: 20–200mm
- Lasts up to 40 years without re-grouting
- Works in light rain
- Shelf life: 8 months (unopened)
Suitable Paving Types
- Charcoal or grey porcelain (joints from 3mm)
- Granite setts
- Slate
- Darker sandstone and Indian Stone
- Yorkstone
- Clay pavers
- Concrete flags
- Limestone (including darker limestone when used with a temporary pre-sealer)
Flowpoint Smooth Charcoal vs Natural Grey — Which Do You Need?
| Flowpoint Smooth Charcoal | Flowpoint Smooth Natural Grey | |
|---|---|---|
| Best for | Charcoal/grey porcelain, granite setts, slate, darker stones | Pale porcelain, sandstone, limestone, Indian Stone, mixed packs |
| Joint width | 3–50mm | 3–50mm |
| Set time | 15 minutes at 20°C | 15 minutes at 20°C |
| Compressive strength | 49.6N/mm² | 49.6N/mm² |
| BS 7533 compliant | Yes | Yes |
Flowpoint Grades & Colours — Which One Do You Need?
| Grade | Colours Available | Joint Width | Joint Depth |
|---|---|---|---|
| Flowpoint Standard | Natural Grey & Charcoal | 5–50mm | 20–200mm |
| Flowpoint Premium Standard | Stone Grey, Limestone & Yorkstone | 5–50mm | 20–200mm |
| Flowpoint ECO | Natural Grey & Charcoal | 5–50mm | 20–200mm |
| Flowpoint Smooth | Natural Grey & Charcoal | 3–50mm | 20–200mm |
| Flowpoint Premium Smooth | Limestone, Stone Grey & Yorkstone | 3–50mm | 20–200mm |
| Flowpoint Fine | Natural Grey & Charcoal | 2–50mm | 20–200mm |
| Porcelpoint (for porcelain) | Stone Grey & Limestone | 2–50mm | 20–200mm |
Flowpoint Smooth Approximate Coverage Guide (per 25kg bag)
- Porcelain (600×900, 5×20mm joints): approx. 30m²
- Natural Stone Mixed Packs: approx. 12–20m²
- Granite Setts: approx. 1.5–2m²
For the most accurate calculation, use The Paving Experts' Flowpoint Calculator on the product page to estimate coverage for your exact paving size and joint width.
Frequently Asked Questions — UltraScape Flowpoint Smooth Charcoal
I'm Cleo, owner of The Paving Experts, with over 25 years in the construction industry working with businesses including Tarmac and Instarmac. I work alongside a small team of incredibly knowledgeable and caring individuals who share the same passion for getting it right. The FAQ answers below come from the questions we're asked every single day — so if yours isn't there, just give us a call.
1. What is UltraScape Flowpoint Smooth?
UltraScape Flowpoint Smooth is a rapid-set, flowable paving grout designed specifically for smooth paving stones and slabs. It produces a seamless, void-free joint that conforms to the requirements of BS 7533. Pre-mixed and supplied in 25kg showerproof bags, it requires only the addition of water on site — making it one of the fastest, most consistent ways to joint large areas of smooth or polished paving.
2. What is Flowpoint Smooth used for?
Flowpoint Smooth is used for jointing paving in a wide range of applications — from domestic patios and driveways to town centre pedestrian schemes, pathways and carriageways. It is suitable for natural stone, concrete flags and clay pavers, and is particularly well suited to smooth or polished surfaces where a seamless, void-free finish is required. It is ideal for large-scale projects where speed and consistency of application matter.
3. What is Flowpoint Smooth and how is it different from Flowpoint Standard?
Flowpoint Smooth is a rapid set flowable grout engineered for smooth paving stones and slabs where joints can be as narrow as 3mm — two millimetres tighter than Flowpoint Standard (5mm minimum). Its high fluid consistency produces a seamless, void-free joint that is particularly well suited to smooth or polished surfaces. The compressive strength, application method, water ratio and trafficking times are identical to Standard.
4. Why choose Charcoal over Natural Grey for Flowpoint Smooth?
Charcoal creates a bolder, more defined joint that works particularly well with charcoal or grey porcelain, granite setts, slate and darker natural stones. It gives a contemporary, high-contrast finish that frames the paving beautifully. Natural Grey is the more neutral option — if you're unsure which suits your stone, send us a photo and we'll advise.
5. What joint widths can Flowpoint Smooth be used for?
Flowpoint Smooth handles joints from 3mm to 50mm wide and 20mm to 200mm deep in a single application — narrower than Flowpoint Standard, which starts at 5mm. For joints narrower than 3mm, consider Flowpoint Fine (from 2mm) or Porcelpoint (from 2mm). Give us a call if you're unsure which grade is right for your project.
6. What is the set time for Flowpoint Smooth?
Flowpoint Smooth reaches initial set in 15 minutes at 20°C. Temperature is the key variable — colder conditions extend the set, warmer ones shorten it. Always use the thumb test before cleaning down — if the joint still feels soft, it's too early.
7. How long before you can walk on Flowpoint Smooth?
Flowpoint Smooth can accept light foot traffic after approximately 1 hour, depending on temperature. In colder conditions, allow a little longer before walking on the surface.
8. How long before vehicles can drive over Flowpoint Smooth?
Flowpoint Smooth can accept vehicular traffic after approximately 4 hours, depending on temperature. This makes it an excellent choice for driveways, pathways and carriageway schemes where downtime needs to be kept to a minimum.
9. Is UltraScape Flowpoint Smooth BS 7533 compliant?
Yes — UltraScape Flowpoint Smooth conforms to and exceeds the requirements of BS 7533. It is designed for rigid or bound, void-free paving joints and is NBS Source registered for ease of specification on commercial and public realm projects.
10. Can Flowpoint Smooth Charcoal be used on porcelain paving?
Yes — Flowpoint Smooth Charcoal is well suited to charcoal or grey porcelain paving, particularly where joints are 3mm or wider. Its high fluid consistency flows cleanly into tight joints without bridging or voids. For porcelain, we also strongly recommend a temporary pre-sealer such as Tile Rite Patio Prep to prevent grout haze on the polished surface.
11. Can Flowpoint Smooth Charcoal be used on natural stone paving?
Yes — Flowpoint Smooth Charcoal is suitable for granite setts, slate, darker sandstone, Indian Stone and Yorkstone. Always carry out a small trial on your specific stone first. For darker limestones such as black limestone, apply a temporary pre-sealer like Tile Rite Patio Prep to prevent oxidisation.
12. Can Flowpoint Smooth be used on concrete paving?
Yes — Flowpoint Smooth is suitable for concrete flags and is an excellent choice for any paving application requiring a rigid, bound, void-free joint. Its high fluid consistency means it fills joints in concrete paving quickly and consistently, with no need for hand-pointing.
13. Can Flowpoint Smooth be used on clay pavers?
Yes — Flowpoint Smooth is suitable for clay pavers. As with all stone types, we recommend a small trial area first, and for any absorbent surface, ensure the paving is thoroughly pre-soaked before application to prevent the grout being drawn in too quickly.
14. Is Flowpoint Smooth suitable for driveways and high-traffic areas?
Yes — Flowpoint Smooth is designed for applications including pathways, town centre pedestrian schemes and carriageways. With a compressive strength of 49.6N/mm² and vehicular trafficking possible after just 4 hours, it is well suited to driveways, commercial car parks and any surface that needs to return to use quickly.
15. Is Flowpoint Smooth suitable for large paving areas?
Yes — Flowpoint Smooth is specifically identified by Instarmac as ideal for large-scale projects. Its high fluid consistency allows large areas to be grouted efficiently — far faster than traditional hand-pointing. Working in manageable sections and keeping the surface misted is the key to a clean, consistent result across a large area.
16. How do you apply Flowpoint Smooth Charcoal?
Pre-soak the paving and remove all ponded water. Add 4.25 litres of clean water per 25kg bag and mix for 3–5 minutes until smooth and lump-free. Pour onto the paving and work into joints using a neoprene squeegee. Keep the surface misted throughout. Once initial set is reached, clean down with a brush and plenty of clean water. Mix only what you can place in approximately 4 minutes — never add more water or remix.
17. How much water do you add to a 25kg bag of Flowpoint Smooth?
Exactly 4.25 litres of clean water per bag. Mix for 3–5 minutes with a slow-speed drill and paddle mixer until smooth and pourable. Never add more water once mixing has started and never remix a batch that has begun to go off.
18. Is Flowpoint Smooth easy to mix?
Yes — Flowpoint Smooth is supplied as a fully pre-mixed dry-pack and only requires the addition of water on site. A slow-speed drill with a paddle mixer attachment is all you need. Mix for 3–5 minutes until smooth and lump-free. No specialist equipment required.
19. What colours does Flowpoint Smooth come in?
Flowpoint Smooth is available in Charcoal and Natural Grey. For a wider palette — Stone Grey, Limestone and Yorkstone — the Flowpoint Premium Smooth range offers the same performance in additional tones.
20. Can Flowpoint Smooth Charcoal be used with black limestone?
Flowpoint can cause oxidisation on some darker limestones such as black limestone — however, the new generation of temporary pre-sealers, such as Tile Rite Patio Prep Temporary Sealer, prevent this by creating a protective barrier between the stone and the grout. If you'd like advice on your specific stone, give us a call — we're happy to help.
21. Will Flowpoint Smooth Charcoal stain my paving?
Flowpoint Smooth is designed to be stain-free when applied correctly. Staining is not a product fault — it's typically caused by skipping a paving primer, not misting slabs during application, or over-watering the mix. Use a neoprene squeegee, keep slabs misted, and consider a temporary sealer such as Tile Rite Patio Prep for porous or textured stones.
22. Is Flowpoint Smooth permeable?
No — Flowpoint Smooth is a non-permeable cementitious grout. Once set, it does not allow water to pass through the joint. It must be used on a solid, non-permeable bed. If you need a permeable jointing solution, contact us and we'll point you in the right direction.
23. Can you use Flowpoint Smooth in the rain?
Yes — light rain is fine, but ensure the joints don't fill with rainwater before you begin. A damp day can actually be beneficial as it slows the set and gives you more working time. Do not apply during heavy rain or when frost is forecast within 24 hours.
24. Do I need to pre-seal my slabs before using Flowpoint Smooth?
If using a temporary pre-grout sealer (such as Tile Rite Patio Prep or Nexus ProJoint Pre-Grout): do not pre-soak the paving. The sealer acts as the protective barrier — water is not required until clean-down.
If not using a temporary sealer: thoroughly wet the paving with a hose spray before applying, then remove all standing or ponded water from the surface and joints — a leaf blower is ideal. The surface should be damp, not waterlogged.
25. What is the shelf life of Flowpoint Smooth?
8 months from the date of manufacture (printed on the bag, on the white strip on the side of the bag), for unopened, sealed bags stored in a cool, dry, frost-free area. Using the product after the declared storage period may increase the risk of an allergic reaction.
26. How much Flowpoint Smooth do I need?
Coverage varies depending on joint size and depth, paving stone size, surface absorption and wastage. Use the Flowpoint Calculator on this page for an accurate estimate, or call us and we'll work it out for you.
27. How long does Flowpoint Smooth last?
When applied correctly on a properly prepared bed, Flowpoint Smooth Charcoal can last up to 40 years without the need to re-grout.
28. How do I tell the Flowpoint grades apart on delivery?
The bag colour tells you the grade at a glance. Flowpoint Smooth bags are orange and blue. For reference across the full range: Standard is black and orange; ECO is orange and green; Fine comes in tubs rather than bags, with the lid colour indicating the colour variant. On all bags, the specific colour variant (Natural Grey or Charcoal) is printed on the white strip on the side of the bag.
Watch the video...
Please note: The videos below show Flowpoint Fine being applied. The mixing and application principles are exactly the same for Flowpoint Smooth — the only difference is the water ratio. Flowpoint Fine and Porcelpoint require 3.4 litres of clean water per 20kg bucket, whereas Flowpoint Standard, Smooth, ECO and Premium require 4.25 litres of water per 25kg bag.
Want to learn more about UltraScape Flowpoint?
Read our blog post 'What is Flowpoint', or for more in-depth questions see our Flowpoint FAQs.
Want to order a pallet quantity?
View our 56-bag full pallet or 40-bag part pallet — both include free standard delivery.
Need a paving primer & bedding mortar?
We recommend using the full UltraScape BS 7533 Mortar Paving System — a range of high-performance materials that meet and exceed the strict demands of BS 7533. Including rapid-strength fine bedding concrete EcoBed, priming slurry Pro-Prime, and flowable jointing grout Flowpoint.
If you'd like to know more about Flowpoint Smooth Charcoal, which grade is right for your project, or need help colour-matching — don't hesitate to get in touch or call us on 0330 122 1025. We're a small team but we know our products inside out, and we're always happy to help.
Flowpoint Smooth Charcoal — Full Technical Information
Product Overview
UltraScape Flowpoint Smooth Charcoal is a rapid-setting, flowable, cement-based paving grout with a finer aggregate finish for external use. Its finer particle size allows it to fill joints from just 3mm — making it the preferred choice over Flowpoint Standard for porcelain paving, smooth natural stone, and any application requiring a tighter joint. It conforms to BS 7533 and delivers the same proven performance as the wider Flowpoint range, in a bold charcoal tone suited to darker stones and contemporary paving schemes. Approved for use on the London Underground and Overground, and NBS Source registered.
Performance Data
| Property | Value |
|---|---|
| Classification | BS 7533 |
| Compressive strength | 49.6N/mm² |
| Bond strength | Exceptional |
| Shrinkage | Shrinkage compensated |
| Initial set | 15 minutes at 20°C |
| Open to foot traffic | 1 hour |
| Open to vehicular traffic | 4 hours |
| Expected service life | Up to 40 years |
| Permeability | Non-permeable (impermeable bed required) |
| Weather resistance | Can be applied in light rain |
| Frost resistance | Do not apply below 3°C or if frost expected within 24 hours |
Application Data
| Property | Value |
|---|---|
| Water requirement | 4.25 litres per 25kg bag |
| Mixing time | 3–5 minutes |
| Working time after mixing | Approx. 4 minutes — mix one bag at a time |
| Joint width | 3–50mm |
| Joint depth | 20–200mm (single application) |
| Supply format | 25kg showerproof bags (pre-mixed dry-pack — just add water) |
| Colours available | Charcoal & Natural Grey |
Coverage Guide (approximate, per 25kg bag)
| Paving Type | Approximate Coverage |
|---|---|
| Porcelain Paving (600×900, 5×20mm joints) | approx. 30m² |
| Natural Stone (mixed pack) | 12–20m² |
| Granite Setts | 1.5–2m² |
Coverage varies depending on joint width, depth, stone size, surface absorption and wastage. Use the Flowpoint Calculator on this page for an accurate estimate.
Suitable Substrates
- Charcoal or grey porcelain (joints from 3mm)
- Granite setts
- Slate
- Darker sandstone and Indian Stone
- Yorkstone
- Clay pavers
- Concrete flags
- Limestone (including darker limestone when used with a temporary pre-sealer)
Note: Flowpoint Smooth is not recommended for use on some darker limestones (e.g. black limestone) without a temporary pre-sealer, as it may cause slight oxidisation. Contact us for advice on your specific stone.
Approvals & Certifications
- Conforms to BS 7533
- Approved for use on the London Underground and London Overground
- NBS Source registered
- Part of the Flowpoint range — in use for over 25 years across public realm, commercial and domestic projects worldwide
Storage & Shelf Life
- Shelf life: 8 months from date of manufacture (printed on the white strip on the side of the bag)
- Store in a cool, dry, frost-free area in unopened, sealed bags, clear of the ground
- Using after the declared storage period may increase the risk of an allergic reaction
Health & Safety
- Contains cement — wear appropriate PPE including gloves and eye protection
- Wet cement can cause serious skin burns — avoid prolonged skin contact
- Wash hands and exposed skin thoroughly after use
- Keep out of reach of children
- Full Safety Data Sheet (SDS) available on request or from the UltraScape website
For the full technical datasheet, download the PDF here. For project-specific advice, get in touch or call us on 0330 122 1025.
Delivery & Returns Info
Our delivery charges are calculated based on the size and weight of your order. When you add items to your basket, the delivery charges are displayed. Small orders are distributed via courier; larger orders via Pallet Network. Collection is available from our Tamworth depot by request (contact us first to arrange on 0330 122 1025).
Please note, there is a slight surcharge for areas that are outside of our locality, charges calculated at checkout.
| Weight and size | Next Working Day* Order before 1PM (excl. VAT) |
Standard 3-5 Working Day (excl. VAT) |
|---|---|---|
| 0-13KG (1 small bag/tub) |
£14.00 | £9.00 |
| 13.01-25KG (1 large bag/tub) |
£16.00 | £10.00 |
| 25.01-50KG (2 bags/tubs) |
£26.00 | £19.00 |
| 50.01-75KG (3 bags/tubs) |
£36.00 | £28.00 |
| 75.01-100KG (4-5 bags/tubs) |
£46.00 | £37.00 |
| 100.01-249KG (6-9 bags/tubs) |
£60.00 | £45.00 |
| 249.01-750KG (10 bags plus) |
£68.00 | £48.00 |
| 750.01KG plus (30 bags plus) |
£75.00 | £55.00 |
| Full Pallets (56 bags/52 tubs) |
£88.00 | Free of charge |
| Next Working Day delivery (Premium 1-2 Working Day Service) | +avg. £5-10 Extra. Click here for prices |
|---|---|
| Scotland Delivery Service (Deliveries into some parts of Scotland can take 8-10 working days) | Click here for prices |
| Local Delivery & Click & Collect: | Email: orders@thepavingexperts.co.uk |
Delivery Information
- Prices apply to mainland England and Wales. Scottish delivery slight surcharge.
- Orders are packed and dispatched Monday–Friday (excluding weekends & public holidays).
Next Working Day Delivery
- Order before 1PM → same-day dispatch.
- Order after 1PM or on weekends/bank holidays → next working day dispatch.
- You'll receive tracking updates via email/SMS if you provide your details.
Delivery Examples
- Mon before 1PM → Packed Mon, delivered Tue.
- Mon after 1PM → Packed Tues delivered Wed.
- Fri before 1PM → Packed Fri, delivered Mon.
- Fri after 1PM/weekend → Packed Mon, delivered Tues (or Wed after a bank holiday).
- Standard Service: 3–5 working days.
Notes
- Occasional delays due to manufacturing, supply, or courier issues may happen, but we'll keep you informed.
Returns, cancel up to 14 days from date of delivery. Product to be returned in the same condition & packaging. No returns for cementitious & perishable products. You are responsible for the cost of returning goods to The Paving Experts, 20% admin restock fee applies. Need further info, click here.
For further detailed delivery information click here →
How to Mix & Apply UltraScape Flowpoint Smooth Paving Grout
Step 1 — Preparation
There are two approaches depending on whether you are using a temporary pre-grout sealer or not:
Without a temporary pre-sealer (standard method):
- Ensure joints are clean and free from debris, dust and loose material.
- Thoroughly pre-soak the paving surface and joints with water — the paving must be properly wet before you begin.
- Then remove all standing or ponded water from the surface and from within the joints — a leaf blower is ideal for this. The paving should be damp, not waterlogged. This is the key step: the paving needs to be wet enough to prevent the grout drying out too quickly, but any excess standing water will over-dilute the mix and weaken the joint.
- Keep the surface moist throughout application by misting with a soft spray of water as you work — do not allow it to dry out.
With a temporary pre-grout sealer (e.g. Tile Rite Patio Prep or Nexus ProJoint Pre-Grout):
- Apply the temporary sealer to the paving in advance and allow it to dry as per the product instructions.
- Do not pre-soak the paving with water. The temporary sealer acts as the protective barrier at this stage — water is not required until clean-down.
- Remove any standing water from the joints using a leaf blower before grouting begins.
- Always carry out a small trial area first to ensure compatibility with your stone type.
Step 2 — Mixing
- Add 4.25 litres of clean water per 25kg bag into a clean bucket or mixing vessel.
- Gradually add the Flowpoint Smooth powder to the water (not the other way around) and mix for 3–5 minutes until a smooth, lump-free, pourable consistency is achieved. Use a slow-speed drill and paddle mixer for best results.
- Only mix what you can apply in approximately 4 minutes — do not store liquid mortar.
- Never remix or add extra water once mixed. Doing so will weaken the final joint and may cause staining.
Step 3 — Application
- Pour the mixed grout directly onto the paving surface.
- Using a neoprene squeegee, carefully force the mortar into the joints, working it across the surface repeatedly. The finer aggregate of Flowpoint Smooth flows particularly well into narrow joints — work methodically to ensure all joints are fully filled. Top up any joints where the mortar has slumped after initial placement.
- Use the squeegee to remove as much excess mortar as possible from the surface as you go.
- If not using a temporary pre-sealer, keep the surface constantly moist using a soft spray of water throughout application. If using a pre-sealer, water is not required until clean-down.
- Once the jointing mortar has reached its initial set and hardened sufficiently, clean the paving surface thoroughly using a brush and copious amounts of clean water. No mortar must be allowed to remain on the surface of the paving.
- Wash all tools frequently during application.
Step 4 — Trafficking
- Foot traffic: after 1 hour (at 20°C)
- Vehicular traffic: after 4 hours (at 20°C)
- Cool temperatures retard set; warm temperatures accelerate it. Avoid applying in direct sunlight or during frost.
Technical Specification (Mixing Tab Summary)
| Property | Value |
|---|---|
| Water requirement | 4.25 litres per 25kg bag |
| Mixing time | 3–5 minutes |
| Working time after mixing | Approx. 4 minutes |
| Initial set | 15 minutes at 20°C |
| Open to foot traffic | 1 hour |
| Open to vehicular traffic | 4 hours |
| Joint width | 3–50mm |
| Joint depth | 20–200mm (single application) |
Important Precautions
- Wear appropriate PPE — avoid skin and eye contact. Wet cement can cause serious burns to the skin.
- Never remix or add extra water to the mix once it has been prepared.
- If you are not using one of UltraScape's pre-bagged bedding mortars, take care when selecting aggregates or sands for your site-batched bedding mortar. Some bedding mortars can leach pigment into the Flowpoint, causing variation in joint colour. If in doubt, give us a call — we're happy to advise.
- Do not apply in temperatures below 3°C or if frost is expected within 24 hours.
- Do not apply in direct sunlight — the product will set rapidly and may be difficult to clean down.
- Store in a cool, dry, frost-free area. Shelf life: 8 months from date of manufacture (printed on the white strip on the side of the bag).