Nexus ProJoint Fusion | All-Weather Brush-In Joint Compound for Natural Stone & Concrete Paving

'One of the Best All-Weather Paving Joint Compounds on the Market — Cement Free, Weed Resistant, and Perfect Results Every Time — Whatever the Weather'

Nexus ProJoint Fusion is one of the best all-weather paving joint compounds on the market — an excellent example of a product that genuinely delivers on its promises. Quick and easy to use, Fusion allows an untrained hand to consistently deliver perfect joints every time, whatever the weather. It produces a weed-free, frost-resistant joint without staining the paving — saving time, money and the need to redo the job a year later. It's a product that has built a loyal following among both contractors and DIYers who keep coming back because it simply works.

Resin-based, premixed brush-in compound for joint widths of 3mm and above and depths of 25mm, suitable for natural stone, concrete slabs and setts — Fusion is the go-to choice for patios, paths and pedestrian areas where reliable, weather-tolerant performance matters.

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 jointing products come and go. Fusion is the one we reach for when someone needs a dependable, easy-to-use compound that works in real UK weather conditions.

If you're grouting natural stone or concrete paving and want a product that's weed-resistant, frost-resistant, cement-free and usable in light rain — Fusion is the product we'd confidently recommend. Available in four colours: Neutral (buff), Mid Grey, Basalt and Black. If you're unsure which colour suits your paving, give us a call — samples are available on request.

Note: Fusion is not recommended for porcelain paving. For porcelain, please use ProJoint RapidFlow — the application is the same, but RapidFlow cures harder and bonds better to the dense surface of porcelain tiles.

Fusion is a premixed, ready-to-use resin jointing compound — no mixing required. Supplied in a 15kg tub containing two 7.5kg bags to reduce waste. Soak the paving, brush the compound into the joints, mist with water to flush it down, then sweep off the excess. Cures on exposure to air. Cement free and non-hazardous.

Is Fusion Right for Your Paving? Permeable vs Non-Permeable Beds

Before choosing a jointing compound, you need to answer one critical question: where is the water going to go?

Your paving construction determines which product is correct — and getting this wrong can trap moisture, cause staining, algae growth, cracking and joint failure.

• Permeable paving — water drains through the joints into the ground below. Typically a sand and cement bed (5:1 or above) on a free-draining sub-base. ✅ Fusion is the right choice.
• Non-permeable paving — water cannot drain downwards and must run off across the surface. Typically paving on a solid concrete base or impermeable sub-base. ❌ Fusion is not suitable — for porcelain on a non-permeable bed, see ProJoint TileJam, UltraScape PorcelPoint or FUGA-PAVE XP instead.

Fusion cures by drying out — water must have a clear route of escape through the bed. Using Fusion on an impermeable base traps moisture in the joints, which contributes to freeze/thaw damage in cold weather, causes joints to weaken and crack, and creates the damp conditions in which algae and lichen thrive.

Not sure which system you have? Give us a call — 0330 122 1025. It's a quick conversation and it could save you a very expensive mistake.

Key Benefits

• All-weather formula — usable in light rain, no need to wait for a dry day
• Suitable for natural stone, concrete slabs and setts — joint widths 3mm and above
• Cement free and non-hazardous — safer to handle, no efflorescence risk
• Weed free joint — resin binder leaves no loose material for weeds to take hold
• Frost resistant — suitable for UK climate conditions
• Permeable — allows water to drain through, reducing surface water and pooling
• No staining — won't mark the paving surface when applied correctly
• Pre-mixed and ready to use — ideal for both DIY and contractor use
• Foot traffic in 12 hours — fast turnaround in dry ambient conditions
• 4 colours: Neutral (buff), Mid Grey, Basalt, Black
• 15kg tubs supplied in 2 x 7.5kg bags to reduce waste

Technical Information

Download the technical datasheet (PDF)

Coverage — Approximate per 15kg tub

Based on average 600 x 600mm slabs

• Joint 5mm wide x 25mm deep: 20m²
• Joint 10mm wide x 25mm deep: 10m²
• Joint 15mm wide x 25mm deep: 6.67m²

Preparation

Ensure the surface of the paving is clean prior to application. Check the joints are cleaned out to a depth of 25mm, observing a minimum joint width of 3mm. Paving should be firmly bedded and stable on a permeable bedding mix prior to filling the joints — as Fusion cures when it dries out, water and rain must have a route of escape.

For sensitive or sawn paving, we recommend using ProJoint Pre-Grout Sealer prior to application of Fusion.

Application

1. Apply ProJoint Fusion when the surface temperature is between 3°C and 25°C. If your paving is wet cast concrete, see inside the tub for additional advice.
2. Liberally soak the paving.
3. Empty the mix evenly onto the surface and work quickly into the joints using a brush or squeegee.
4. Mist the surface and compound with a soft spray of water to flush the material down into the joints. Top up any low joints and repeat as necessary.
5. Once the water has drained away, sweep the paving with a fresh soft brush at 45° to the joints and remove any excess. A trowel or iron can be used to achieve a traditional finish if required.
6. Clean all tools with water after use.
7. Leave to cure. Fusion cures on exposure to air — as a guide, foot traffic can be accepted 12 hours from installation in dry ambient conditions. Cold temperatures and wet weather can delay curing significantly.

This product can be used in light rain, but prolonged heavy rain will delay the curing process and increase the risk of fluid damage.

Note: ProJoint Fusion may highlight and enhance the natural surface colours and textures of the paving — this can be especially noticeable on grey paving including granite, so a test area is advised before use. It is important to spread the mix across the total paving area to ensure any potential effect is uniform. This is a temporary effect — weathering and foot traffic accelerate its disappearance.

Frequently Asked Questions

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.

Is Fusion suitable for non-permeable paving?
No — Fusion is designed for permeable, free-draining beds only. If your paving is on a solid concrete or impermeable sub-base, you need a product designed for non-permeable beds instead. For porcelain, we'd recommend ProJoint TileJam, UltraScape PorcelPoint or FUGA-PAVE XP. Not sure which system you have? Call us — it's a quick but important question to get right.

How long does Fusion take to cure?
Fusion typically cures enough for foot traffic in about 12 hours in dry ambient conditions. Curing times can vary depending on the weather — colder and wetter conditions can delay the curing speed significantly. Full strength is reached at 28 days.

What is the best way to maintain my joints?
Keeping your paving joints clean is simple — sweep the area regularly to remove dirt, leaves and debris, which helps stop weeds from taking root. For a deeper clean to remove algae and dirt, our ProJoint Black Spot and Algae Remover will blast through it.

Can it be used on porcelain tiles?
Fusion isn't recommended for porcelain tiles — porcelain needs a specialist jointing compound due to its density. We'd recommend ProJoint RapidFlow for porcelain on permeable beds, or ProJoint TileJam, UltraScape PorcelPoint or FUGA-PAVE XP for non-permeable beds.

What weather conditions can I apply Fusion in?
Fusion can handle light rain, so no need to panic if the skies turn grey. Avoid applying it during heavy rain or freezing temperatures as it won't set properly. Apply when surface temperature is between 3°C and 25°C.

Can I open the tub and re-use it on a later date?
Once opened, the air will start the curing process. To stop this, put any excess material back in the tub and submerge it in water — this cuts out the oxygen and can give you up to a month of extra usage.

Where is Fusion used?
Fusion is perfect for natural stone and concrete patios, paths and other areas with foot traffic only. It is not suitable for vehicular areas or porcelain — for driveways, see ProJoint TITAN; for porcelain, see ProJoint RapidFlow.

Is Fusion permeable?
Yes — the primary benefit of permeable resin jointing compounds is their ability to let water pass through, reducing surface water and preventing pooling.

Why should the bedding mortar be permeable?
Fusion cures when it dries out, so water must have a route of escape. A permeable sub-base also allows water collecting in the joints to drain freely, stopping it from building up and becoming stagnant — stagnant water can soften the binder over time and encourage algae growth.

When you say permeable bedding/base mix, what does this mean?
A 5:1 ratio of sand and cement (or above) is classed as permeable. Using a specific permeable bedding or base mortar is also acceptable.

Can you pressure wash Fusion?
Yes, but only after it's fully cured (approximately 30 days). Use a fan nozzle and keep the pressure washer at a safe distance from the surface.

What's the difference between Fusion resin and epoxy?
Fusion is a resin-based compound that cures with air exposure, making it user-friendly and perfect for DIYers. Epoxy compounds like ProJoint TITAN are chemically cured, offering extra strength for heavy-duty or vehicular jobs but requiring more careful application and the correct weather conditions.

Note: As sand is a natural product, some minimal colour variance may occur. Colours shown are representative only — samples are available on request. Contact us for samples.

Need Some Help?

See our paving FAQs or get in touch — we're always happy to help. Call us on 0330 122 1025.

• Brand: Nexus
• SKU: TPE-NXFUSBAS15KG
• Weight: 15.0 kg / 33.07 lb