Creating or revamping a patio or paved area? Deciding on which grout to use is just as important as choosing the paving stones themselves. This no-nonsense guide to patio grouts reviews all the pointing options so you can decide on the best one to suit your project.
Which is ‘best’ grout can be the source of much debate among professional landscapers and paving experts. Although sometimes it comes down to personal preference, there are many other factors at play.
Key questions when determining which grout is best can include: What are the joint widths? Is it a permeable project? Do you want a sleek or sanded finish? Will the patio be used as a driveway? Will it need to withstand other heavy loads? Do you prefer a low-maintenance grout? And, crucially, what is your skill set for installation?
We’ll look at the four main types of grouts to choose from so you can quickly weigh-up which type suits you best.
What are the different types of grout?
So what are the different types of patio grouts available?
Outdoor patio grouts can come in the form of:
- Sanded brush-in grouts
- Cement-based slurry grouts
- Epoxy resin grouts – either single-part or two-part mixtures
- Exterior tiling grouts, usually for porcelain pavers
Each of these grouts are available as off-the-shelf products.
Traditional mortars consisting of sand, cement and water can be made up yourself. However, applying these traditional mixes can be very labour intensive, if not back breaking (it can involve pointing on your hands and knees).
Also, traditional mortars don’t offer the peace of mind or guarantee that can come with an off-the-shelf mortar.
Let’s look at these four types of grouts in detail to help you decipher which one is best for your patio project.
Sanded brush-in grouts
A simple sanded or brush-in grout consists of a dry sand and cement mixture. In the industry, it can be referred to as a single-part polymeric compound.
These premixed permeable grouts are incredibly easy to install and don’t require any type of specialist equipment. Simply pour straight from the tub onto a wet patio and sweep the mixture into the joints.
Another big plus about brush-in grouts is their cost-effectiveness when compared with other grouts.
Brush-in grouts like EASYJoint and PremJoint come in a range of colours. Whether your paving is a light limestone or dark granite, you can easily pick a shade that either compliments or contrasts with the stones.
Sanded Brush-in Grouts | |
Pros | Cons |
| A very cost-effective grout | Not as durable as other grouts |
| Extremely easy to install | Many unable to withstand vehicle weight |
| No specialist equipment | Many formulas are not weed-resistant |
| Use with all types of paving stones* | Never pressure-wash the joints |
| Perfect for permeable projects | |
| A range of colour options | |
* Sanded brush-in grouts can generally be used with any type of paving stone. Always check the product specification to be sure before buying
Saying all of that, there are a couple of downsides to brush-in grouts that it’s important to weigh-up when finding the best grout for you.
Firstly, the sanded nature of brush-in grouts can make the joints prone to weed growth. Moving forward, this can involve more ongoing maintenance on the homeowner’s part than what would be expected with the other grouts mentioned below.
Secondly, most brush-in grouts are not durable enough to withstand heavy loads and particular vehicle traffic.
One exception of a brush-in grout that can be used for driveways is PremJoint.
However, when used for driveways the grout must be installed as a dry product and the bedding mortar used must be impermeable.
This will help to ensure that the product has the strength to hold light vehicle traffic. But if you wanted a permeable patio, it will sadly make your driveway project impermeable.
See epoxy resin mortars below for grouting solutions that are permeable and extra-strong solutions, and can withstand heavy loads.
Installation tips for brush-in grouts
Brush-in grouts are the perfect choice for first-time patio installers, or even for those looking for a grout that’s simple and effortless to work with.
Before installation, simply wet the pavers using a hosepipe to dampen them thoroughly. Try to avoid any ponded water, and likewise any dry patches.
Then, pour the bucket of brush-in grout into the paving joints to fill them up. Although you can do this task easily with a long-handled broom, the task is made much easier with a specialist squeegee (also long-handled).
That’s all that’s needed for installing a brush-in grout. However, if you want neater and longer lasting joints, ‘strike off’ the joints once they have dried a little using a trowel or finishing bar.
Cement-based slurry grouts
When a patio’s durability and longevity are high on your list of priorities, cement-based slurry grouts are certainly the ones to consider.
Due to their cementitious formulas, slurry grouts have the strength and longevity to withstand whatever life throws at them, in terms of weather, weight, vehicle traffic – and even those pesky weeds.
Essentially, slurry grouts are wet and flowable mixtures. They are poured over the laid paving slabs and manipulated into the joints using the squeegee we mentioned earlier.
For some slurry grouts, like Flowpoint, the manufacturers are so confident in their formulas that they offer a guarantee of up to 40 years (you must follow the recommended installation practices).
In fact, Flowpoint meets and exceeds the British Standard BS7533. This is a valuable seal of approval for contractors and project managers wanting to know that the grout has gone through in-depth checks and tests to assure its robustness.
Simply put, these cement-based grouts are built to last.
Cement-based slurry grouts | |
Pros | Cons |
| Cost-effective | Not for permeable projects |
| Extremely durable | A paddle mixer often required |
| Withstands vehicle traffic | Joints may be prone to moss/algae |
| Stops weed growth | |
| Easy to install once you know how | |
| Rapid-setting | |
| Some can be applied in all weathers | |
| Pressure-washer safe | |
| Use with most types of paving stones* | |
| A range of colour options | |
* Commonly, slurry grouts are not suitable for installing on some darker limestone, such as black limestone. Always check the product description before buying.
While slurry grouts are all about strength and durability, they are an impermeable grout. As such, they cannot be used for grouting permeable patios that need rainwater and surface water to freely drain through.
If you’re laying a patio as a driveway in the UK, you may want to avoid using an impermeable grout. By law, new driveways and front garden patios over a certain size must be permeable or have drainage features incorporated – otherwise you will need planning permission.
Read on for a permeable grout option that can still withstand heavy loads and vehicle traffic.
Installation tips for slurry grouts
When compared with a traditional mortar mix, slurry grouts are far easier to install.
Despite this, you do need to have a little know-how before installing these products. And especially as many of the formulas, such a Flowpoint and Fuga-Pave set rapidly. Ideally, they should be applied quickly and confidently.
Slurry grouts are commonly used by professional landscapers and patio installers who regularly install patios.
Certain specialist equipment, such as a plasterer’s whisk, is needed to combine the dry mix with water.
Ideally, you will have two people for the job: one to keep the area constantly wet, the other to ‘squeegee’ the formula into the joints.
See our expert guide on how to apply Flowpoint slurry grout to get a good snapshot of what’s involved in the process.
Epoxy resin grouts
Historically speaking, epoxy resin grouts were a grout chosen by professionals.
But due to their ease of use – not to mention their hard-wearing durability – today, they are becoming a grout of choice for all types of paving installers, skilled and beginners alike.
Epoxy grouts either come as a two-part epoxy resin, or a single part mix.
Two-part epoxy mixes are typically made up of a bag of specialist aggregate sand-based material and two small bottles of resin and hardener. The formulas are simply combined together in a bucket to form a slurry mix before being applied to a wet patio surface.
Single mixes of epoxy grouts are simply the resin and hardener. They are commonly used as grouts for narrower joints such as porcelain paving.
Some epoxy grouts, such as Joint-It Dynamic and ProJoint Titan, are loved for their versatility in the paving world.
Amazingly, these particular epoxy resins can be used as grouts for both permeable and impermeable projects. All you need to do, for whichever type of project you’re working on, is simply use the appropriate bedding mortar – permeable or impermeable.
So with these epoxy resin grouts you can create a robust, fully permeable and eco-friendly driveway without needing planning permission.
Impressively, ProJoint Titan has been made to withstand up to 10 tonnes in weight without cracking or breaking.
Epoxy resin grouts | |
Pros | Cons |
| Extremely durable | Can be more expensive |
| Withstands vehicle traffic | Sanded mixes may need a paddle mixer |
| Stops weed growth | |
| Some can be used for permeable projects* | |
| Easy to install once you know how | |
| Waterproof and low maintenance | |
| Pressure-washer safe | |
| Use with most types of paving stones | |
| A range of colour options | |
* Only certain epoxy resin grouts, like Joint-It Dynamic and ProJoint Titan, can be used for permeable projects. Check the full description before purchasing.
Another great bonus about epoxy grouts, especially for homeowners, is the lack of ongoing cleaning and maintenance they require.
The hardened formula is waterproof and resistant to weeds, algae, mould, chemical stains and frost.
On the downside, epoxy resin grouts can be more expensive than other grouting options.
Installation tips for epoxy grouts
Much like cement-based slurry grouts, sanded epoxy grouts are a two-person job. That’s one person to keep the area wet, the other to shimmy the formula into the joints.
Generally, you mix together the aggregate and sand mixture with the resin and hardener in a bucket using a paddle mixer. Once the pavers are moist, the combined formula is applied to each of the joints using a squeegee.
As with slurry grouts, it’s crucial to keep the paving moist during the whole process. See our DIY guide for resin grouts to find out more.
Exterior tiling grouts
Although most exterior tiling grouts can be applied to all types of joints, they are typically associated with narrow joints.
Exterior tile grouts contain finer aggregates for sleek outdoor paving tiles such as porcelain.
They may come in a tub and are simply mixed with water before being applied to the joints using a rubber float or squeegee. A washboy may be used to clean the surfaces of the tiles. Finally, a soft cloth is used to remove any remaining spots of adhesive.
Whether you use an exterior tiling grout really depends on the size of your joints.
ProJoint Porcelain Paving Grout, for example, is a flexible, high-performance grout for porcelain pavers. It can be used for joint widths from 2mm to 20mm wide.
With the popularity of porcelain patios, many cement-based slurry grouts and epoxy resin grouts include product variations for these types of tiles and joint sizes.
Flowpoint Fine is a slurry grout specially formulated for narrow joints and porcelain tiles.
Joint-It Porcelain Epoxy Grout can be used with smaller paving joints from as small as 1mm wide and from 10mm deep.
Common questions
Do I need to seal paving before grouting?
As a general rule, highly porous paving slabs, such as slate, black or blue limestone or flamed/honed black granite, must be pre-sealed before grouting.
Other grouts may suggest pre-sealing the pavers for other types of natural stone and concrete paving.
Always read the product’s instructions and technical datasheet first.
Read our article on sealing patios for more info.
Which bedding mortar should I use?
While choosing the right grout will help to ensure the longevity of your project, patios still need a solid and stable surface for them to stand the test of time.
Patio slabs must be laid on a full-contact bed using a quality bedding mortar or mortar mix.
Read more about creating a solid foundation for a patio.
Do I need to use a primer?
We strongly advise on priming the underside of each slab before securely fixing it to the bedding layer below.
A primer helps to reduce slippage of the patio slabs. This, in turn, helps you to avoid mortar cracks and breaks. For porous paving slabs, a primer is also a crucial step for avoiding efflorescence and picture framing stains on the slabs.
Read more about why you should use a primer.
Before you go...
This article is a general summary of the main types of grouting compounds available. Product specifications do differ. You may find that some specific grouts under these categories don’t feature all the highlights we’ve mentioned – and others have features that we haven’t specified.
We put a lot of thought into making sure that our product descriptions are accurate and include all the answers you need to make a confident decision. Full technical datasheets are available – get in touch if there’s one that you need.
Likewise, if you’d prefer to speak to a friendly member of our team to see which paving grout may suit your project best, do pick up the phone and call us. We’re here to help and can offer great savings on bulk orders.
