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Jointing and Pointing For Paving (Sand & Cement Mix)

grouting a patio

Pointing your patio is not just about aesthetics; it’s also about ensuring the longevity and durability of your paving. The hard work and meticulous attention invested in laying a patio underscore the importance of patio pointing. The right-pointing mix can protect the underlying bedding course and sub-base, prevent weed growth and enhance the overall visual appeal of your patio. In this guide, we delve deep into patio pointing, exploring traditional and modern techniques.

1.Dry Brush Grouting

Dry brush-in, often compared to wet grouting, relies entirely on having a moisture-free setting. For this method to work effectively, both the mortar mixture and the pavement surface must be completely devoid of water. This ensures that the sand/cement mix fills the gaps uniformly.

The surface of the pavement needs to be thoroughly dry. Even a slight moisture can make the mixture adhere undesirably, leading to potential stains. This technique is most effective and recommended during dry summer days.

For the best results, use building sand that leans toward the dry side. Another option is Kiln Dried Jointing sand. While some professionals might prefer using coarser sands, it’s worth noting that this choice can result in a rough texture when applied in dry grouting situations.

Dry brush grouting


How much sand and cement mix for paving joints?

The mix is precise: a 3:1 ratio of sand to cement, with a strict no-water rule. This ensures a consistent, uniform colour in the resulting powder, signifying a thorough blend of the components. Once prepared, this mixture is evenly spread over the paving surface and gently swept into the joints using a soft brush.

When it comes to the “dry brush-in” technique, there’s a notable challenge. The weight of the dry sand/cement mix is so light that it often doesn’t settle well into the joints. Instead, it tends to sit fluffily, not presenting a solid appearance. However, skilled contractors have a workaround. They employ a pointing bar or a trowel blade to firmly press the mix, ensuring it compacts well into the joint. This pressing and brushing-in process is repeated until the joints are satisfactorily filled.

There’s also another method that some consider more straightforward. After filling the joints, the surface is lightly misted with clean water. This not only helps the dry mix settle into the joint but also provides the slight moisture needed for the cement to start setting. However, this method has its limitations. Once the surface is damp, adding more dry mix becomes challenging. While on a scorching summer day, the surface might dry quickly, allowing for multiple rounds of this process, such ideal conditions are rare throughout the year.

Do patio sand and cement joints need to be wet?

Dry brushing-in, if not done correctly, can lead to subpar joints. Without proper wetting, the outcome is often a fragile, short-lived filler that can become a haven for weeds. Beware of contractors who neglect this, as they might leave you with a deteriorating patio after pocketing their payment.

Packaging and filling the joints adequately before introducing any water is essential for a quality joint. While this method can yield decent results, it still might not match the durability of a wet slurry joint. Combine dry brushing-in with freshly buttered joints during flag laying for the best outcome. This “butter mortar” (a typical wet mortar) provides the needed moisture for the dry mix to set. Ensure the dry mix is firmly pressed into the joint alongside the butter mortar for a long-lasting, sturdy joint.

2.Brush-In Jointing Compound

Brush-In Jointing Compound, often a blend of ready-mixed sand and cement, offers a modern twist to the age-old method of dry brush grouting. Tailored explicitly for the purpose of filling in the spaces between paving slabs, this compound is becoming a go-to choice for many homeowners and professionals alike.

Its rise in popularity can be attributed to several factors. Firstly, being pre-mixed, it eliminates the guesswork and potential inconsistencies that can arise when mixing your own sand and cement. This ensures uniform consistency and quality throughout the application. Secondly, its user-friendly nature means even those new to patio pointing can achieve professional-looking results.

Moreover, the compound often has added benefits, such as weed inhibitors, which prevent unwanted growth between the slabs. It also tends to be more resistant to the elements, ensuring longevity and reducing the need for frequent touch-ups. Lastly, its availability in various shades allows homeowners to choose a colour that complements their pavers, enhancing the overall aesthetic appeal of the patio.

AspectBrush-In Jointing CompoundTraditional Brush-In
Base ComponentsReady-mixed sand and cementManually mixed sand and cement
ConsistencyUniform due to pre-mixingVaries based on manual mixing
Application EaseUser-friendly, suitable for beginnersRequires more expertise for consistency
Additional BenefitsWeed inhibitors, weather-resistantDependent on mix and external products
Colour OptionsAvailable in various shadesLimited to sand and cement’s natural colour
LongevityOften more durable due to consistent mixDependent on quality of manual mix
A table comparing brush in jointing compound to traditional brush in grout.

3.Two-Part Epoxy Jointing Mortar

The two-part epoxy jointing mortar presents a sturdy alternative for patio pointing. Renowned for its durability, it’s apt for various surfaces, including driveways. This method is centred on the amalgamation of two elements: a resin and a hardener, which together produce a mortar that fills the gaps between paving slabs.

To utilise this method, firstly ensure the patio surface is clean, with all gaps between slabs free from debris or loose materials. Given the viscous nature of the mortar, it’s vital to prevent any seepage from open edges. This can be achieved by either haunching the edges or using putty to seal the gaps. The entire patio area should be dampened and kept moist during the application to delay the mortar from setting prematurely.

Once the surface is prepped, mix the two components of the mortar as directed by the manufacturer. The mortar can then be applied to the gaps with a squeegee, ensuring they are filled thoroughly. The semi-fluid consistency of the product means it will naturally settle into the gaps without the need for trowelling. It’s crucial to wash off any surplus mortar from the paving slabs before it dries. After the mortar solidifies, which typically takes between 24-48 hours, the patio is ready for use.

AspectTwo-Part Epoxy Jointing MortarTraditional Brush-In
Base ComponentsResin and HardenerSand and Cement
DurabilityHighly durable, suitable for drivewaysVaries, often less durable than epoxy
MethodMix two components and apply with a squeegeeBrush dry mix into gaps and optionally wet
Setting Time24-48 hoursDepends on conditions, often quicker
Surface PreparationClear gaps, dampen area, prevent seepage from edgesEnsure surface is dry, clear gaps
FinishSemi-fluid, settles naturallyMay require trowelling, can be crumbly
A table comparing epoxy jointing mortar to traditional brush in grout.

The practice of dry brushing-in for filling paving joints often results in subpar, crumbling mortar that allows weed growth. This occurs because without pre-wetting, the dry mix does not properly hydrate and bond. Irresponsible installers favour dry brushing as defects appear after they leave. Conscientious contractors can achieve better joints by packing dry mix into pre-filled, wet “butter” mortar. This provides moisture to initiate curing and hardening if the dry mix integrates well. However, care must be taken when later spraying water, as the cement-rich dry mix on the damp paver surface risks splashing and staining – the very issue dry brushing aims to avoid. Overall, combining wet mortar and tightly packed dry brushing can produce quality paving joints, but the technique demands care to avoid defects defeated its original purpose.

Motar bedding for paving with butter motar

What is the best mix for patio pointing?

The best mix for patio pointing typically involves combining 3 parts sand with 1 part cement. This mixture ensures both a cohesive and effective pointing solution for patios.

Should patio pointing be wet or dry mix?

For patio pointing, using a dry grout is often recommended, especially after laying an impermeable bedding layer. This method is particularly suitable for smooth pavers with consistent joints. However, it’s worth noting that unless a high-quality grout is used, dry grouting might be susceptible to issues like cracking and weed emergence.

What is the best mix for patio pointing?

The best mix for patio pointing typically involves combining 3 parts sand with 1 part cement. This mixture ensures both a cohesive and effective pointing solution for patios

Should patio pointing be wet or dry mix?

For patio pointing, using a dry grout is often recommended, especially after laying an impermeable bedding layer. This method is particularly suitable for smooth pavers with consistent joints. However, it’s worth noting that unless a high-quality grout is used, dry grouting might be susceptible to issues like cracking and weed emergence

Is sharp or building sand better for patio pointing?

For patio pointing, both building sand and sharp sand can be utilised. However, a slightly dry building sand or plastering sand is often preferred. Using sharp sand might sometimes yield a rougher finish, especially in dry grouting scenarios

Does sandstone paving need grouting?

Yes, sandstone paving requires grouting to fill the gaps between the slabs, ensuring stability, preventing weed growth, and achieving a finished look.

Does porcelain paving need grouting?

Yes, porcelain paving also requires grouting. Grouting not only enhances its appearance but also ensures the tiles are securely set and water doesn’t seep underneath.

Which is the best grout for sandstone paving?

For sandstone paving, a flexible and weather-resistant grout is ideal. It’s advisable to choose a grout that matches or complements the colour of the sandstone for a seamless finish

Which is the best grout for sandstone paving?

For sandstone paving, a flexible and weather-resistant grout is ideal. It’s advisable to choose a grout that matches or complements the colour of the sandstone for a seamless finish.

What do you mix with mortar for a patio?

When preparing mortar for a patio, it’s common to mix four measures of sand with one measure of cement. If the situation demands, a plasticiser can be added as per its specific instructions.

How much sand for block paving?

The average amount of sand you need per m2 of block paving is 3.3kg for 50mm block paving, 4.5kg per m2 for 60mm block paving, and 5.7kg per m2 80mm block paving.
 

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