Keep your block paving looking fantastic all year round with a bit of DIY sealing. Sealing helps protect against the elements, limits weed growth, and keeps colours looking fresh. Below, we cover best practices and a step-by-step for sealing block paving.
Before you start: conditions & safety
- Dry window: Aim for 48 hours of dry weather before and after sealing. Ideal air/stone temperature is roughly 10–25 °C.
- Clean, sound surface: Strip dirt, algae, old loose sand, and any flaking sealer. Make small repairs now (sunken blocks, broken edges, failed joints).
- PPE: Gloves and eye protection are a must. If you’re pressure washing or blowing joints out, add hearing protection and a dust mask.
- Compatibility: If you’ve used resin or polymeric jointing in the past, check the sealer label for compatibility first.
Try your chosen sealer on a small, inconspicuous area and leave for 24 hours to check colour change, sheen, and drying before doing the whole drive.
How to seal your block paving to prevent weed growth
To be able to seal your block paving, it’s essential to clean, sand, and then seal the joints. Clean the paving and joints by scrubbing them; once fully dry, place kiln-dried sand in the joints. Brush off excess sand and then apply the sealer to lock the joints and protect the surface.
Below you can find our simple guide on how to seal your block paving:
Materials and tools required
- Joint Sealer
- Kiln-Dried Sand, Jointing Sand, or Marshalls Weatherpoint
- Pressure Washer
- Sealer Roller Kit (roller tray + medium-nap roller)
- Broom
- Disposable gloves (to keep hands clean)
Mask edges if needed and seal in 1–2 m² zones to keep a “wet edge” and avoid lap lines.
Step 1
Deep clean your paving and the joints! This can be done using a pressure washer and a brush to remove as much dirt, debris and most importantly those annoying weeds!
The reason why you should do a deep clean is to ensure that any debris, dirt and weeds have been removed as possible as this will allow the sealant to be its most effective when applied.
Use a 25–40° fan nozzle and keep the lance ~200–300 mm off the surface to avoid gouging joints or lifting blocks.
Step 2
Once you’ve cleaned your paving and joints with the pressure washer, allow the area to dry. We recommend you do a pressure washer clean around two weeks before planning to seal your block paving.
Joints must be bone dry before re-sanding and sealing. If in doubt, tape a small clear bag to the surface for an hour; condensation means wait longer.
Step 3
Brush away any remaining dirt and weed – this is super important as you don’t want any kind of debris left in the joints and underneath the sealant. This will also limit the effectiveness of the sealant, so make sure you can remove as much as possible or all.
Step 4
Using kiln-dried sand or jointing sand refill the joints as the existing sand would have been washed away while cleaning.
Top tip – take a small amount of sand and layer on the joint and using your broom, brush over to ensure the sand is swept in.
Also, it’s important that if you’re going to be re-sanding, then you must seal on the same day to ensure the new sand is locked under the paving joints and is secure.
Use kiln-dried sand for free-flowing fill. Damp or general sand bridges in the joints and won’t compact properly.
Step 5
Brush away the excess sand and make sure it is a consistent level. It should be no higher than the bottom of the v-joints.
At this stage, you’re ready to start sealing your block paving.
Step 6
Begin to roll on the first coat of the joint sealer using your roller kit. You may find on the first coat the coverage of the sealant isn’t as strong, but on your second coat it will be fine. Do take your time, as this is a long process to cover the whole area.
Let the first coat dry for approximately 1–2 hours (weather dependent).
Thin, even coats penetrate and cure better than one heavy coat. Keep a wet edge and back-roll to avoid puddling.
Step 7
After allowing the first coat to dry, proceed onto rolling the second coat of the joint sealant. This will help increase coverage.
Step 8
Let the second coat dry for around 24 hours to see its full effect.
Foot traffic after ~24 hours; keep vehicles off for 48–72 hours (check your sealer label). Avoid sealing in direct, hot sun to prevent flash-drying.
Aftercare & maintenance
- Regular sweep & rinse: Brush debris and rinse a few times each season to prevent organic build-up.
- Top up joints: If joints settle, top up kiln-dried sand before weeds take hold.
- Reseal timing: Most driveways benefit from resealing every 2–3 years, patios every 3–4 years (usage and exposure dependent).
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