How to Seal Block Paving
Sealing block paving is a straightforward job – and with the right materials and a bit of elbow grease, it’ll keep your driveway or patio looking fantastic for years to come. With a bit of regular maintenance, the DIY sealing process protects your paved areas from the elements as well as preventing weed growth, making sure your paved areas stays looking immaculate. That’s why we’ve developed this helpful guide, based on the extensive experience of Marshalls’ paving experts, to help you through the process.
HOW TO SEAL BLOCK PAVING TO PREVENT WEEDS
To seal block paving you’ll need to clean, sand and seal the joints. First, scrub the paving and joints clean. Once dry, top up the joints with kiln-dried sand where required. Brush the sand into the joints before sweeping off the excess. Then apply sealer to protect the joints.
7 steps to sealing block paving:
Follow our simple 7 steps below to sealing your block paving.
- Clean the paving and joints using a pressure washer and a wire brush to remove as much loose dirt, debris and weeds as possible
- Leave the area to dry completely.
- Use a broom to remove any remaining loose dirt or weeds
- Refill the joints using kiln dried sand – our Jointing Sand is suitable for all paving types
- Brush off all excess sand above the joint
- Roll on the first coat of joint sealer
- Leave to dry, and spray or roll on the second coat of sealant
WHAT YOU’LL NEED TO SEAL BLOCK PAVING
Tools for sealing block paving
Sealing roller kit
Materials for sealing block paving
STEP BY STEP: SEALING BLOCK PAVING
TWO WEEKS BEFORE: THE BIG CLEAN
Using a pressure washer, give the surface and joints of your block paving a deep clean. It’s important to remove as much dirt, moss, lichen, debris and weeds as possible, as sealant is most effective in bone dry conditions.
LEAVE TO DRY
Leave the area to dry out for as long as you can. We recommend two weeks after pressure washing, so the spaces between blocks have had time to completely dry out. Check the dryness between pavers by raking out a few joints and testing the existing jointing sand up to 15mm deep.
Get rid of leftover weeds, dirt and debris, and make sure the weather looks dry for the next 24 hours so you can ensure the sealant works effectively and doesn’t trap any unwanted debris in the joints.
SAND THE JOINTS
Refill the joints between block pavers with jointing sand – any existing sand is likely to have washed away during cleaning. Brush a thin layer of jointing sand over the whole area and sweep into the joints. Work the broom back and forth to fill all joints.
SWEEP AWAY EXCESS SAND
Check the sand is of a consistent level no higher than the bottom of the v-joints. Sweep away the rest of the jointing sand, so you’re ready to seal the area.
PREPARING TO SEAL
Prime your rolling kit with the sealant, and begin to apply it to your paving. Make sure there’s always a good pool of sealant ahead of your roller so that you can apply enough as you go. Sealant coverage is usually poor on the first coat, so don’t worry if it takes some time to cover the whole area.
Important: Ensure you re-sand and seal on the same day. This is so the new sand stays secure in the paving joints.
SEALING THE PAVING – FIRST COAT
Before you start: Check the paving sealant application guidelines carefully. You should take appropriate safety measures as directed. Make sure the area is well-ventilated, and wear safety equipment such as gloves and goggles where required.
Roll on the first coat of paving sealant. Choose your roller carefully, as some react with the solvents in the sealant. Then, ensure that it’s applied thoroughly between the joints. When there is sufficient coverage, the colour of the jointing sand turns darker. You’ll typically cover about 4m2 per litre of sealer for the first coat. If you put more than this down, the mix may be too thick to begin the sealing process. Put down less and you won’t get full coverage. Leave to dry for 1-2 hours, depending on the weather.
SEALING THE PAVING – SECOND COAT
Use a sprayer filled with paving sealant to apply a second coat once the first coat is tack dry. Apply the second coat at right angles to the first, to increase coverage. You can cover more ground with the second coat – about 7m2 per litre. You can still use a roller for the second coat if you’d prefer, but either way it’s important to cover the entire surface.
LEAVE TO DRY (AGAIN)
Leave the freshly sealed pavers to dry for at least 24 hours to allow the sealant to fully take effect. In summer leave several hours before walking on it, or a day before driving on the surface. In winter, ensure you keep the area free from traffic for even longer.
CAN I SEAL OVER A TARMAC DRIVEWAY?
When sealing over a tarmac driveway the only thing that’s different is there’s nothing to sand or joint. Again, make sure you adequately cover the area in sealer for every coat.
First, pressure wash the entire driveway so it’s as clean as possible. Then wait for it to dry before adding the sealant, in the same way you would with paving.