Interlock sealing and cleaning in Markham

A lot of interlock that looks worn out isn’t. The pavers are often fine, just buried under years of dirt, moss and tire marks, with weeds where the joint sand used to be.

If nothing has sunk or cracked, interlock cleaning and new joint sand can bring a Markham driveway or patio back close to its original colour. Interlock sealing is an extra step you can add afterwards.

Cleaning suits interlock that has gone dark and blotchy, has weeds or moss in most joints, or is slippery in a shady corner. Empty joints and ant hills mean the sand has washed out and needs replacing.

Cleaning won’t fix pavers that have sunk or cracked. Our interlock repair page covers lifting and relaying those sections, and the two jobs are often done together.

1. We sweep the surface, move planters and furniture, and pull the weeds and grass out of the joints and along the edges.
2. We pressure wash with a wide spray at moderate pressure, which also flushes out the old joint sand. Then we work on oil drips and rust marks. Some come out completely and some only fade, and we’ll tell you which before we start.
3. Once the pavers and joints are fully dry, we sweep in new polymeric sand, compact it, blow every bit of loose sand off the surface and water it in with a gentle shower so it sets firm.

Techniseal’s polymeric sand instructions call for a dry surface, a day without rain and temperatures above freezing for at least 48 hours while it dries. More in our polymeric sand guide.

You can see this kind of job on our interlock restoration project: a patio beside a brick house with weeds and moss through a lot of its joints, pressure washed and re-sanded.

Only if you want what a sealer does. Unilock’s own guidance says its concrete pavers don’t need regular sealing.

People seal because it deepens the colour and makes stains easier to clean off. Water-based sealers can also help hold the joint sand in place.

A wet-look finish deepens the colour and adds some sheen, while a matte finish stays closer to the bare paver. Techniseal’s satin sealer sheet warns that its satin sealer makes the surface more slippery when wet, which matters on steps.

Mention it when you ask for a quote and we’ll talk it through. Our interlock sealing guide goes into the pros and cons.

Timing matters more than the product. The manufacturers give these waits:

Scroll sideways to see the whole table.

So on joints we’ve just re-sanded, sealing waits a few weeks. Labels differ, so check the one on your sealer.

We quote every job after seeing it. An open driveway goes faster than a patio of the same size with steps, borders and tight corners.

Deep moss and weeds in every joint take far longer than a surface that’s just grey. The more sand that comes out and goes back in, the longer it takes. Old polymeric sand has to be cleared out properly for the reasons in can you put new polymeric sand over old?

Stubborn stains need separate treatment, and any sunken or broken pavers are a repair on top of the cleaning.

Late spring through early fall. You can pressure wash on any mild day, but polymeric sand needs dry weather above freezing for at least 48 hours, and sealer needs about 10 °C or warmer.

Spring catches a surface at its worst after a winter of salt and sand. Early fall sends tight, fresh joints into winter.

Sweep or blow the surface off every few weeks so dirt and seeds don’t build up in the joints. Wipe up oil spills before they soak in, and point downspouts away from the pavers so water doesn’t wash out the sand.

Our guide on how to clean interlock covers what’s safe to use at home.

A small patio is a fair weekend job if you’re comfortable with a pressure washer. A narrow tip held too close can mark the pavers for good, as our guide to pressure washing decks, fences and interlock explains.

The joint sand is the hard part. We plan the sanding around the forecast, so it goes down on dry pavers with dry weather ahead.

We work across Markham and nearby, including Richmond Hill, Vaughan and Scarborough.

The easiest way to start is to text a few photos of your driveway, walkway or patio to (437) 684-2535 with your street or postal code. We’ll come and look and give you a free quote.

• Pavers that have gone grey, green or black, especially in shady spots
• Weeds, grass or moss growing in most of the joints
• Joints that look empty or sunken below the paver edges
• Ant hills and sand washing out onto the driveway after rain
• Slippery patches on steps or walkways in wet weather
• Oil drips, rust marks or tire marks that won't wash off with a hose