Paver Patio FAQ: 10 Common Interlock Paver Questions Answered

Interlock pavers are the most popular hardscaping choice for Montreal homeowners, but they come with plenty of questions. Here are clear answers to the ones we hear most often.

How long do interlock pavers last?

Interlock pavers typically last 25 to 50 years when properly installed with an adequate base. Most major manufacturers like Techo-Bloc, Permacon, and Rinox offer lifetime limited warranties on their products. The pavers themselves are extremely durable and resist cracking even in Quebec's harsh freeze-thaw cycles. The key to longevity is the base preparation underneath, as a well-compacted gravel base prevents shifting and settling that would otherwise shorten the life of any paver installation.

Can pavers be installed over existing concrete?

Yes, pavers can be installed over existing concrete in some situations, but it's not always recommended. The concrete must be in good structural condition without major cracks or heaving. A thin layer of sand is placed over the concrete before laying the pavers, and proper edge restraints are needed. The main concern is drainage, because water needs somewhere to go, and concrete underneath can trap moisture. In Quebec, this approach carries extra risk because freeze-thaw cycles can cause the concrete slab to heave, which pushes the pavers out of alignment.

Do pavers need sealing?

Sealing pavers is optional but offers real benefits. A good sealer protects against staining from oil, food, and organic matter, enhances the colour of the pavers, and helps lock in the joint sand. Sealed pavers are also easier to clean. Most professionals recommend sealing about a year after installation, once the pavers have fully settled and any efflorescence (the white powdery residue that can appear on new concrete products) has worked its way out. Resealing every three to five years keeps the protection fresh.

What is polymeric sand and why is it used?

Polymeric sand is a specially engineered joint fill made of fine sand mixed with binding agents that harden when activated with water. It's used to fill the gaps between pavers, and once it sets, it locks the pavers in place, prevents weed growth, and stops insects from burrowing up between joints. Regular sand washes out over time and allows weeds to take root, but polymeric sand stays firm. Proper application is important because too much water or applying in the wrong conditions can cause hazing on the paver surface.

How do you prevent weeds between pavers?

The most effective way to prevent weeds is using polymeric sand in the joints, as it creates a hardened barrier that weeds can't push through. Proper installation with a geotextile fabric underneath the base also helps by preventing weed growth from below. If weeds do appear, they're usually growing in debris that's accumulated on top of the joints rather than coming up from underneath. Regular sweeping, occasional power washing, and re-applying polymeric sand when it wears down will keep your patio virtually weed-free.

What base depth do pavers need in cold climates?

In Quebec's cold climate, pavers need a minimum base depth of 12 inches for pedestrian areas like patios and walkways, and 18 inches or more for driveways that support vehicle traffic. This is deeper than what's required in milder climates because the base needs to extend below the frost line to prevent heaving. The base consists of compacted crushed stone (typically 0-3/4 inch gravel) topped with a levelling layer of stone dust or concrete sand. Skimping on base depth is the number one reason paver installations fail in Quebec.

Are pavers slippery when wet?

Most modern pavers have textured surfaces designed to provide good traction, even when wet. They're generally less slippery than smooth poured concrete or natural stone like polished granite. Some paver styles are specifically rated for slip resistance. If traction is a concern, look for pavers with a tumbled or textured finish rather than a smooth, polished one. In winter, pavers handle salt and ice melt products well, and their textured surface provides better grip than smooth alternatives.

Can you repair individual pavers without redoing the whole patio?

Yes, and this is one of the biggest advantages of interlock pavers over poured concrete. Individual pavers can be lifted out and replaced without affecting the surrounding surface. This makes repairs from settling, staining, or damage straightforward and cost-effective. A professional can remove the damaged pavers, fix the base underneath if needed, and drop in replacement pavers that match the originals. It's a good idea to keep a small supply of extra pavers from your original installation for this purpose, as colours and textures can vary slightly between production batches.

What paver patterns are best for driveways vs patios?

For driveways, herringbone patterns (either 45-degree or 90-degree) are strongly recommended because they interlock tightly and distribute vehicle weight evenly, preventing pavers from shifting under tire traffic. Running bond and basket weave patterns work well for patios and walkways where there's only foot traffic. For a premium look on patios, random patterns using multiple paver sizes create visual interest. The choice also depends on the paver shape, as some products are specifically designed for certain laying patterns.

How soon can you walk on newly installed pavers?

You can walk on newly installed pavers as soon as the polymeric sand has been applied and watered, which is typically the same day the installation is completed. However, you should avoid heavy use or placing furniture on the patio for at least 24 hours to let the polymeric sand fully cure. For driveways, most installers recommend waiting 48 to 72 hours before driving on the surface. Avoid getting the area wet again for at least 24 hours after the initial polymeric sand activation, as additional water can wash out the sand before it sets.

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Have more questions about interlock pavers? Call us at 514-900-3867 or send photos of your project for a free estimate. Montreal Paysagement Pro specializes in paver installation for Montreal homeowners.