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HardscapingInterlock Sanding & Joint
Restoration in Ottawa
If your interlock has weeds poking through, sunken joints full of debris, or ants colonizing between the pavers — the sand has failed. We remove it, clean the joints, and install fresh polymeric sand that locks everything in place.
The joint sand in your interlock is not permanent.
Every interlock driveway, patio, and walkway relies on the sand between the joints to stay stable. Over time, Ottawa's weather cycles — heavy rain, freeze-thaw, snowmelt — wash that sand out. UV breaks it down. The joints open up. And once the gaps are exposed, three things happen fast:
Weeds take root
Seeds land in the open joints, germinate, and send roots down into the base. Pulling them by hand leaves the root behind — they grow back thicker within weeks.
Ants build colonies
Empty joints are a highway for pavement ants. They excavate the bedding sand underneath the pavers and push it up through the joints, creating sinkholes that spread.
Pavers shift and sink
Without sand locking them together, individual pavers move independently under vehicle weight or foot traffic. Edges chip, surfaces become uneven, and water starts pooling.
The fix isn't just sweeping more sand on top — that sand sits on the surface and washes away in the next rain. The fix is removing what's failed, cleaning the joints, and installing fresh polymeric sand that activates with water and hardens into a flexible, permeable seal.
How we re-sand interlock so it stays put.
Strip the Old Sand
We use a power broom and compressed air to remove every trace of failed joint sand — down to the full depth of the paver. Surface sweeping alone leaves the bottom half of the joint filled with debris.
Deep Clean the Joints
We flush each joint with targeted water pressure that removes embedded dirt, moss, and ant debris without disturbing the bedding layer underneath. The joints are left clean and open for new sand.
Install Polymeric Sand
We sweep premium polymeric sand into every joint — not just on top. A plate compactor vibrates the sand down to full depth so there are no air pockets or voids. Excess is swept off the surface.
Activate & Lock
A controlled mist of water activates the polymers. The sand cures into a flexible, permeable seal that expands and contracts with Ottawa's seasons. Joints stay filled. Weeds and ants can't get through.
Polymeric sand vs. regular sand — why it matters.
Regular joint sand is just fine-grained silica. It sits loosely in the joints, washes out with every rain, and offers zero resistance to weeds or ants. If your original installer used regular sand, you've been fighting a losing battle since day one.
Polymeric sand contains polymer binders that activate on contact with water. Once cured, it forms a flexible, water-permeable seal that locks pavers together into one cohesive mat. Water drains through, but weeds, ants, and erosion can't break through. It flexes with freeze-thaw cycles instead of cracking. A proper polymeric sand installation typically lasts 8–12 years before needing a refresh.
Why Polymeric Sand Wins
Locks pavers together
Creates one unified surface that distributes weight evenly
Blocks weeds and ants
Hardens into a barrier that roots and insects can't penetrate
Resists washout
Stays in place through heavy rain, snowmelt, and power washing
Flexes with the seasons
Expands and contracts with Ottawa's 60°C annual temperature swing
Permeable to water
Drainage still works — water passes through, the sand stays
Is your interlock due for re-sanding?
Common questions about interlock sanding.
How often should interlock be re-sanded?+
Polymeric sand typically lasts 8–12 years before needing a refresh. Regular joint sand may need re-sanding every 2–3 years — which is why we only install polymeric. If you're seeing weeds, ants, or sunken joints, it's time regardless of how long it's been.
Can I just sweep new sand over the old sand?+
No — and this is the most common DIY mistake. New sand swept over old, debris-filled joints sits on the surface and washes out in the next rain. The old sand, moss, and debris block the new sand from reaching full depth. The joints look filled for about a week, then they're empty again. Proper re-sanding means stripping the old material first.
Will re-sanding fix pavers that have already shifted?+
Re-sanding locks pavers in their current position — it prevents further movement, but it won't re-level pavers that have already sunk. If your pavers are uneven, we assess whether spot re-levelling (removing affected pavers, re-compacting the base, and re-laying them) is needed before we re-sand the entire surface. We'll tell you what's needed during the free estimate.
How long does the polymeric sand take to cure?+
The initial set happens within 24 hours. Full cure takes 48–72 hours, depending on weather. We recommend keeping the surface dry for at least 24 hours after activation. After full cure, you can drive, park, and power wash normally — the sand is locked in permanently.
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Stop fighting weeds and ants every spring.
Free on-site assessment. We'll check your joints, tell you what's needed, and give you a clear scope of work before you commit.