Basement Waterproofing in Markham — Done Once, Done Right.
Whether your basement is leaking today or you want to waterproof it before finishing, we deliver permanent solutions: interior basement waterproofing, exterior basement waterproofing, foundation crack repair, and complete sump systems. Backed by a written workmanship warranty.
Signs you need basement waterproofing
- ✓Standing water or damp spots after heavy rain
- ✓White efflorescence on basement walls
- ✓Musty smell or visible mold
- ✓Peeling paint or bubbling drywall near the floor
- ✓Cracks in your foundation walls
- ✓Recurring sump pump cycling
Written Workmanship Warranty
Our work is backed for life — and the warranty stays with the home if you sell. That's a real selling feature when you list your Markham property.
Free, no-pressure inspection
A real local technician comes out, diagnoses the actual source, and gives you a written fixed-price quote. We'll tell you if you don't even need us yet.
Our process
Free inspection
We diagnose the actual source — not the symptoms.
Honest recommendation
Interior, exterior, or both. We'll explain why.
Fixed-price quote
Written, no surprises, no per-hour billing.
Permanent fix
Lifetime transferable warranty on every job.
Mold from a damp basement isn't just ugly — it's dangerous.
Hidden mold spores from a wet basement are linked to asthma attacks, chronic coughs, allergies and serious respiratory illness — especially in kids, seniors and anyone with a weak immune system. Every day you wait, it spreads further into your walls, insulation and air.
"Three inches of water in our finished basement on a Saturday morning. They were on site in two hours, found the wall crack the previous company had missed, and finished the full fix in two days. Bone dry through the next two storms."
Related services
Frequently Asked Questions
What does basement waterproofing actually include?+
It depends on the source of water. Interior basement waterproofing means a perimeter drainage channel cut into your floor and tied to a sump pit. Exterior basement waterproofing means excavating to the footing, applying a rubberized waterproofing membrane and dimple board, and replacing weeping tile. We diagnose first, then recommend the right approach.
Interior vs exterior — which is better?+
Exterior is the permanent fix because it stops water before it touches your foundation. Interior is faster, less invasive, and the right choice for floor-wall joint seepage or homes where excavation isn't possible. We're honest about which one your home actually needs.
How much does basement waterproofing cost in Markham?+
Foundation crack injection: $400–$900 per crack. Interior systems: $90–$130 per linear foot. Exterior systems: $300–$500 per linear foot. Most Markham jobs come in between $3,000 and $17,000 depending on scope. Use our cost calculator for a quick estimate.
Do you offer a warranty?+
Yes — a written workmanship warranty on exterior waterproofing and crack injection. It stays with the home if you sell.
How long does it take?+
Interior jobs: 1–3 days. Exterior single-wall jobs: 2–4 days. We protect your home and clean up daily.
Wet basement? Don't wait.
Every day water sits in your basement, mold spreads and your foundation weakens. Talk to a real Markham waterproofing expert today — free advice, no pressure.