Structural · Cost Guide
How Much Does Waterproofing Cost in Ontario?
Waterproofing costs in Ontario range from $5,000 – $12,000 per wall. Prices vary by scope, city, and site conditions.
$5,000+
Starting price
3-14 days
Timeline
10%
Recommended contingency
Waterproofing Cost Breakdown
| Scope | Low | High | Unit | Labour | Material |
|---|---|---|---|---|---|
| Exterior waterproofing (one wall, 20-30 ft) | $5,000 | $12,000 | per wall | 65% | 35% |
| Full-perimeter exterior waterproofing | $18,000 | $40,000 | per project | 60% | 40% |
| Interior drain tile + sump pump | $5,000 | $10,000 | per project | 55% | 45% |
| Crack injection (epoxy/polyurethane) | $500 | $1,500 | per crack | 70% | 30% |
| Sump pump replacement | $800 | $2,000 | per unit | 50% | 50% |
Price Ranges at a Glance
Exterior waterproofing (one wall, 20-30 ft)
Full-perimeter exterior waterproofing
Interior drain tile + sump pump
Crack injection (epoxy/polyurethane)
Sump pump replacement
What's Included vs Not Included
Typically Included
- Excavation to footing depth
- Foundation cleaning and crack repair
- Rubberized waterproofing membrane
- Weeping tile with filter fabric
- Dimpled drainage board
- Gravel backfill near foundation
- Basic grading and surface drainage
Not Included (Extra Cost)
- Landscaping restoration (sod, gardens, walkways)
- Driveway repair if excavation crosses it
- Interior finishing (drywall, paint) after repair
- Mold remediation if existing mold found
- Tree removal near foundation
- Downspout extensions and gutter repairs
Waterproofing Cost by City
Prices adjusted for local labour rates and material costs across 15 GTA cities.
| City | Low | High | vs Toronto | Details |
|---|---|---|---|---|
Toronto City of Toronto | $5,000 | $12,000 | 0% | View |
Mississauga Peel Region | $4,738 | $11,370 | -5% | View |
Brampton Peel Region | $4,605 | $11,052 | -8% | View |
Vaughan York Region | $4,853 | $11,646 | -3% | View |
Markham York Region | $4,820 | $11,568 | -3% | View |
Richmond Hill York Region | $4,803 | $11,526 | -4% | View |
Aurora York Region | $4,688 | $11,250 | -6% | View |
Oakville Halton Region | $5,098 | $12,234 | +2% | View |
Burlington Halton Region | $4,785 | $11,484 | -4% | View |
Milton Halton Region | $4,605 | $11,052 | -8% | View |
Ajax Durham Region | $4,523 | $10,854 | -9% | View |
Pickering Durham Region | $4,605 | $11,052 | -8% | View |
Oshawa Durham Region | $4,408 | $10,578 | -12% | View |
Whitby Durham Region | $4,490 | $10,776 | -10% | View |
Hamilton City of Hamilton | $4,473 | $10,734 | -10% | View |
Permit & Engineering Costs
Building Permit (sometimes required)
City of Toronto or local municipality
Most municipalities do NOT require a permit for exterior waterproofing (repair work), but some require permits if you're excavating deeper than 4 feet or within 3 feet of a property line. Check with your local building department.
$0-$500
Plumbing Permit (if installing sump pump)
City plumbing inspector
Required if you're tying the sump discharge into the storm sewer or municipal drainage system. Not required if you're discharging to the surface (lawn or driveway).
$150-$300
Ontario One Call Utility Locate
Ontario One Call
Locates underground gas, water, electrical, and telecom lines. Hitting a gas line during excavation can cause explosions; hitting a water main floods the excavation and costs $10,000+ in emergency repairs.
Free (mandatory 5 days before digging)
Money-Saving Tips
Fix grading and extend downspouts first — $1,000-$3,000 in drainage work solves 80% of moisture problems.
Combine waterproofing with underpinning or foundation repair to share excavation costs.
Exterior waterproofing costs 2-3x more than interior but is 5-10x more effective.
Ask for Big-O pipe with filter fabric — contractors who skip the fabric save $100 and cost you $15,000 in a decade.
Battery backup sump pump ($600-$1,200) prevents flooding during power outages.
Related Cost Guides
Waterproofing Cost FAQs
Is interior waterproofing good enough, or do I need exterior?
Interior systems (drain tile + sump pump) manage water AFTER it enters the foundation. They don't stop the water, they just collect it and pump it out. This keeps your basement floor dry, but the foundation walls stay wet. Over 10-20 years, that moisture accelerates freeze-thaw damage (concrete spalling), rebar corrosion, and efflorescence. Exterior waterproofing stops water before it touches the foundation. If you're planning to stay in the house long-term, exterior is the better investment. If you're selling soon or on a tight budget, interior systems are acceptable as a short-term fix.
How long does a waterproofing membrane last?
Rubberized membranes (Blueskin, Bituthene) have a lifespan of 30-50 years if installed correctly. Liquid-applied membranes (Tremco, SealBoss) last 20-30 years. The failure mode is usually physical damage (roots, settlement, or poor backfill technique) rather than material degradation. Dampproofing tar lasts 10-15 years before it cracks and peels — that's why you see so many 1970s-1990s homes with basement water issues.
Can I waterproof just one wall, or do I need the whole perimeter?
You can waterproof one wall, but water will find the path of least resistance. If the north wall is sealed but the south wall isn't, water flows around the perimeter and enters through the south wall. It's like patching one hole in a boat — the water just comes in somewhere else. That said, if you KNOW the leak is isolated to one wall (e.g., a crack on the east side that only leaks during east-wind rainstorms), waterproofing that wall can work. Most contractors recommend full-perimeter work to eliminate all entry points.
What's the difference between Big-O pipe and rigid PVC weeping tile?
Big-O is flexible corrugated pipe made from polyethylene. It's easy to install around corners and can handle minor soil settlement without cracking. The downside: the corrugations can trap silt, and the pipe can sag if the gravel settles. Rigid PVC pipe (Schedule 40 with drilled holes) is stronger and maintains slope better, but it requires couplings at corners and is more prone to cracking if the soil shifts. For most residential jobs, Big-O wrapped in filter fabric is the standard. PVC is used in commercial applications or where long-term slope maintenance is critical.
Why does my basement still smell musty after waterproofing?
Musty smell is mold, and mold needs three things: moisture, organic material (drywall, wood, carpet), and warmth. Waterproofing stops bulk water (puddles, wet floors), but it doesn't stop vapor transmission through the concrete or eliminate existing mold colonies. You need to: (1) run a dehumidifier to keep relative humidity below 60%, (2) remove any moldy materials (drywall, carpet, insulation), and (3) seal the basement floor with a vapor barrier paint or epoxy coating. Some basements also have moisture coming from interior sources — unvented dryers, bathroom exhaust, or plumbing leaks.
Shop Supplies for This Project
Browse tools, materials, and safety gear for your waterproofing project — curated for Canadian renovations.
Ready to Get Waterproofing Pricing?
Get instant pricing with our free Price Check tool, or browse vetted waterproofing contractors in your area.