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Canada
Basement waterproofing cost per linear foot
Waterproofing 30 m of basement wall from the inside, with new weeping tile, a membrane at the wall base and a sump pump, typically costs $10,500 before GST/HST, with most jobs between $8,200 and $13,700. The basic version is about $10,100; adding a battery backup pump and a backwater valve brings it to around $14,800. Exterior excavation with a membrane and new weeping tile can be priced in the calculator.
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mid-range, typicalCost by region
| Location | Basic | Mid-range | Premium |
|---|---|---|---|
| Quebec | $10,800 | $11,300 | $15,800 |
| Ontario | $10,300 | $10,800 | $14,900 |
| British Columbia | $10,200 | $10,600 | $14,800 |
| Alberta | $9,700 | $10,200 | $14,200 |
| Newfoundland and Labrador | $9,800 | $10,200 | $14,100 |
| Manitoba | $9,450 | $9,850 | $13,900 |
| Saskatchewan | $9,150 | $9,550 | $13,800 |
| Nova Scotia | $8,750 | $9,150 | $13,300 |
| New Brunswick | $8,600 | $9,000 | $12,800 |
What's included
Mid-range
- Building or plumbing permit where the municipality requires one
- Breaking out the floor along the treated walls
- New weeping tile in clear stone at the footing, with a dimple membrane at the wall base
- Concrete poured back over the trench
- Sump pit, pump, check valve and discharge line
- Downspout extensions to carry roof water away from the walls
What affects the cost
Interior or exterior
Interior waterproofing relieves water that reaches the wall and floor joint and pumps it away; it can be done in winter and leaves the yard alone. Exterior work digs down to the footing, often 2 m or more around a full basement, and restores the membrane and weeping tile from outside, which costs roughly twice as much or more.
Old weeping tile
Many older homes have clay weeping tile that is crushed, clogged with roots or connected to the sewer. A camera inspection before quoting shows whether the problem is the tile, the wall or both.
Finished basements
Finished walls, flooring and built-ins along the treated walls have to come out and be rebuilt, which can add substantially to an interior job.
Frost and access
Exterior work is limited by frozen ground and by driveways, decks, porches and neighbours' houses close to the wall. Tight side yards on city lots often push homeowners to the interior option.
Sump discharge
Where the pump discharges matters: onto the lawn, into a storm connection or away from a neighbour's property. Municipal rules differ and connections to sewers need a plumbing permit.
How to save
- Extend downspouts and correct the grading before anything else; it costs little and reduces the load on any system.
- Treat only the leaking walls if the rest stay dry through spring thaw.
- Ask your city about basement flooding subsidies before you sign, because most require approval or specific paperwork.
- Get quotes that separate the drain, sump pump, backup and backwater valve so you can compare and claim subsidies correctly.
Grants, tax and rules
Toronto basement flooding subsidy
Since 1 May 2026 the City of Toronto offers up to $6,650 per property for eligible work completed on or after 12 November 2025, each item at up to 80% of the invoice: up to $2,250 for a sump pump plus $300 for a battery backup, up to $1,600 per backwater valve (two maximum) and up to $400 to sever and cap the storm sewer connection. Contractors must hold a valid City of Toronto business licence, and a backwater valve needs a building permit and inspection.
Licensed trades and GST/HST
Plumbing and electrical work needs licensed trades and usually a permit. Our figures are before GST/HST (13% HST in Ontario, 5% GST in Alberta).
Frequently asked questions
How much does basement waterproofing cost in Canada?
Interior waterproofing with weeping tile and a sump pump along 30 m of wall costs around $10,500 before GST/HST. A basic job is about $10,100; with battery backup and a backwater valve it is around $14,800.
Is exterior waterproofing worth the extra cost?
It is the most complete fix because water never reaches the wall, but it costs far more and tears up landscaping. It makes sense when the foundation wall itself needs repair or the exterior is being dug up anyway.
Do I need a backwater valve?
If sewer backup is a risk in your area, a backwater valve protects the basement from water coming up through floor drains. In Toronto it qualifies for a subsidy of up to $1,600 per valve, with a building permit and inspection.
Can basement waterproofing be done in winter?
Interior work can, because it is done from inside the house. Exterior excavation is usually scheduled once the ground has thawed.
How long does it take?
An interior system for a typical basement takes a few days. Exterior work around a whole house can take one to two weeks depending on access and weather.
How this estimate is calculated
Work hours: 61.9 · Labour: $5,914 · Materials: $4,618
Sources: Job Bank wages (Employment and Social Development Canada); Regione Toscana, Prezzario dei Lavori 2026 (CC BY 4.0); ECB exchange rates; market check: About 100 linear ft of interior weeping tile with sump pump, before GST/HST. Wet Basement Resolutions Ontario 2026 guide (Mar 2026: interior $70-150/lf, $7,000-15,000; exterior $150-350/lf; sump $800-2,800, with battery backup $3,100-5,000; backwater valve $1,500-3,700); getabetterquote.com Ontario guide (interior $4,000-15,000, exterior $15,000-45,000+); TOR Contracting 2026.
Last reviewed September 26, 2026 · How we calculate costs · Editorial policy