Basement Waterproofing Cost Guide Toronto and Surrounding Area (2026)

In 2026, the average cost of basement waterproofing in Toronto ranges from $70 to $250+ per linear foot. Interior waterproofing systems typically cost between $70 and $150 per linear foot, while professional exterior waterproofing ranges from $150 to $250+ per linear foot. Total project costs for a standard GTA home usually fall between $5,000 and $20,000+ depending on excavation depth and foundation accessibility.

5 Factors That Influence Your Waterproofing Cost

1. Foundation Depth: Excavating a 9ft foundation requires more shoring and labor than a standard 6ft footer.

2. Accessibility: Hand-digging in narrow downtown Toronto alleys increases labor costs compared to machine excavation.

3. Soil Composition: Toronto’s “heavy clay” (common in Etobicoke and Mississauga) is harder to dig and requires more clear-stone backfill.

4. Hardscaping: Removing and restoring concrete patios, interlock, or decks adds to the total estimate.

5. Subsidies: Homeowners can reduce costs by up to $6,650 through the City of Toronto Basement Flooding Protection Subsidy.

Basement waterproofing is commonly priced as a waterproofing price per linear foot. Interior waterproofing cost per linear foot is often lower because it typically avoids excavation. Exterior waterproofing cost per linear foot is usually higher because it involves more labour for digging, wall prep, waterproof membranes, drainage improvements, and restoration.

How to Get a Basement Waterproofing Quote

To get a basement waterproofing quote, you should request an on-site inspection from a licensed contractor. An accurate estimate requires a physical assessment of your foundation depth, soil type (clay vs. sand), and external obstructions like decks or AC units. Professional quotes in the GTA typically include an itemized breakdown of labor, premium materials, and a transferable lifetime warranty.

Our 3-Step Precision Quote Process

1. On-Site Inspection: We visit your property to measure linear footage and evaluate excavation access.

2. Diagnostic Audit: We identify “cost-drivers” like narrow side-yards or the need for specialized shoring.

3. Digital Proposal: Within 24 hours, you receive a fixed-price quote covering all permits, debris disposal, and materials.

What Influences the Cost of Waterproofing?

The cost of basement waterproofing is influenced primarily by the method of repair (Interior vs. Exterior), the depth of the foundation, and property accessibility. In 2026, exterior waterproofing prices in Toronto are also impacted by soil composition (heavy clay increases labor) and the need to remove or restore hardscaping like interlock or concrete patios.

• Foundation Depth: Deeper footings require more excavation and shoring.
• Access Constraints: Manual digging in tight alleys costs more than machine excavation.
• Water Table: High water tables may require additional drainage or high-capacity sump pumps.

SELECT YOUR JOB TYPE:

Exterior Waterproofing

Number of Linear Feet (Required):

Number of Window Wells (Required):

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The exterior method involves excavating your walls down to the base(footings) of your home. In order quote with this method, you would need to measure the linear footage of the exterior wall. That is pretty much it. Although you need to keep in mind that additional costs may be applied depending on obstructions associated with the dig. Factors such as window wells, shrubs and trees, concrete, interlock, larger than average depths to the base of house (average depth to base of house is 5’-6’), soil composition(clay) and if the area that needs to excavated can support and has room for an excavator. If your foundation is cinderblock, it is necessary that that the entire wall is addressed because the walls are

Interior Waterproofing

Number of Linear Feet (Required):

Number of Interior Sumps (Required):

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The interior method involves breaking the concrete along the wall being treated and creating a channel for new weeping tiles. This channel is connected to proper drainage that will discharge the water away from the home. If you have a drain near the problem area, the channel can be connected along the wall and attached to the drain. In this case you would measure the problem wall and the distance to the drain for your linear footage. If there is not a drain near the wall your other option is to connect to a sump pump. This method will allow the channel to be connected to a newly installed sump pump which would expel the water out and away from your home. In this case you would measure the linear footage of the wall to where you would hypothetically place the sump pump. Remember a sump pump needs to be connected to an electrical outlet in order to operate, or a power outlet needs to be installed.

Crack injection Sealing

Number of Cracks:

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Crack injections are only possible when the foundation is poured concrete. If you have a block foundation it is not possible because the blocks are hollow. If you have a brick or fieldstone foundation there are air gaps in the concrete and mortar that injections will not completely seal. Cracks can run vertically or horizontally along the wall or floor and the price is based on a 7’-8’ length with the walls completely exposed.

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Use the Basement Waterproofing Cost Calculator above for a planning estimate, then request an inspection for a written quote.

What This Basement Waterproofing Cost Calculator Includes

This calculator is intended for basement waterproofing work such as:

• Interior waterproofing (interior drainage / weeping tile / wall membrane and concrete)
• Exterior waterproofing (excavation / sealing foundation walls outside and backfilling)

If your issue is a single, isolated poured-concrete crack that leaks only at one spot throught a basement wall crack, a crack injection is often priced per crack rather than per linear foot. If that describes your issue, use our crack injection cost page for a more accurate planning estimate.

That’s why the best way to get a reliable waterproofing estimate is to combine:

1. a planning estimate (calculator + typical price-per-foot ranges)
2. a site inspection (to confirm method, footage, access, and drainage requirements)

Interior vs Exterior Basement Waterproofing Cost

Interior basement waterproofing may be the best fit when:

• Water shows up along the floor edge (cove joint) or at multiple points inside
• Exterior excavation is difficult due to limited access or hardscaping
• You want a solution that manages groundwater pressure and routes water safely away

Exterior basement waterproofing may be the best fit when:

• You need to seal the foundation wall from the outside at the source
• Leaks recur in the same area and exterior access is possible
• Exterior cracks or wall conditions require outside repair and membrane protection

Best practice: Don’t compare “per-foot” prices until you confirm the scope is the same (depth, drainage plan, and what restoration is included).

What Affects Basement Waterproofing Cost the Most?

Whether you’re using an online basement waterproofing cost calculator or comparing quotes, these are the biggest cost drivers in Toronto/GTA and Southern Ontario homes:

1. Total linear footage
   One leaking wall is very different from multiple walls or a longer run that needs protection.
2. Method (interior vs exterior)
   Interior drainage work and exterior excavation work are different scopes with different labour and materials.
3. Foundation depth (especially for exterior work)
   Deeper basements can increase excavation time and safety requirements.
4. Access around the home
   Narrow side yards and tight access can require hand excavation or special planning.
5. Obstructions and site conditions
   Decks, porches, interlock, concrete walkways, landscaping, stairs, and utilities can add complexity.
6. Drainage requirements
   Sump pump needs, discharge routing, tie-ins, and water management design affect scope.
7. Finished vs unfinished basement access
   Finished walls/floors can require careful opening and patching depending on the solution.

If you want a waterproofing estimate that’s actually comparable between contractors, ask each company to confirm: footage, depth assumptions, drainage plan, and what restoration is included vs excluded.

Most Toronto homeowners ask: “Is it better to waterproof from the inside or the outside?” The answer depends on your budget, your foundation type, and where the water is entering.

When to Choose Exterior: You have damp spots high on walls, visible exterior cracks, or are renovating landscaping. When to Choose Interior: Water seeps up through the floor/cove joint, or you have tight space between houses (narrow gangways).

When to Choose Exterior: You have damp spots high on walls, visible exterior cracks, or are renovating landscaping. When to Choose Interior: Water seeps up through the floor/cove joint, or you have tight space between houses (narrow gangways).

Common Signs Your Basement Needs Waterproofing

Before you see a flood, your home usually gives you warning signs:

Efflorescence (White Powder):

• White, chalky powder on walls is mineral deposit left by evaporating water. It is the #1 sign of slow seepage.

The “Cove Joint” Leak:

Water appearing where the wall meets the floor usually indicates hydrostatic pressure building up under your house.

• Horizontal Cracks: Vertical cracks are often settling, but horizontal cracks in block walls can indicate soil pressure pushing the wall in. Call us immediately if you see these.

Winter Waterproofing: Can You Do It in Freezing Weather?

• Interior Waterproofing (Year-Round): Since we work from the inside, we can install weeping tiles and sump pumps in January without issue.

• Exterior Waterproofing (Seasonal): Excavating frozen ground is difficult and costly. Exterior work is best scheduled for Spring-Autumn, though emergency fixes are possible with heating equipment.

• Winter Tip: Keep window wells clear of snow to prevent melting water from rising above the window frame.

2026 Local Rebates & Subsidies

We help homeowners across our service area apply for municipal flood prevention subsidies.

• • Toronto: Up to $6,650 (Basement Flooding Protection Subsidy).
  • Peel Region: Up to $700 – $1,500 (Sanitary Backwater Valve Rebate).
  • Halton Region: Up to $2,725 (Enhanced Basement Flooding Prevention).
  • Hamilton: Up to $2,000 (Protective Plumbing Program).
    

    City of Toronto Basement Flooding Protection Subsidy (2026 Update)

    ⚠️ IMPORTANT 2026 ALERT: As of May 1, 2026, the City of Toronto is increasing the maximum subsidy from $3,400 to $6,650.

    • If your basement is NOT currently flooding: It may be financially smart to schedule your installation for after May 1st to claim the higher rebate amounts, including new coverage for battery backups.

    • If you have an emergency: Do not wait. The current $3,400 rebate is still active.

    What is Covered? (The 2026 Breakdown)

    The program covers 80% of the invoiced cost up to the following maximums. Note the difference between the “Current” and “New” limits arriving in May.

Who is Eligible?

To qualify, you must meet all of the following criteria:

• You own a single-family, duplex, triplex, or fourplex home in the City of Toronto.
• The property does not have outstanding taxes or debts to the City.
• The downspouts have been disconnected from the City sewer system (or you have an exemption).
• Crucial: You must hire a contractor with a valid City of Toronto Business License (specifically for plumbing/drain work). A general handyman license does not qualify.
• Step-by-Step: How to Claim Your Money

Step 1: Hire a Licensed Contractor Do not buy the pump yourself at Home Depot. The City requires the invoice to come from a licensed professional. Ask your contractor: “Can you show me your City of Toronto business license number?”

Step 2: Get the Building Permit (MANDATORY) Your contractor must apply for a building permit for a Backwater Valve installation.

• Warning: If you install the valve without a permit, the City will deny your rebate application.

Step 3: Installation & Inspection Once the work is done, the City of Toronto Building Inspector must view the installation. They will verify it meets code. You will need this “passed inspection” report for the application.

Step 4: Pay & Submit You must pay the contractor in full first. Then, submit the following to the City (online or mail):

1. 1. 1. The “Basement Flooding Protection Subsidy” Application Form.

      2. The original invoice marked “Paid in Full.”

      3. The finalized Building Permit inspection report.

How to Measure Linear Footage for a Waterproofing Estimate

If you want to get the most accurate planning range from this basement waterproofing cost calculator, use these steps:

1. Identify the problem area
   Which wall(s) show water, dampness, staining, or seepage?
2. Measure the wall length
   Measure along the inside wall where the water appears (or the outside wall if accessible).
3. Add sections together
   If more than one wall leaks, add the lengths to get total linear footage.
4. Note access and obstructions
   For exterior work, decks, concrete, stairs, and narrow side yards can impact scope and cost.

If you’re not sure where water is entering, an inspection is the fastest way to confirm the true entry point and avoid paying for the wrong solution.

Basement Waterproofing Cost FAQ (Toronto & GTA)

What affects waterproofing cost the most?

The biggest drivers are method, linear footage, depth (for exterior work), access restrictions, obstructions, and drainage requirements. Two quotes with the same “per foot” number can be very different if they include different drainage plans or restoration.

Is interior waterproofing cheaper than exterior waterproofing?
Often, yes—interior waterproofing can be lower cost because it usually avoids excavation. However, the right solution depends on where the water is entering and what will solve it long-term. An inspection confirms the best method.

What does “price per linear foot” actually mean?

It typically refers to the length of wall/joint being protected. For interior systems it can relate to the drainage run inside the basement. For exterior systems it relates to the length of excavation and outside wall treatment. Always confirm what’s included in that per-foot scope.

Do finished basements cost more to waterproof?

They can. Access to the area that needs work matters. Some waterproofing methods require opening finished walls or floors in specific areas, and then patching/finishing afterward.

Can you give a waterproofing estimate without an inspection?

We can provide a planning estimate using the method and linear footage, but the final price requires confirming entry point, depth, access, and drainage requirements. That’s why the calculator is a starting point and the inspection is the confirmation step.

Is crack injection included in basement waterproofing cost per foot?

Crack injection is usually priced per crack (not per linear foot). If water enters through one isolated poured-concrete crack, crack injection may be the right estimator. If water is coming from the cove joint or broader seepage, linear-foot waterproofing methods are more common.

Get a Basement Waterproofing Estimate (Toronto & GTA and Souther Ontario)

Use the basement waterproofing cost calculator to build a planning range, then book a free inspection to confirm:

• the true entry point (cove joint, wall seepage, crack, drainage issue)
• the best method (interior vs exterior)
• total linear footage and depth assumptions
• what’s included (drainage plan, sump/discharge routing, restoration)

Request an inspection: 1-800-277-5411 or Contact Us

Service area: Toronto, the GTA and Southern Ontario

Rated 4.9/5 Stars based on 10,000+ Ontario projects.

All of our basement waterproofing solutions come with a full lifetime transferable warranty.