# Basement Waterproofing Toronto | Pro Excavation Toronto

> Interior and exterior basement waterproofing in Toronto: membrane, weeping tile, sump and backwater valves, paired with underpinning. $8K-$40K, quote in 24h.

URL: https://proexcavationtoronto.ca/basement-waterproofing/

![Exterior basement waterproofing on a Toronto house with membrane and dimple board on the foundation wall](/images/misc/exterior-basement-waterproofing-on-a-toronto-house.webp)

24-Hour Written Quote

# Basement Waterproofing Toronto, ON | Interior + Exterior + Weeping Tile

Last updated: October 13, 2026

Pro Excavation Toronto

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 provides underpinning, basement excavation and demolition throughout Toronto, backed by 22+ years combined Toronto excavation and underpinning experience. We stop basement leaks at the source by excavating outside the foundation, cleaning and parging the wall, then installing an elastomeric membrane, dimple drainage board, new weeping tile and clear stone before backfill.

Where the side yard is too narrow to dig, we install an interior drain and sump system instead, and our P.Eng tells you honestly which approach suits your foundation. We also install backwater valves and sump pumps that may qualify for the City of Toronto Basement Flooding Protection Subsidy.

$8K-$40K per basement

-   Exterior Membrane
-   New Weeping Tile
-   Subsidy Eligible Work
-   $5M liability + WSIB + Tarion

Fix My Leaking Basement

[#quote →](#quote)

 

Call (647) 277-2002

[tel:+16472772002 →](tel:+16472772002)

22+

Years Combined

100%

P.Eng Stamped

24h

Written Quote

Thanks, we have your request.

We will call within 24 hours (business hours) to book your site visit. For a water or sewer emergency call (647) 277-2002 now.

-   22+
    
    Years Combined
    
-   100%
    
    P.Eng Stamped
    
-   24h
    
    Written Quote
    
-   $5M
    
    Liability + WSIB
    
-   4h
    
    Emergency On-Site
    

Quick Answers

## Basement Waterproofing in Toronto, Explained

Basement waterproofing keeps groundwater and surface water out of a basement. Exterior waterproofing seals the outside of the foundation wall with a membrane and drainage board and replaces the weeping tile at the footing. Interior waterproofing manages water that gets in, with a perimeter drain and a sump. In Toronto, old clay weeping tile, high water tables near the lake and combined sewers make both common.

### What basement waterproofing costs in Toronto

Most Toronto waterproofing projects cost $8K to $40K. An interior drain and sump along one or two walls often runs $8K to $15K. Exterior membrane on one side of a house is commonly $12K to $22K. A full exterior perimeter with new weeping tile is usually $25K to $40K. Our Etobicoke project, a dig-out plus exterior waterproofing on a high water table lot, was $45K.

### The rules and programs in Toronto

Exterior waterproofing needs Ontario One Call locates before digging. Connecting weeping tile or a sump to the City's system must follow the Toronto Sewer Use By-law, and downspouts are generally disconnected from the sewer. Backwater valves and sump pumps may qualify for the City of Toronto Basement Flooding Protection Subsidy, which requires a plumbing permit and specific installation details.

### Who does basement waterproofing in Toronto

Hire a contractor who diagnoses the source of water before recommending a system, owns excavation equipment for exterior work, carries WSIB and liability insurance and gives a written warranty. Pro Excavation Toronto waterproofs as a stand-alone service and as part of underpinning and dig-outs.

What We Do

## What Is Included in Our Waterproofing Work?

Exterior membrane and weeping tile, interior drainage and sumps, built into underpinning projects or as stand-alone repairs.

-   Exterior excavation, membrane and dimple board
-   Weeping tile replacement with clear stone
-   Interior drain and sump systems for narrow lots
-   Backwater valve and sump pump installation
-   Waterproofing tie-in during underpinning

**Includes:** Excavation, membrane, drainage, backfill. **Timeline:** 3-10 working days.

![New perforated weeping tile laid in clear stone at the footing](/images/content/new-perforated-weeping-tile-laid-in-clear-stone-at.webp)

Etobicoke basement dig and exterior waterproofing on a high-water-table lot, dry through spring melt ($45K).

## What Is Basement Waterproofing?

Basement waterproofing is any system that keeps water out of a basement or carries it away before it causes damage. In Toronto the problem usually comes from three places: groundwater pushing against the foundation because the old weeping tile has failed, surface water from poor grading and downspouts, and sewer backups during heavy storms. Each needs a different fix, so we start by finding where the water is actually coming from.

Because we are an 

excavation and underpinning contractor

[/ →](/)

 first, exterior waterproofing is natural work for us. Digging down to a footing along a narrow side yard, protecting gas lines and supporting the wall while it is exposed is what we do every week.

## Types of Waterproofing We Install

### Exterior waterproofing

We excavate along the foundation down to the footing, clean the wall, repair cracks and parge it smooth, then apply an elastomeric waterproof membrane. A dimple drainage board, such as Delta-MS, goes over the membrane to protect it and give water a path down to the footing. New perforated weeping tile is laid in clear stone at the footing and connected to a sump or the storm system, then the trench is backfilled and graded away from the house.

### Interior waterproofing

Where exterior digging is not practical, under a driveway, a deck or a side yard too narrow even for us, we cut a channel around the inside perimeter of the basement floor, install a drain pipe in stone, connect it to a sump basin and pump, and finish the floor. Water may still reach the wall, but it is caught and removed before it reaches the floor.

### Sump pumps and backwater valves

A sump collects water from the weeping tile and pumps it out. A backwater valve stops city sewer backups from entering through floor drains. Both may qualify for the City of Toronto Basement Flooding Protection Subsidy.

### Waterproofing during underpinning

When we 

underpin

[/underpinning/ →](/underpinning/)

 or 

dig out

[/basement-excavation/ →](/basement-excavation/)

 a basement, the footings are exposed anyway. Adding new weeping tile, a sump and a membrane tie-in at that stage costs a fraction of doing it separately later.

![New perforated weeping tile laid in clear stone at the footing](/images/content/new-perforated-weeping-tile-laid-in-clear-stone-at.webp)

## Reading the Signs

| What you see | Likely cause | Usual fix |
| --- | --- | --- |
| Water at the floor-wall joint | Failed weeping tile, high water table | New weeping tile or interior perimeter drain |
| White powder on walls (efflorescence) | Water moving through masonry | Exterior membrane |
| Leaks at a crack | Cracked foundation wall | Crack repair plus membrane on that wall |
| Water after heavy storms at floor drain | Sewer backup | Backwater valve |
| Wet window wells | Poor drainage at the well | Well drain and grading |
| Damp but no visible water | Condensation or minor seepage | Grading, dehumidification, possibly membrane |

## Toronto Conditions That Cause Leaks

Toronto has some of the most leak-prone basements in Ontario. Houses built before the 1960s often have clay weeping tile that has cracked or silted up after decades. South Etobicoke, the Beaches and other lakeshore neighbourhoods sit on sand with groundwater close to the surface, which our Etobicoke client saw every spring until we dug out, replaced the weeping tile and waterproofed the exterior. Many older homes had weeping tile connected to the sanitary sewer, which can push sewage back into the basement during storms.

## The Rules and Permits

Excavating beside your foundation requires Ontario One Call locates, and gas meters and service lines often run right along the wall, so we daylight them first. Connecting a sump discharge or a severed weeping tile line has to follow the Toronto Sewer Use By-law, and backwater valves need a plumbing permit. If you plan to apply for the City subsidy, the work must meet the program’s conditions and you need the permit and invoices, which we provide.

## Get a Straight Answer

Some waterproofing companies sell one system to every house. We would rather tell you what your house needs. 

Book a free site visit

[/contact/ →](/contact/)

 and we will find the source of the water, explain your options and send a written quote within 24 hours. If the leak started after a sewer or water line failure, see our 

sewer and watermain

[/sewer-and-watermain/ →](/sewer-and-watermain/)

 service.

Toronto Pricing

## How Much Does Basement Waterproofing Cost in Toronto?

Typical range, per basement

$8K to $40K

Interior vs exterior, wall length and access drive cost.

**Timeline:** 3-10 working days

-   Interior drain and sump, one or two walls$8K-$15K
-   Exterior membrane, one side of house$12K-$22K
-   Full exterior perimeter with new weeping tile$25K-$40K

Get My Written Quote

[/contact/ →](/contact/)

CAD, before HST. Fixed price once signed, paid in 5 stage draws.

### What Moves the Price

| Cost driver | How it affects your quote |
| --- | --- |
| Exterior vs interior | Exterior work stops water at the wall but needs excavation; interior systems manage water inside and cost less where digging is hard. |
| Length of wall | Priced largely by the linear foot of wall treated. One leaking wall costs far less than the full perimeter. |
| Depth and access | Deeper basements and tight side yards mean more digging by hand or with compact machines. |
| Obstacles | Decks, porches, interlock and gas meters along the wall need removal and reinstatement. |
| Sump and backwater valve | Adding a sump pump and backwater valve adds cost but may qualify for the City subsidy. |

We do not give verbal estimates. Every number on this page is a planning range; your firm price comes in writing on letterhead within 24 hours of the site visit, with every line item shown.

Why Us

## Why Choose Pro Excavation Toronto for Waterproofing?

### Engineer's Honest Call

Our P.Eng tells you whether exterior or interior waterproofing suits your foundation, rather than selling the most expensive option.

### Excavation Specialists

Exterior waterproofing is mostly a digging job. We own the machines and handle narrow side yards and deep footings every week.

### Cheapest During Underpinning

If you are lowering the basement, we waterproof while the footings are already exposed, avoiding a second dig.

### Locates First

Gas meters and lines often run along the foundation. We daylight them before digging beside the wall.

### Subsidy Paperwork Help

We install backwater valves and sumps to the City's program requirements and supply the invoices you need to apply.

5-Stage Process

## How Does Our Waterproofing Process Work?

Every contract is fixed-price and paid in draws tied to these stages, so you only pay for work that is done and inspected.

1.  1
    
    ### Diagnosis
    
    Site visit
    
    We find where water is entering: cove joint, cracks, window wells, grading or a failed weeping tile, then recommend exterior or interior.
    
2.  2
    
    ### Excavation
    
    1-3 days
    
    Locates and daylighting, then dig down to the footing, protecting landscaping, with soil staged or hauled.
    
3.  3
    
    ### Membrane
    
    1-3 days
    
    Wall cleaned, cracks repaired, parged, membrane applied and dimple board installed over it.
    
4.  4
    
    ### Backfill
    
    1-2 days
    
    New weeping tile in clear stone, connected to sump or storm, then backfill compacted and graded away from the house.
    
5.  5
    
    ### Final
    
    Half day
    
    Sump and backwater valve tested, site restored, photos and warranty paperwork handed over.
    

## Not sure if you need underpinning or a bench footing?

Book a free site visit. Our P.Eng reviews the foundation before any deposit and tells you in writing which method fits your house and budget.

(647) 277-2002

[tel:+16472772002 →](tel:+16472772002)

 

Request a Free Site Visit

[/contact/ →](/contact/)

Our Work

## Waterproofing Project Photos

Real Toronto and GTA job sites. Click any photo to enlarge.

 

Case Studies

## Recent Waterproofing Projects

![Exterior basement waterproofing in Etobicoke with membrane, dimple board and new weeping tile](/images/features/etobicoke-exterior-basement-waterproofing-with-exc.webp) Residential $45K

Etobicoke

### Basement Excavation + Exterior Waterproofing

The basement flooded every spring because groundwater sits close to the surface near Lake Ontario. We excavated the exterior, installed an elastomeric membrane, dimple board, new weeping tile and clear stone, and added a sump. Fixed price, and the house stayed dry through the next spring melt.

Basement Waterproofing

[/basement-waterproofing/ →](/basement-waterproofing/)

![Underpinning in progress in a Leslieville semi with formed concrete pins along the foundation wall](/images/features/leslieville-semi-detached-basement-underpinning-in.webp) Residential $142K

Leslieville, Old Toronto

### Underpinning + Waterproofing, 6 ft 10 in to 9 ft 4 in

The quote went out 22 hours after the site visit. Pins were poured in engineered 1.2 m sequences with an inspection at each set, then the exterior was waterproofed and new weeping tile installed. The basement went from 6 ft 10 in to 9 ft 4 in and the job wrapped three weeks early.

Underpinning

[/underpinning/ →](/underpinning/)

See all projects

[/projects/ →](/projects/)

Client Results

## What Toronto Clients Say About Our Waterproofing

> "Our Etobicoke basement flooded every spring because of the high water table near the lake. They dug it out, replaced the weeping tile and waterproofed the exterior on a fixed price. The quote matched the final invoice exactly, and we stayed dry through the whole spring melt."

Sanjay R.

Etobicoke

Project value $45K

> "Quote in 22 hours. Underpinning finished 3 weeks ahead of schedule. P.Eng stamp handled every city inspection. Basement went from 6 ft 10 in to 9 ft 4 in."

Darren K.

Leslieville

Project value $142K

> "Burst Sunday morning. On-site in 3 hours. Hydrovac located the break, trenchless repair by Tuesday. Insurance direct-billed through the portfolio adjuster."

Priya S.

Property Manager, North York

Project value $28K

Straight Answers

## Waterproofing FAQs

### How much does basement waterproofing cost in Toronto?

Most Toronto basement waterproofing costs $8K to $40K. An interior perimeter drain and sump along one or two walls usually costs $8K to $15K. Exterior waterproofing on one side of a house, with excavation, membrane, dimple board and new weeping tile, is commonly $12K to $22K. Doing the full exterior perimeter is usually $25K to $40K. Prices depend on wall length and depth, access, obstacles like decks and porches, and whether a sump and backwater valve are added. If you are underpinning or doing a dig-out, adding waterproofing at the same time costs far less because the footings are already exposed. We give you a written quote within 24 hours of diagnosing the leak.

### Is exterior or interior waterproofing better?

Exterior waterproofing stops water before it reaches the wall, which protects the foundation and keeps the basement drier, so it is usually the better long-term fix. It needs excavation along the wall, which is harder on narrow Toronto lots or under decks and driveways. Interior waterproofing lets water reach the wall but catches it in a perimeter drain and pumps it out. It costs less and suits tight lots, but the wall stays wet. Our P.Eng looks at your foundation, access and the source of the water and tells you which makes sense. Sometimes the answer is exterior on one side and interior on another.

### What is weeping tile and why does it fail?

Weeping tile is the perforated drain pipe around the footing that collects groundwater and carries it away. Older Toronto houses have clay tile that cracks, fills with silt or gets invaded by roots, and many were connected to the sanitary sewer. When it fails, water builds against the wall and comes in at the cove joint. Replacing it with modern pipe in clear stone, connected to a sump, fixes the root cause.

### Does the City of Toronto offer a subsidy?

The City of Toronto runs a Basement Flooding Protection Subsidy Program that has covered part of the cost of a backwater valve, a sump pump and severing the weeping tile connection from the sewer. Amounts and conditions change, so check the City's current program. We install to the program requirements and provide the invoices and permit documents you need.

### What is a backwater valve?

A backwater valve is a one-way valve on your main sewer line that closes if the city sewer backs up, so sewage cannot flow into your basement during heavy storms. It needs a plumbing permit and periodic cleaning.

### Why does water come in where the wall meets the floor?

That is the cove joint. Water pressure builds under the slab and against the wall when the weeping tile fails or the water table is high, and the joint is the weakest point. Exterior waterproofing with new weeping tile or an interior perimeter drain relieves that pressure.

### How long does exterior waterproofing take?

Most jobs take 3 to 10 working days, depending on the length of wall and how many obstacles need removing and reinstating.

### Will you damage my landscaping?

We protect what we can and reinstate what we move. Gardens, interlock and decks along the wall are noted at the site visit and their removal and reinstatement is priced up front.

### Do you waterproof during underpinning?

Yes. It is the cheapest time to do it, because the footings are already exposed. Most of our underpinning projects include new weeping tile, a sump and membrane tie-in.

Often Paired With

## Related Services

Most projects touch more than one trade. These are the services we most often combine with this one, quoted on the same letterhead.

 

![Basement underpinning in progress in a Toronto Victorian semi with concrete pins formed under the old footing](/images/misc/toronto-victorian-semi-basement-underpinning-in-pr.webp) Hero Service

[/underpinning/ →](/underpinning/)

### 

Underpinning

[/underpinning/ →](/underpinning/)

$30K-$200K

Lower your basement below the existing footing with P.Eng stamped 1.2m sequencing, permits handled and party walls protected.

P.Eng StampedToronto Building LiaisonParty-Wall Protection

Get an Underpinning Quote for Underpinning

[/underpinning/ →](/underpinning/)

![Basement dig-out in progress in a Toronto house with a mini-excavator inside and a conveyor carrying soil out](/images/misc/toronto-basement-dig-out-in-progress-with-old-slab.webp)

[/basement-excavation/ →](/basement-excavation/)

### 

Basement Excavation

[/basement-excavation/ →](/basement-excavation/)

$12K-$45K

Interior dig-outs, crawlspace conversions and new-build basement digs using tight-access conveyors and mini-excavators.

Conveyor SystemsTight-Access RigsClean-Site Protocol

Quote My Dig-Out for Basement Excavation

[/basement-excavation/ →](/basement-excavation/)

 

![Emergency watermain repair in front of a Toronto house with a hydrovac truck exposing the break](/images/misc/emergency-watermain-repair-in-front-of-a-toronto-h.webp) 24-Hour Emergency

[/sewer-and-watermain/ →](/sewer-and-watermain/)

### 

Sewer and Watermain

[/sewer-and-watermain/ →](/sewer-and-watermain/)

$8K-$80K

Sewer lateral and water service replacement, trenchless or open-cut, with 24-hour emergency response and insurance direct-bill.

24-Hour EmergencyTrenchless OptionsInsurance Direct-Bill

Call the 24-Hour Line for Sewer and Watermain

[/sewer-and-watermain/ →](/sewer-and-watermain/)

![Backyard pool excavation in a Toronto yard with a mini-excavator and protected lawn](/images/misc/backyard-pool-excavation-in-a-toronto-residential-.webp)

[/residential-excavation/ →](/residential-excavation/)

### 

Residential Excavation

[/residential-excavation/ →](/residential-excavation/)

$5K-$40K

Driveway, pool, retaining wall and backyard digs with mini-excavators sized for narrow Toronto side yards.

Tight Side-Yard AccessSame-Day Haul-OffLocates First

Quote My Project for Residential Excavation

[/residential-excavation/ →](/residential-excavation/)

![](/images/misc/wide-dusk-view-of-a-clean-organized-toronto-underp.webp)

Site visit in 48 hours

## Ready for Waterproofing Done Properly?

We walk your site within 48 hours and send a fixed-price CAD quote on letterhead within 24 hours after. P.Eng stamped where required, and no change orders without your written approval.

Request a Free Site Visit

[/contact/ →](/contact/)

 

Call (647) 277-2002

[tel:+16472772002 →](tel:+16472772002)

-   Fixed-price, 5-stage draws
-   $5M liability + WSIB
-   24-hour emergency water + sewer line