Basement Leaks and Foundation Drainage in London Ontario Townhouse Condos: What Boards Should Do
(From a Condominium Management Expert)
A heavy rain or a fast spring thaw hits a London Ontario townhouse community, and by morning the board has three emails about wet basement floors. One owner has a damp corner, another has water along a crack in the wall, and a third says it happens every year. Your corporation already has a manager, yet each leak gets handled as a one-off call instead of a building problem.
Basement leaks in townhouse condos usually come back to the same few causes: grading, eavestroughs and downspouts, foundation cracks, weeping tiles and sump pumps. This guide covers who is responsible under sections 90 and 91 of the Condominium Act, 1998, how to find the real cause, how to fund a drainage repair and what the City of London and City of Sarnia grant programs say about condominiums. It is written for boards in London Ontario and Sarnia Ontario.
Who is responsible for a basement leak in a townhouse condo in Ontario?
It depends on your declaration, but in many townhouse corporations the foundation walls, exterior drainage and grading are common elements, so the corporation is responsible. This is not legal advice, but generally speaking under Ontario law, section 90 (1) of the Condominium Act, 1998 says the corporation shall maintain the common elements and each owner shall maintain the owner's unit.
Section 91 lets a declaration change that split, so some townhouse declarations make owners responsible for parts of their own home or the exclusive use areas around it. Read the declaration and description before anyone promises a repair, and ask your manager to confirm in writing which parts belong to the corporation. Damage inside the unit, such as flooring and drywall, follows the repair after damage rules in section 89 and the standard unit by-law. Our guide Water Damage in Ontario Condos: Who Is Responsible? (https://sapphirecondomgmt.ca/water-damage-condo-responsibility-ontario) explains how that part works.
What usually causes basement leaks in townhouse condos?
Most townhouse basement leaks start outside the wall, where water is collecting against the foundation instead of moving away from it. Fixing the outside cause usually solves the problem for longer than sealing the inside of the wall.
The common sources to check are:
• Grading that has settled and now slopes toward the foundation instead of away from it
• Eavestroughs that overflow and downspouts that empty right beside the wall or into a buried pipe
• Cracks in the foundation wall, or a gap where pipes and wires pass through it
• Weeping tiles around the footing that are blocked, collapsed or connected to the wrong sewer
• Sump pumps that have failed, have no backup or discharge too close to the building
• Window wells and patio slabs that hold water against the wall
When the same block of units leaks after every storm, treat it as one problem with one cause, not as separate owner complaints.
How should a board investigate a recurring basement leak?
Start with records, then bring in an independent professional before any contractor quotes a fix. A board that hires a waterproofing contractor first often gets a solution sized to what that contractor sells, not to the cause.
Ask your manager to pull together:
• A log of every leak report by unit, date and weather, without owner names
• Photos of the grading, downspouts and wall cracks at each affected unit
• The drainage and foundation lines of the latest reserve fund study
• Any past repair invoices and warranties for foundation or drainage work
• A camera inspection of the weeping tile and sewer connections where leaks repeat
An engineer can then review that information and write a scope the board can tender. Section 19 of the Condominium Act, 1998 lets the corporation enter a unit on reasonable notice to carry out its duties, so give owners clear notice of inspection dates. London Ontario townhouse boards working with Sapphire Condominium Management get this kind of vendor coordination as part of full management, which we describe in Townhouse Condo Management in London Ontario (https://sapphirecondomgmt.ca/townhouse-condo-management-london-ontario).
How does a condo corporation pay for foundation and drainage repairs?
Regrading, small crack repairs and downspout changes usually come from the operating budget, while larger work such as excavating and waterproofing foundation walls or replacing weeping tiles is usually reserve fund work. Section 93 (2) of the Condominium Act, 1998 says the reserve fund shall be used solely for major repair and replacement of the common elements and assets of the corporation.
Check whether your reserve fund study already includes foundations and site drainage, and whether the funding plan has kept up. Section 94 (1) requires periodic reserve fund studies, and our guide Reserve Fund Studies in Ontario: What Every Board Must Know (https://sapphirecondomgmt.ca/reserve-fund-study-ontario-condo-board-guide) explains how to read one. If you would like a second opinion on how your reserve fund and financial statements line up with a drainage project, you can request a free financial review on us.
Insurance is a separate question. Section 105 (1) makes the deductible on the corporation's policy a common expense, and section 105 (2) can shift it to an owner whose act or omission caused the damage to their unit. Talk to your insurer or broker before deciding how a claim is handled.
Can a London or Sarnia condo corporation get a basement flooding grant?
In London, generally no. The City of London's Basement Flooding Grant Program page states that condominiums are not eligible, other than vacant land condominiums. In Sarnia, the City's Basement Flooding Grant Program lists a condominium corporation among the owners who can apply.
Both programs share one rule boards should know before booking work. London says applicants must not have started construction, and Sarnia says the owner must not start the work before grant approval. Sarnia also requires permits: a plumbing permit through Lambton County for a backwater valve and a City building permit for foundation drain disconnection and a sump pit. Ask your manager to check the current program pages before the board signs a contract. London's Drainage By-law WM-4 also matters, because it says foundation drain flows go by sump pump to the ground surface or a storm sewer, not the sanitary sewer.
Frequently Asked Questions
Q: Who pays for a basement leak in a townhouse condo in London Ontario?
A: Usually the corporation pays to fix the cause when the foundation walls and exterior drainage are common elements, because section 90 (1) of the Condominium Act, 1998 puts common element maintenance on the corporation. Your declaration can change that under section 91, so read it first. This is not legal advice.
Q: Should a condo board hire an engineer for a foundation leak?
A: For a leak that keeps coming back, yes. An independent engineer can find the cause and write a scope, so contractors bid on the same work. Boards in London and Sarnia that tender a written scope compare quotes fairly and avoid paying for a fix that only treats the inside of the wall.
Q: Are condos eligible for the City of London basement flooding grant?
A: The City of London's program page says condominiums are not eligible, except vacant land condominiums. Sarnia's program lists condominium corporations as eligible applicants. In both cities, apply and get approval before any work starts, and check the current program page first because rules change.
Related Reading
→ Water Damage in Ontario Condos: Who Is Responsible?
→ Townhouse Condo Management in London Ontario: Is Your Manager Covering the Basics?
→ Reserve Fund Studies in Ontario: What Every Board Must Know