Buyer

April 12, 2021

Updated September 2026

A finished basement, a new deck, an opened-up kitchen. Renovations can make a home, but if the work was done without the permits it needed, the new owner can inherit the problem. Here is what to watch for when you are buying in Ontario, and how to protect yourself before your offer is firm.

What needs a permit in Ontario

Building permits are issued by your local municipality under the Ontario Building Code, and the details vary from town to town. As a general guide, permits are usually needed for work such as:

additions, and removing or moving walls
new window or door openings where there weren't any before
finishing a basement when it involves structural changes, plumbing or heating changes, or a second unit
decks more than 60 cm (24 inches) above the ground
installing or changing plumbing or heating systems, fireplaces and chimneys

Work that usually doesn't need a building permit includes new cabinets, flooring and painting, replacing shingles with no structural work, and replacing a window in the same opening. Always check with the municipality where the home is; the City of Toronto, for example, publishes its own list.

Electrical work is separate. The Electrical Safety Authority requires almost all electrical work in Ontario to be reported through a notification of work (often called an ESA permit), even when a homeowner does the work. A building permit and an ESA notification are not the same thing, and a project may need both.

Why unpermitted work is a risk for buyers

Safety. Permits come with inspections. Without them, no one has checked the framing, fire separation, wiring or plumbing.
Orders from the municipality. If the municipality finds out, it can require the work to be opened up, brought up to code or removed, and the current owner pays for it.
Insurance. Tell your insurer about major renovations. Unpermitted work can create problems with coverage.
Financing and resale. Lenders and future buyers ask questions too. An unpermitted basement apartment, for example, may not count as legal rental income.
Cost. Getting old work approved after the fact can mean opening walls, engineering drawings and upgrades.

How to check before you buy

Ask the seller. Ask what work was done, when, and whether permits were taken out and closed. Ask for copies.
Search the municipality's records. Most municipalities will search their building records for a property, including open permits and outstanding orders. There is usually a fee and it can take time, so request it early.
Ask about electrical work. Find out whether it was done under an ESA notification.
Get a home inspection. A good inspector will point out work that looks recent or amateur, such as newer drywall in a basement, do-it-yourself wiring or a deck without proper footings. See our list of home inspection red flags.
Let your lawyer do their searches. Your real estate lawyer checks for work orders and other issues registered against the property before closing.

What to do if you find unpermitted work

Write it into your offer. Your agent can add conditions for an inspection or a permit search, and clauses asking the seller to confirm what work was done and whether it was permitted.
Price it in. Get an estimate for bringing the work up to code, and negotiate from there.
Ask for it to be fixed or documented before closing, if there is time.
Walk away if the risk is too big, for example structural changes with no engineering behind them.

Does title insurance cover it?

It can help, within limits. According to FCT, a title insurer, title insurance can cover losses when a municipality requires a previous owner's unpermitted work to be removed or repaired, and it may compensate for lost property value from that compliance work. It doesn't cover the quality of the work itself or physical damage, and policies generally exclude problems you knew about before you bought. Ask your lawyer exactly what your policy covers.