TREADSTONE LAW · ONTARIO · DIGITAL LEGAL SERVICES · EST. MMXXI ·TSL
Licensed by the Law Society of OntarioFlat fees published upfrontWe reply to messages within 1 business daySign in
Home/Articles/Real Estate
№ 22 Real Estate

Hidden Defects After Buying a House in Ontario: Can You Sue?

Found a serious problem after closing? Learn what a hidden defect is, why inspection conditions and permits matter, and when to talk to a lawyer in Ontario.

Real Estate4 min readTSLBy the Treadstone Law Team · OntarioUpdated November 13, 2026
← All articles
Key takeaways
  • Whether you can claim for a hidden defect depends on the facts, your agreement and the law, so it is worth getting legal advice early.
  • An inspection condition must be waived or performed by the agreed time, and once all conditions are waived the agreement is firm and binding.
  • New homes may carry Tarion warranty coverage with its own forms and timelines.

You have closed, moved in, and then found a serious problem: water in the basement, a failing structure, or work that was never properly done. You may wonder whether the old idea of buyer beware means you are stuck with it.

There is no simple yes or no. Whether you have a claim depends on the details of your situation, including what was wrong, what the seller said and what your agreement says, so it is worth confirming with a lawyer. This article explains what you can check, what to gather, and when to see a lawyer.

What a hidden defect usually means

Whether a particular problem counts as a hidden defect depends on the facts of your situation. How it applies to you is worth confirming with a lawyer.

Whether buyer beware limits your options also depends on the facts and on court decisions. Be cautious about any online summary that promises a clear answer, and consider getting advice about your own situation.

Why the inspection condition and agreement matter

Conditions such as a satisfactory home inspection must be waived or performed by the agreed time before the deal becomes binding, and they must be used in good faith. Depending on how the condition is worded, if it is not met the buyer may terminate or the contract may end automatically, with the deposit returned. Once all conditions are waived, the agreement is firm and binding.

How your steps before closing affect a claim afterward depends on your situation, so it is worth confirming with a lawyer. Your agreement of purchase and sale, any seller disclosure documents and the listing are worth keeping together, along with any inspection report.

Permits and renovations

Buyers are told to find out whether proper permits were obtained for any renovations. In Ontario, a building permit is required before most construction, additions, renovations and changes of use, and the municipal building department can confirm what permits exist for a property.

If your problem comes from past renovation work, a check with the municipal building department may help show what was approved. It will not settle whether you have a legal claim, but it is useful information to bring to a lawyer.

If the home was newly built

New homes can come with Tarion warranty coverage. The one-year warranty starts on the date of possession (occupancy date for a condominium). The two-year warranty covers items such as water penetration and heating and electrical systems. The seven-year warranty covers major structural defects and runs to the seventh anniversary of possession.

Tarion claims use specific forms and timelines:

What to do next

Frequently asked questions

Can I sue the seller for a hidden defect?

Sometimes, but it depends on the facts, your agreement and the law. A lawyer can review what the seller said and knew, what you could have discovered, and what your options are.

Does waiving my home inspection end my options?

Whether waiving an inspection affects a claim for a hidden problem depends on your situation, so it is worth confirming with a lawyer. Conditions such as a satisfactory home inspection must be waived or performed by the agreed time before the deal becomes binding, and once all conditions are waived, the agreement is firm and binding. A lawyer can explain how that affects a claim for a hidden problem.

Does Tarion cover a serious structural problem?

For a new home, the seven-year warranty covers major structural defects and runs to the seventh anniversary of possession. The Major Structural Defect Form can be filed after year two, but no later than seven years from possession.

Should I check permits after finding a problem?

It is a sensible step. The municipal building department can confirm what permits exist for a property. The result can help a lawyer assess your situation.

Sources

Links go to official government, court and regulator pages. The law changes — confirm you are reading the current version.

This article is general information, not legal advice. Reading it does not create a lawyer-client relationship. Ontario laws, tax rates, and government programs change, and how the law applies depends on your specific facts. For advice about your situation, speak with a licensed Ontario lawyer. Treadstone Law is licensed by the Law Society of Ontario — reach us at 1-844-900-1070 or start a file online.

This is a real estate question

Start a file online — flat, published fees, reviewed by a licensed lawyer before a dollar is owed.

ContactStart a File →