Seller Disclosure Obligations in Ontario — What You Must Reveal

I knocked on the door at 242 Trafalgar Road this morning and the seller greeted me with a nervous smile, clutching a manila folder thick with receipts. "I want to make sure I'm disclosing everything properly," she said, and I could hear the anxiety in her voice. The house was a beautiful 1970s split-level, but I could already see the telltale signs of someone who'd been losing sleep over what they needed to reveal to potential buyers. Sound familiar?

Here's what I've learned after 15 years of inspections: sellers in Ontario are walking a tightrope when it comes to disclosure, and most of them don't even know where the rope is. You're legally required to disclose any latent defects you know about, but the word "know" is doing a lot of heavy lifting there. What I find most concerning is how many sellers think ignorance will protect them.

Let me tell you about that Trafalgar Road house. The seller showed me her folder of documentation for a foundation repair that cost $12,350 back in 2019. Smart move. She had the contractor's report, the before and after photos, even the warranty paperwork. But then she mentioned something that made my blood pressure spike.

"The basement had a bit of water come in during that big storm last spring, but it was just from the foundation work settling," she said. "I didn't think I needed to mention it since it was related to something we already fixed."

That's a separate water intrusion event, and buyers need to know about it. Even if it's related to previous work, even if it only happened once, even if you're convinced it won't happen again. I've seen sellers get sued for exactly this kind of reasoning, and it's not pretty.

The disclosure requirements in Ontario aren't just about being nice to buyers. They're about protecting yourself from lawsuits that can drag on for years and cost more than your commission. You must disclose any material latent defects that you're aware of. Material means it affects the value or desirability of the property. Latent means it's not obvious to a reasonable buyer during a typical viewing.

Buyers always underestimate how much detective work goes into buying a house in neighbourhoods like Glen Abbey or Old Oakville. These 1980s and 1990s builds have their quirks, and sellers often know exactly where the bodies are buried. That slight bow in the family room ceiling? You know it's from the upstairs bathroom leak three years ago. The fact that the basement stays cooler than it should? You know it's because the ductwork was damaged during that reno in 2021.

What surprises me most is how often sellers think cosmetic fixes erase disclosure obligations. Just last week I inspected a house on Speers Road where the sellers had beautifully refinished the basement after a sewage backup. Gorgeous work, you'd never know anything happened. But guess what we found during the inspection? The insurance claim paperwork sitting right there in the utility room filing cabinet. The buyers' lawyer had a field day with that one.

I always tell my clients to think about disclosure as insurance, not liability. When you properly document and disclose issues, you're protecting yourself. When you hide them or hope they won't be discovered, you're setting yourself up for problems that will follow you long after the keys change hands.

Here's my rule of thumb: if you've ever called a contractor, filed an insurance claim, or noticed something that made you think "I should probably get that looked at," it needs to be disclosed. The kitchen faucet that needs to be jiggled just right? Disclose it. The garage door that sticks in humid weather? Disclose it. The weird smell in the powder room that comes and goes? Definitely disclose it.

The disclosure statement isn't a confession booth, it's a business document. You're not admitting fault, you're providing information that allows buyers to make informed decisions. In 15 years I've never seen a seller get in trouble for disclosing too much, but I've seen plenty get burned for disclosing too little.

Now here's where it gets tricky. You don't have a duty to investigate or hire inspectors to find problems before you sell. If you genuinely don't know about an issue, you can't be expected to disclose it. But once you know, you can't unknow. That's why some sellers tell me they specifically avoid getting inspections before listing. I understand the logic, but it's risky thinking.

What about that foundation repair on Trafalgar Road? I recommended the seller update her disclosure to include the 2024 water intrusion as a separate item, with a clear explanation of what happened and what steps were taken. Yes, it might concern some buyers. But it's better than dealing with a lawsuit in 2026 when the new owners discover the water damage evidence during their own renovation project.

The spring market is coming up fast, and I'm already seeing sellers in Bronte and throughout Oakville preparing their disclosure statements. Remember that buyers in this price range, especially at $1.4M average, tend to be sophisticated and thorough. They hire good lawyers and experienced inspectors. They find things.

Don't let disclosure requirements keep you up at night here in Oakville. Get organized, be honest, and document everything properly. Your future self will thank you for it.