You moved in, then the problem appeared: a recurring infiltration, a foundation that is moving, mould behind a wall, plumbing that fails. Nothing hinted at it when you bought — and yet, it was there. In Quebec, this type of defect has a name: the latent defect (vice caché). But between noticing it and obtaining compensation, there is a step many underestimate: proving it. And that is precisely where the outcome of a claim is decided.
At Boreon, we do not operate on the legal terrain — that is lawyers’ work. Our role is upstream, and it is decisive: rigorously documenting the technical reality of the defect, analyzing its probable causes, and producing a solid and defensible report that your case can rely on. This article explains what a latent defect is, the deadlines to know, and why the quality of the proof often makes all the difference.
What is a latent defect, in the eyes of the law?
Not every defect in a property is a latent defect. For a problem to qualify as one, it must generally meet four conditions:
- It is hidden (not apparent): a prudent and diligent buyer could not detect it during a normal examination, without particular expertise.
- It is serious: it makes the property unfit for its intended use, or so reduces its usefulness that the buyer would not have bought it — or would have paid less — had they known.
- It predates the sale: the defect, or its cause, already existed at the time of purchase.
- It was unknown to the buyer at the time of the transaction.
This article is provided for information and does not constitute legal advice. The qualification of a latent defect, the deadlines and the recourses depend on each situation and are a matter for a lawyer. Our focus is the technical dimension — the documentation and analysis of the defect.
It is this combination that makes latent-defect files demanding: it is not enough for a problem to exist, you must show that it meets these conditions. An infiltration that was visible and reported before the purchase is not a latent defect; an infiltration whose cause was concealed and pre-existing can be.
Deadlines: why time works against you
In matters of latent defects, acting quickly is not an option, it is a necessity — for two distinct reasons.
First, notice to the seller. As soon as the problem is discovered, the law generally requires the buyer to notify the seller, in writing, within a reasonable time, before undertaking work. Skipping or delaying this step can weaken, even compromise, a claim.
Then, prescription: the time limit to bring an action generally runs from the discovery of the defect, not from the purchase. This period is limited — hence the importance of not letting it drag on.
The exact deadlines (notice, prescription) and how to respect them depend on your situation: consult a lawyer without delay. On our side, the sooner the defect is documented, the better your case is protected.
In latent defects, the worst technical mistake is to repair before documenting: you fix the symptom, but you destroy the proof.
The mistake that costs the most: repairing before documenting
It is the natural reflex — and it is often a fault. Faced with water damage or mould, you want to fix the problem immediately. But by repairing before an expert has observed and documented the state of the premises, you risk erasing the very proof of the defect’s existence and cause.
Yet a claim does not rest on an impression or a testimony: it rests on a demonstration. The probable cause, the extent, the pre-existence, the hidden nature of the defect — all of this must be established, ideally before any corrective intervention. The golden rule: document first, repair later (except in an emergency to limit the damage, and even then, documenting as much as possible beforehand).
The heart of the case: rigorous technical proof
A latent-defect dispute is largely won or lost on the quality of the technical proof. This is our trade. Concretely, serious technical expertise includes:
- a visit and a targeted inspection of the defect and its surroundings;
- documentation of the deficiencies: annotated photos, precise descriptions, measurements;
- analysis of the probable causes — where the problem really comes from, and since when;
- a reading of the impact of the defect on the building and on its value;
- a structured, defensible report, written to professional standards.
500+ projects documented on site, including complex files in Quebec
This report is designed to be usable where it counts: before the Administrative Housing Tribunal, before the civil courts, or with an insurance company. Its strength rests on three things: the rigour of the method (grounded in building science), the clarity of the presentation, and our total independence — we have no stake in the outcome of the dispute, which gives weight to our findings.
Latent defect or simple wear? The nuance that changes everything
Part of the work is precisely to tell a genuine defect apart from normal wear, a maintenance failure or an apparent problem. Not every post-purchase inconvenience gives rise to a claim, and presenting a poorly qualified file works against the buyer. Conversely, a defect that seems trivial can reveal, on analysis, a far more serious pre-existing and concealed cause.
That is why a neutral technical eye, upstream, has a double value: it strengthens solid cases by supporting them, and it avoids launching costly proceedings on fragile grounds. In both cases, it is the client’s interest that is served.
Our role, plainly
Boreon documents and analyzes; lawyers plead. We respect that boundary — and that is what makes our work useful. We provide the technical material on which a case is built: a rigorous finding, established probable causes, a defensible report. Our inspectors are InterNACHI-certified, we hold professional liability insurance, and we act in full independence, with no conflict of interest. Because these mandates vary in complexity, the schedule is agreed in advance. We cover Montreal and all of Greater Montreal — West Island, South Shore, Laval and North Shore.
Key takeaway
A latent-defect claim rests on proof. Before repairing, have the defect documented: act quickly (notice and prescription deadlines), consult a lawyer for the legal side, and support your case with rigorous, independent technical expertise. That is what turns an endured problem into a defensible case.
Discovered a defect after buying your property? Have the situation documented by Boreon — a clear, defensible technical report to support your steps.
