The same crack can be a closed item or an open dispute depending on one thing: whether it was documented when it was first noticed. That boundary, not any single defect, is what repeats.
Key takeaways
Tarion does not publish a ranked list of the most common warranty defects, and a builder looking for one is asking the wrong question. What actually repeats is not a specific defect — a crack, a leak, a door that sticks — but the boundary dispute underneath it: was this documented when it happened, and does it clear the bar for coverage at all. The same physical issue lands on opposite sides of that boundary depending on when it was noticed and how it was recorded.
The PDI form itself sets the vocabulary every later claim gets measured against: items are logged as “incomplete, damaged, missing, inaccessible or not operating properly”. That five-word taxonomy is doing more work than it looks like — an item that is “not operating properly” at the PDI and still isn’t fixed by year-end is a straightforward claim with a paper trail. The same item, first mentioned to Tarion a year after possession with nothing recorded at the PDI, is a much harder case to establish, because purely cosmetic issues discovered well after possession, without documentation, can be harder to establish.
Tarion’s Construction Performance Guidelines exist for exactly this reason: they are described as providing advance guidance as to how Tarion will decide disputes between homeowners and builders regarding defects in work or materials. The guidelines are said to complement, not replace, the Ontario Building Code — they are the yardstick Tarion applies to a workmanship dispute, separate from whichever code section might also be in play.
A separate set of items never reach the documentation question because they are excluded on their face: ordinary wear and tear that comes with normal use over time, damage from alterations, renovations or work the homeowner had done after taking possession, or from misuse, neglect or accidents unrelated to construction quality, and appliances such as a fridge, stove or dishwasher — which fall under the manufacturer’s warranty rather than Tarion’s. indirect losses like temporary accommodation costs or lost time also receive limited or excluded coverage, a distinction worth explaining up front rather than after a homeowner has already assumed a hotel stay during repairs is covered.
The second boundary that repeats sits inside items that clearly are covered: whether something is an ordinary warranty item or a major structural defect. Tarion’s own bulletin structure treats the two very differently — the definition turns on a defect in a structural load-bearing component that results in the failure of a load-bearing element, or a defect that materially and adversely affects the use of the building as a home, and settlement cracks that are cosmetic in nature typically do not meet that threshold. A structural engineer’s assessment is typically what actually settles which side of that line an item falls on; a builder or homeowner asserting either outcome without one is arguing from opinion rather than evidence.
Tarion’s own coverage guide states the definition in three parts, not the two most summaries carry: a major structural defect is one that results in failure of a structural load-bearing element; materially and adversely affects the ability of a structural load-bearing element to carry, bear and resist applicable structural loads for the usual and ordinary service life of the element; or materially and adversely affects the use of a significant portion of the building for the usual and ordinary purposes of a residential dwelling. The middle branch is the one most summaries drop, and it is doing real work — a load-bearing element that is still standing but no longer rated to carry its design load for its expected service life clears the definition without ever failing outright.
Treadstonelaw’s own guidance flags a related trap worth repeating to a homeowner directly: “normal settling” is sometimes used to dismiss claims, and is worth verifying rather than taking as a given explanation, a phrase used often enough that it is worth confirming rather than accepting on its face.
Coverage and cost are two separate questions, and conflating them is its own recurring mistake. Tarion’s RB04, How Chargeability is Determined and Applied, effective May 1, 2024 governs a distinct question from whether an item is covered at all — whether it is the builder who is financially on the hook for it, which is not always the same answer. A builder tracking which defects recur across a project should be tracking chargeability alongside coverage, not assuming the two move together, and managing claim volume after occupancy is the place that volume actually gets felt operationally.
Two homeowners each report a drywall crack above an interior door frame. The first flagged it at the PDI, and it was logged on the PDI form as an incomplete or damaged item; when it reappears at the Year-End Form eleven months later, the file already shows it was known from day one, and the question is simply whether the repair held, not whether the claim is legitimate. The second homeowner never mentioned it until the Year-End Form, with nothing recorded at the PDI — the crack may be identical, but the builder is now working from a purely cosmetic issue discovered late, without documentation — the exact combination Tarion’s exclusions guidance flags as harder to establish.
Contrast that with a basement wall showing a visible bow rather than a hairline crack. Here the CPG’s cosmetic-tolerance framing does not apply at all — a bowing wall is a candidate for the load-bearing question, not the documentation one, and the right next step is an engineer’s assessment rather than a PDI-record check. Sending a documentation dispute down the structural-assessment path wastes an engineer’s time and a homeowner’s patience; sending a genuine structural concern down the documentation path risks missing something that needed to be caught early. Sorting a reported item into the right boundary as soon as it is raised — documentation dispute or structural question — determines which evidence actually matters, and disciplined PDI scheduling and a communication cadence that surfaces issues early are the two upstream habits that keep the first boundary from swallowing items that never needed it.
No. Appliances such as a fridge, stove or dishwasher are generally covered by the manufacturer's own warranty rather than Tarion's statutory new home warranty.
A major structural defect is a defect in a structural load-bearing component that results in the failure of a load-bearing element, or that materially and adversely affects the use of the building as a home. Cosmetic settlement cracks typically do not meet that threshold, and a structural engineer's assessment is usually what settles the question.
Purely cosmetic issues discovered well after possession, without documentation from the PDI, are harder to establish than the same issue logged at the inspection itself -- the PDI record is the evidence a later claim gets measured against.
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