Anonymised, illustrative composite. A home sold again after nine years, and the new listing reused the old MLS record's stated square footage rather than remeasuring the finished space.
At a glance
A detached home in London relisted nine years after its last sale. Rather than remeasuring, the relisting agent pulled the square footage straight from the prior MLS record — 2,340 sq ft — on the reasonable-sounding assumption that a house's footprint doesn't change. This one's usable area had, because of work done in between listings, not the shell.
The sellers had built an interior stairwell to finish the basement partway through their ownership, taking a bite out of main-floor square footage that the original figure never accounted for. The buyer's mortgage lender required an appraisal before releasing final approval; the appraiser's own measurement came back at 2,265 sq ft — a 75 sq ft, roughly 3%, gap from the marketed number. The lender flagged the discrepancy and paused approval pending an explanation.
The gap itself — 2,340 sq ft marketed against 2,265 sq ft appraised — is a fact about this specific property at this specific point in its ownership, not a general measurement-error rate; no Canadian source publishes a typical or expected square-footage discrepancy for a resale listing, and none should be invented to fill that gap. What is a fact independent of any one file is that the figure had never been re-verified across nine years and at least one interior renovation.
There is no single mandated measurement protocol a Canadian real estate regulator publishes and enforces the way a building code enforces construction — RECO's own bulletins, checked directly, carry no dedicated square-footage or measurement-standard bulletin. What governs instead is the general representation rule: a stated figure is a representation like any other, and the Competition Act s.52 prohibits a representation to the public that is false or misleading in a material respect, full stop, with no carve-out for a figure that used to be accurate. On top of that floor, s.74.01(1)(b) treats a performance claim as reviewable conduct where it is “not based on an adequate and proper test thereof, the proof of which lies on the person making the representation” — the burden sits with whoever states the number to have had a real basis for it, not with the buyer to disprove it after the fact.
Copying a nine-year-old figure forward is not, on its own, an adequate basis for a current representation once the space has changed — and under s.74.01(1)(b) the agent would carry the burden of showing the figure was reasonably supportable when it was republished, not simply that it had been true once.
The brokerage commissioned an independent measurement, corrected the listing to 2,265 sq ft, and provided the lender with the updated figure and the appraiser's report. The lender's approval proceeded on the corrected number; the buyer, already committed to the property, did not renegotiate price over a 3% gap once the correction was documented and explained. A larger gap, or one surfacing after an unconditional close instead of during financing, would not have resolved as easily — a buyer who closes on a stated square footage that turns out to be materially overstated has a live basis to argue reliance on a false representation, with no financing-stage off-ramp left to use instead.
The tell was treating a nine-year-old figure as a fact rather than as someone else's old representation. A square-footage number on an MLS record is only as reliable as whoever last measured it and whatever has changed since — a finished basement, a converted garage, an added stairwell, a removed wall all move the number, and none of them show up in a shell measurement or a tax-assessment record. The standing fix, adopted after this file: remeasure or reverify before republishing any figure on a listing that last sold more than a couple of years earlier, rather than trusting the prior record.
The nine-year gap is itself informative. A figure copied forward six months after the last listing carries a reasonable presumption nothing has changed; a figure copied forward across nearly a decade of a family's ownership carries no such presumption, because a decade is long enough for almost any interior renovation to have happened without a permit search or an exterior photo ever revealing it. Age of the source record is its own risk signal, independent of whether anything in it was ever actually wrong when it was first measured.
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