Condo Square Footage in BC: Why the Listing Number Might Be Wrong

A condo listing says 920 square feet. The strata plan says something else. The appraiser measures it and comes back with a third number. All three describe the same unit, and none of them is lying. They just measured different things in different ways. For a first-time buyer comparing units by price, that gap can quietly cost you.

Square footage feels like a hard fact, the kind of number you can trust. In practice it is one of the softer numbers in a real estate deal. Here is how condo and townhouse size gets measured in the Fraser Valley, why the figures disagree, and what to check before you pay a price built on a number you never confirmed.

Where does the listing square footage come from?

The number on a listing has to come from somewhere, and it is worth knowing which somewhere. Sometimes it is copied from the developer's original marketing brochure. Sometimes it is pulled from an old MLS® record from a previous sale. Sometimes the listing agent measured it themselves. And sometimes it comes from a proper measurement done to a set standard.

These sources are not equally reliable. A developer brochure describes a floor plan before the building exists, and the finished unit can differ. An old record might have been measured under different rules years ago. A quick tape measure by a busy agent can miss corners, closets, or an odd angle.

In our experience, most listings in Surrey, Langley, and Abbotsford are careful, but "careful" still means different agents using different sources. That is exactly why two similar units three doors apart can show sizes that do not line up. The number is a starting point, not a settled fact.

What is the Residential Measurement Standard?

Many BC real estate boards ask agents to measure homes using the Residential Measurement Standard, usually shortened to RMS. RMS is a set of rules for measuring floor area the same way every time, so one listing can be compared to the next without guessing which method was used.

For a condo, RMS generally measures the interior liveable floor area, the space inside your unit that you actually live in. The point of a shared standard is consistency. If every unit in a building is measured to RMS, then price per square foot across those units means something, because you are comparing like with like.

The catch is that not every number on every listing is an RMS measurement. Older listings, private sales, and some presale figures may use other methods. So before you lean on a square footage number, it helps to ask a simple question: was this measured to RMS, or did it come from somewhere else? Your agent can usually tell you, and if the answer is unclear, that itself is useful to know.

Why does the strata plan show a different number?

Every strata building in BC has a strata plan filed at the Land Title Office. It defines the boundaries of each strata lot, the legal term for your individual unit. The strata plan often lists a size for your unit too, and it frequently does not match the listing.

The reason is boundaries. The strata plan measures your strata lot to a legal boundary, which in many buildings runs to the middle of the walls, or to another defined line, rather than to the inside face of the wall where you stand. Interior floor area, the way RMS often measures a condo, stops at the inside of the walls. Measure to the middle of the wall and you capture a bit more space, so the strata plan number can read larger than the interior number.

Neither figure is wrong. They answer different questions. The strata plan answers "what is the legal extent of this lot," and the interior measurement answers "how much floor am I living on." For the Land Title and Survey Authority records that define your legal ownership, the strata plan governs. For deciding whether your couch fits, the interior number is more useful.

Does the appraiser use a different number again?

When you get a mortgage, the lender usually orders an appraisal, an independent estimate of the home's value. The appraiser often measures the unit themselves, and their figure can differ from both the listing and the strata plan.

This matters more than most first-time buyers expect. The lender lends against the appraised value, not the price you agreed to pay. If the appraiser measures a smaller unit or values it lower than your offer, the lender may advance less money, and you would need to cover the gap. It does not happen on every deal, but it happens.

The practical takeaway is to know the real measured size early, not on closing week. If size is central to why you like a unit, and to the price you are paying, talk to your mortgage broker about how appraisal works before you write. A mortgage broker or your bank can walk you through what happens if an appraisal comes in low, so it is a plan rather than a surprise.

Why you should not overpay per square foot on an unverified number

Price per square foot is the shortcut buyers reach for when comparing condos. Take the asking price, divide by the square footage, and you get a number you can line up against other units. It is genuinely useful. It is also easy to misuse.

The trap is dividing by a figure nobody verified. If one unit's size came from a polished brochure and the unit down the hall was measured to RMS last month, comparing their price per square foot is comparing two different things. The "cheaper" unit per square foot might just have a more generous number on the page.

There is a second trap: price per square foot cannot see layout. A well-designed 850 square feet with an open plan and few hallways often lives larger than an awkward 950 with wasted corridor space. Floor level, exposure to light, noise, parking, and view all move real value and none of them show up in a size-based ratio. We have watched buyers pass on a smart smaller unit for a larger one that felt cramped the moment they walked in. The number said one thing; the space said another.

This is also where the building itself matters. A wood-frame versus a concrete condo can feel different at the same square footage because of ceiling height, sound, and wall thickness. Square footage is one input. It was never meant to carry the whole decision.

What a Fraser Valley buyer should actually check

Start by asking where the listing number came from and whether an RMS measurement exists. That one question sorts a verified figure from a copied one. If size is central to your decision, you can review the strata plan and compare it against the listing, and for a large purchase some buyers hire a professional measurement service for peace of mind.

Then look past the number. Walk the unit and picture your real furniture in it. Check the strata documents while you are at it, since size sits alongside the other things that shape the cost of ownership. The Form B information certificate tells you the fees, the reserve fund, and any levies, and those numbers affect your monthly budget as much as the floor area does.

Speaking of budget, remember that a bigger unit usually means a higher strata fee, because fees are often tied to unit size. So a few extra square feet can cost you every month, not just once at purchase. Our guide to the total monthly cost of owning a condo or townhouse walks through how those pieces add up. Square footage is one line in a longer story.

The bottom line for Fraser Valley buyers

Square footage in BC is not one official number. It is several numbers, measured by different people to different boundaries, and the version on a listing is a starting point rather than a settled fact. Know where it came from, treat price per square foot as a rough guide instead of a verdict, and let the way a unit actually lives carry real weight in your decision.

If you are weighing two units and the sizes do not seem to add up, book a low-pressure chat with the FRIVE team and we will help you read where each number came from. You can also browse current Fraser Valley listings and start comparing units with clear eyes. And for anything touching your appraisal, mortgage, or the legal boundaries on a strata plan, confirm the details with your mortgage broker and your lawyer before you commit.