How thick should your floor actually be? We checked every spec sheet we sell

Thickness is the first spec most people look at, and the one they trust most. It is also the number that tells you the least about how a floor will actually perform. So before repeating the usual advice, we went through our own catalogue to see what is really on the market.

We list 118,651 products. Of those, 37,972 carry a thickness figure. That is the honest denominator for everything below — this is a picture of what suppliers offer into Canada through us, not a survey of Canadian homes.

What the spec sheets actually show

The distribution is lopsided. One band dominates — 3–4 mm, at 13,301 products. Everything else is spread thinly across the rest of the range.

3–4 mm is the range most rigid-core vinyl is built in, which is the likeliest reason that band is so crowded — though the catalogue records what is listed, not why. The practical consequence is the same either way: if you shop by thickness alone, you will spend most of your time inside one crowded band, comparing products that are near-identical on the spec you are looking at and very different on the specs you are not.

What thickness controls — and what it doesn’t

Overall thickness controls how a plank behaves as a piece of structure: how rigid it is, how much subfloor unevenness it can bridge, how it sounds underfoot, and how much height it adds at the door. It does not control how long the surface lasts. Every category has a different number for that, and it is never the big one on the front of the box.

This is the single most useful thing to take from the data. Two vinyl planks can both be 4 mm thick and carry completely different wear layers. They will not age the same way, and in a hallway with a dog you will know which is which inside two years.

The height problem nobody plans for

The place thickness actually costs you money is not the invoice — it is the doorway. Finished floor height is the plank plus the underlay plus any levelling compound or adhesive bed beneath it. All of it is additive, and all of it is easier to plan than to fix.

• Interior doors. Measure the gap under every door before you order. A door that clears a rug today may not clear a thicker build-up.
• Transitions to rooms you aren’t redoing. A step change needs a reducer, and a reducer in a hallway is a trip point.
• Stairs. Stair nosings are made to suit a specific floor height. Change the flooring thickness late and the nosing you ordered no longer sits flush.
• Appliances under a counter. Raising a kitchen floor can trap a dishwasher under the countertop. Check that clearance before, not after.
• Floor vents and sliding doors. Both are set to the old height and both need adjusting to the new one.

None of this is a reason to buy the thinnest floor you can find. It is a reason to settle the total build-up early and design around it, rather than discovering it on installation day.

When thinner is the right answer

There is a persistent assumption that thicker is safer. Often it is. But the cheaper option is genuinely the correct one more often than the industry likes to admit:

• Over a flat, dry, sound slab, a thin glue-down floor is bonded along its whole length. No joint is carrying load, so the rigidity you would be paying for is doing nothing.
• Over radiant heat, a thinner floor conducts better. A thick, insulating build-up fights the system you already paid for.
• In a condo with a finished-floor-height rule, thickness is a constraint before it is a preference.
• In a rental or a flip, a mid-range floor on a properly prepared subfloor will outperform a premium floor on a bad one.

The reverse is equally true. If your subfloor has gentle waves you are not going to grind out, a thicker rigid plank will bridge them where a thin flexible one telegraphs every last one.

How to use the thickness filter here

Most of our catalogue carries no thickness value at all — trims, adhesives, underlays, cleaners and accessories have no meaningful plank thickness, and some manufacturers simply do not publish one. So use the filter to narrow, then do the real comparison inside the shortlist on the spec that governs wear. If a product you like has no thickness listed, ask us; it is usually on the manufacturer’s technical sheet even when it is missing from the feed.

The short version

• Thickness is a structural spec, not a durability spec.
• 3–4 mm is the most crowded band in our catalogue, at 13,301 products, so that is where the comparison work has to get more careful, not less.
• Wear layer, veneer thickness and abrasion rating decide how the surface ages.
• Add up the whole build-up — plank, underlay, levelling — before you order, then check your doors.
• Thicker is not automatically better. A flat subfloor beats an extra millimetre.

Shop what this guide covers

• vinyl planks (LVP and SPC) — the crowded 3–4 mm band, where the wear layer does the deciding.
• underlayment — the second number in your build-up, and the one people forget.
• mouldings and trims — reducers and nosings, sized to the height you end up with.
• self-levelling compound — cheaper than buying thickness to bridge a wavy subfloor.
• Why floor thickness matters less than your subfloor — the argument this article is the first half of.