Updated October 2026. Greater Toronto Area rates in Canadian dollars, before HST.
Short answer: floor preparation runs $1 to $3 per square foot for general work, $2 to $4 for concrete levelling, and up to $5 on a badly out-of-tolerance slab. On a typical GTA job, prep is 15–30% of the total — and it is where most quotes either hide money or leave it out entirely.
Prep is the part of a flooring quote homeowners question most, because it is invisible once the floor is down. Here is the arithmetic behind it, with the actual material prices and the City of Toronto disposal fee, so you can check whether a quote is fair.
What prep costs, in ranges
| Work | Cost per sq ft |
|---|---|
| General subfloor prep | $1–3 |
| Concrete levelling (self-levelling compound) | $2–4 |
| Plywood underlayment over existing subfloor | $2–3 |
| Heavy slab remediation, badly uneven concrete | up to $5 |
Levelling should be priced over the area that actually needs it, not the whole room. A quote that applies $3/sq ft across 700 sq ft when only 200 need levelling is overcharging by roughly $1,500.
Self-levelling compound: the bag math
This is simple arithmetic any contractor can show you, and almost none do.
A 50 lb bag of self-levelling compound covers roughly 24–25 square feet at 1/4” thickness — Ardex V 1200 publishes 25 sq ft per bag at that depth. So at a 1/4” average pour, budget one bag per 25 square feet of the area being levelled.
A 340 sq ft basement floor therefore needs 9 to 10 bags. GTA contractor quotes posted on TrustedPros have run roughly $65–80 per bag installed on small jobs, which covers the material, the primer, the mixing and the labour. That puts a 340 sq ft level-out somewhere around $600–800.
If a quote says “levelling — $2,400” on that same floor, you now have a specific question to ask: how many bags, and at what depth?
Plywood underlayment: the sheet math
Where the subfloor is wood rather than concrete, a plywood overlay is often cheaper and faster than levelling compound.
A 4×8 sheet covers 32 square feet. Home Depot Canada currently lists 1/4” sheets from about $40.98 (Metrie sanded pine) to $59.98 (RICHPLY 6mm fir). That works out to $1.28–1.88 per square foot in material alone, before fasteners, cutting and labour — which is exactly why installed plywood underlayment lands at $2–3 per square foot.
The trade-off is height. A plywood overlay raises the floor by its own thickness plus the finish flooring, which can mean doors need trimming and transitions need rethinking. On a basement slab it is usually the wrong answer anyway, because it traps moisture against the concrete.
Removing the old floor
| Existing floor | Removal per sq ft |
|---|---|
| Carpet and underpad | $0.30–0.80 |
| Carpet, general | $0.50–1.50 |
| Hardwood, laminate or vinyl | $1–3 |
| Ceramic tile | $2–5 |
Ceramic is the outlier because it rarely comes up cleanly — the thinset stays bonded to the slab and has to be ground off, which is slow, dusty work that often reveals levelling problems underneath.
Disposal: the number nobody quotes
Old flooring is heavy, and it has to go somewhere. City of Toronto drop-off depots charge $189.86 per tonne — billed at $1 per 5.27 kg, with a $19 minimum covering the first 100 kg and a $40 minimum deposit before dumping. Loads over 20 kg are charged on full weight.
Private junk haulage runs $100–250 per load. For a basement’s worth of carpet and underpad, one load is usually enough; a ceramic tear-out can be several.
This is a published municipal fee, not a contractor’s invention. If disposal appears as a line on your quote, that is where the number comes from.
When levelling is not the answer
Three situations where spending on compound is the wrong call:
- The slab is wet, not uneven. Levelling compound does nothing about moisture. If the slab tests above 75% relative humidity under ASTM F2170, the fix is a moisture barrier or a different product — not a flatter wet floor.
- The dip is small and local. ASTM F710 calls for flatness within 3/16” over 10 feet. A single shallow low spot is a patching job, not a pour.
- You are going floating, not glue-down. A click floor over a quality underlay tolerates more deviation than a glued one. Levelling an entire room to glue-down tolerance when the spec is floating is money spent for nothing.
What you can honestly skip
Not every floor needs every step. On a sound, flat, dry plywood subfloor in a 2010s house, prep may genuinely be a sweep and a few screws. We will tell you when that is the case — there is no margin in selling work a floor does not need, and a contractor who quotes full levelling on every job is not inspecting, they are guessing.
What should never be skipped below grade is the moisture test. It takes minutes, and it is the difference between a floor that lasts and a warranty claim that gets denied.
Getting prep priced properly
A good prep quote names the work, the area and the method — not just a lump sum. Ours breaks out levelling, removal and disposal as separate lines so you can see each one against the numbers above. We quote free across the GTA, including Toronto, Mississauga and Brampton.
More on what we do and why on the floor preparation page, or see what a full basement floor costs with prep included. Request a free quote or call 416-889-8273.