Ardex K 15 Self-Leveling Underlayment
Premium self-leveller that flattens uneven slabs before any floor goes down, covering about 50 sq ft per 55 lb bag.
Free pickup in Markham (ready next business day) · GTA delivery $140
Specs
| Category | Subfloor Prep |
| Unit sold | 55 lb bag |
| Availability | Ready for Markham pickup next business day |
| Coverage | ~50 sq ft per bag |
| UPC | 709850804065 |
| Code | AR-K-15 |
How to use Ardex K 15 Self-Leveling Underlayment
- 1Prime the subfloor first — Ardex recommends Ardex P 51 on absorbent concrete (in this catalog) so the leveler bonds and doesn’t dry too fast at the surface.
- 2Mix Ardex K 15 with water per the bag instructions to a pourable, lump-free consistency using a drill and paddle mixer.
- 3Pour and spread with a gauge rake or trowel — it has about a 10-minute flow time, so work in sections you can pour and spread before it starts to set.
- 4It levels up to about 1/4" per pour and can be tapered to meet existing elevations at the edges of a repair.
- 5The floor is typically walkable in 2–3 hours.
- 6Before installing your new flooring: moisture-insensitive tile and stone can usually go down after about 6 hours, but every other floor covering (vinyl, laminate, engineered/solid wood) needs roughly 16 hours cure time — always confirm on the bag for the batch you bought.
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FAQ
How do I know if I need a patch compound or a full self-leveling pour?
Small gouges, seams, and low spots (under about 1/4") are a job for a patch/skimcoat compound. A subfloor that’s sloped, or has low spots across a large area, needs a self-leveling underlayment that pours and finds its own level. Ask us if you’re not sure which your floor needs.
How long before I can install flooring over it?
Cure time depends on the product and your new floor covering — check Ardex K 15 Self-Leveling Underlayment (55 lb)’s bag for the exact window, and always confirm before laying flooring over a fresh pour.
How much Ardex K 15 Self-Leveling Underlayment (55 lb) do I need?
Use the calculator on this page — enter your square footage and we’ll size the exact quantity, based on 1 bag covering about 50 sq ft.
Not sure which product you need?
Use our supplies calculator to get a full kit recommendation for your floor type and subfloor, or ask us directly.