Does an Ottawa heated mat go under tile or in mortar?

Heated floor mats in Ottawa tile installations go in the mortar bed, not under the tile as a separate layer. The mat is embedded in the thinset mortar, with tile installed directly on top.

How the installation works: The electric heating mat is unrolled across your prepared subfloor, then covered with a layer of thinset mortar. The tile is set directly into that mortar layer, which encases the heating cables and bonds everything together. This creates a thermally efficient system where the tile absorbs and radiates heat evenly across the surface.

Proper sequence matters significantly. The subfloor must be clean, level, and structurally sound before the mat goes down. Most installers apply a thin layer of thinset first, embed the mat into it, then apply another layer of thinset for the tile. The heating cables should never be crossed or bunched, and the mat must be fully encased in mortar with no air pockets — voids cause hot spots that can burn out the element prematurely.

In Ottawa's climate, heated tile floors are extremely popular in bathrooms, mudrooms, and entryways given our cold winters. A few Ottawa-specific considerations worth knowing: if you're adding a dedicated circuit for the heating system, an electrical permit is typically required through Ottawa Building Services. Your electrician and tile installer need to coordinate on this — the mat gets a continuity test before, during, and after tile installation to confirm no cables were damaged.

For tile selection, porcelain is the preferred choice over ceramic for heated floors because it's denser and conducts heat more efficiently. Large format tiles (12x24 or larger) are also popular since fewer grout lines mean a cleaner look and better heat transfer.

The thermostat sensor wire also gets embedded in the mortar between heating cables — placement of this sensor is critical for accurate temperature readings, so it shouldn't be an afterthought.

For a free estimate on heated tile floor installation, Ottawa Floor Install handles the full scope including coordination with your electrician. Request a quote and a contractor can assess your subfloor, layout and heating requirements in one visit.