What Ottawa building code requirements apply to heated floor wiring under tile near a bathtub?

Heated floor wiring near bathtubs in Ottawa must comply with strict ESA electrical safety requirements and Ontario Building Code regulations. The electrical work must be performed by an ESA-licensed electrician, with the heating elements installed at least 150 millimetres (6 inches) away from the bathtub edge, and the entire system must be protected by a GFCI breaker and inspected before the tile installation can proceed.

The proximity to water makes this one of the most regulated aspects of heated floor installation in Ottawa homes. The Ontario Electrical Safety Code requires that all electrical heating elements be kept outside the "bathtub zone" — a defined area extending 150 millimetres horizontally from the tub edge and up to the height of the shower head or 2.25 metres, whichever is higher. This means your heating mat layout must be carefully planned to avoid this restricted zone while still providing comfortable heated flooring in the rest of the bathroom.

All heated floor systems near bathtubs must be hardwired through a dedicated GFCI-protected circuit — plug-in systems are not permitted in bathrooms under the Ontario Building Code. The thermostat must be installed outside the bathtub zone, typically on a wall at least 1 metre from the tub edge. The heating cable or mat must be embedded in the tile adhesive or self-leveling compound, never installed loose under the subfloor where moisture could reach the electrical components.

ESA inspection is mandatory before the tile can be installed over the heating system. The electrician will test the system, verify proper GFCI protection, confirm the heating elements are undamaged, and ensure all clearances from the bathtub are met. Only after ESA approval can the tile installation proceed. This inspection typically costs $150 to $300 and must be scheduled in advance — failing to get the electrical inspection before tiling means tearing up your new tile floor to access the wiring for inspection.

The tile installation itself requires an uncoupling membrane rated for heated floors, such as Schluter Ditra-Heat, which protects the heating elements from tile movement while providing waterproofing. Ottawa's extreme temperature swings make this membrane especially important — it prevents seasonal subfloor movement from damaging the heating cables.

When you're ready to plan your heated bathroom floor project, you can browse ESA-licensed electricians and experienced heated floor tile installers through the Ottawa Construction Network directory to ensure both the electrical and tile work meet all code requirements.