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Sizing and running costs

The two questions we're asked most: how much heat do I need, and what will it cost to run?

Choosing output

Typical outputs by floor type

Output is measured in watts per square metre (W/m²) of heated area. Higher output warms up faster and handles more heat loss. The floor covering sets the upper limit.

Application	Typical output	Usual system	Notes
Bathrooms and ensuites, tiled	150–200 W/m²	DEVImat under tile	200 W/m² suits cold slabs and rooms with large windows.
Kitchens and living areas, tiled or stone	100–150 W/m²	DEVImat or DEVIflex 18T	Leave out areas under fixed cabinets and islands.
Floating timber, laminate, engineered boards	up to 100 W/m²	DEVIcell Dry + DEVIflex 10T	Floor surface usually limited to about 27 °C. Check the flooring maker's limit.
Carpet and vinyl	100 W/m²	In-screed cable	Check the tog rating of carpet and underlay.
Driveways, ramps, paths	250–400 W/m²	DEVIsnow 30T	Sized to climate. Controlled by temperature and moisture sensors.
Roofs and gutters	18 W/m @ 10 °C	DEVIiceguard	Self-limiting. Sized per metre of gutter and downpipe.

These are starting points, not a design. We confirm output against heat loss, subfloor, insulation and the finished floor on every quote.

Running cost estimator

What will it cost to run?

Enter your room and tariff. The estimate assumes the thermostat cycles the heating on and off once the floor reaches temperature.

Estimated cost

$0.45

per day

Connected load: 0.75 kW
Energy per day: 1.50 kWh
Per season: $67.50
Maximum per day, heating flat out: $0.90

An estimate only. Actual use depends on insulation, room temperature, floor build-up and tariff. Off-peak or time-of-use tariffs can lower costs.