Example of calculation in direct heating

Output for a new and well insulated house 40-60 W/m².

We have a 20 m² kitchen witch floor is covered with tiles.

20 m² * 60 W/m² = 1200 W.

Cupboards etc. cover 7 m² of the floor area.

Surface to install the cables: 

20 m² - 7 m² = 13 m².

The required installed output should be 30% higher than the calculated heat loss:

1200 W * 1,3 = 1560 W.

We choose the corresponding or the nearest resistance.