How to Select Heating Cable?
Heat Loss and Demand
Radiant heating installations are normally designed to cover the heat loss and provide full heating. In new and properly insulated buildings, the transmission losses are normally in the range of 60-80W/m2 (5.5 - 7.5 W/sq.ft.)
In old or poorly insulated buildings the installations are normally based on an installed load of 80-100 W/m2 (7.5 - 9.0 W/sq.ft.) building area. When necessary a full heat loss calculation should be performed in accordance with local requirements.
The heat output required for a floor warming system ranges from 60 W/m² to 100 W/m² (5.5 - 9.0 W/sq.ft.), depending on the floor's insulation, thickness, and surface material being used (ie. tile, wood, carpet, etc.).
In order to select a heating cable that suits you best, we have to determine what is the net heating area first.
How to Estimate the Square Footage of Under-Floor Heating Cables
Please keep in mind that our factory made heating cables can not be cut or modified on site. Plan the cable layout in advance. Don't oversize the room -> Don't forget to deduct the area of any fixtures in the room! (ie. toilet, sink, shower, kitchen island)
Calculating the Heat Output
For general floor warming purpose, a output of 10 Watts per sq ft should be sufficient. For the bathroom illustrated above, net heating area is 47 sq ft,
47 sq ft x 10 Watts/sq ft = 470 Watts.
A 500 W heating cable will be perfect for this application.
WARNING: HEATING CABLES CANNOT BE CUT UNDER ANY CIRCUMSTANCES.