Electric Radiant 128-239 sqft Floor Heating Cable by Heatizon Systems.
This system will heat floors for new or remodel construction and can be installed under Tile and Stone, or in a mortar bed under laminate, vinyl, or carpet. This cable allows to be installed around objects and with included strapping is easy to cover the desired square footage prior to installing the floor. At about 1/8″ thick, the heating element causes minimal floor buildup. The Heatwave Cable products offer a Limited Lifetime Warranty.
Heatizon has a calculator for figuring the square footage for the space:
Square Footage Calculator (new window)
Don’t forget to remove footage areas under toilets, counters and other areas you do not wish to heat.