Floor heating system including membranes that are configured to be joined together to house a heating cable, and flooring underlayment including such membranes

A floor structure comprising:

• a subfloor;
• floor tiles;
• a base membrane configured to be installed between the subfloor and the floor tiles to allow movement of the floor tiles relative to the subfloor, the base membrane including a base layer and a plurality of studs projecting from the base layer, the plurality of studs having free ends that define pockets therein;
• and
• a cover membrane configured to be coupled to the base membrane to form a flat surface for supporting the floor tiles, the cover membrane including a cover layer and a plurality of studs projecting from the cover layer, wherein the plurality of studs on the cover membrane are configured to fit within the pockets in the plurality of studs on the base membrane to couple the cover membrane to the base membrane.

A method of installing a floor structure, the method comprising:

• placing a base membrane onto a subfloor, the base membrane including a base layer and a plurality of studs projecting from the base layer, the plurality of studs defining a plurality of pockets therein;
• coupling a cover membrane to the base membrane by inserting a plurality of studs on the cover membrane into the plurality of pockets in the base membrane to form a flat top surface;
• and
• installing floor tiles on the flat top surface formed by the cover membrane.