Installation

There are three choices of installation:

1. Slab-on-grade system: One example of a slab-on-grade system is PEX tubing attached to a wire mesh or clipped onto rigid Styrofoam insulation. Concrete is poured over the piping or tubing at the ground “grade” level. The slab must be insulated from the exterior side of the floor all the way to the slab edges.

2. Thin slab system:
1. The floor heating tubing is fastened above the subfloor and is covered with lightweight concrete or selflevelling gypsum cement underlayment. The floor ranges in thickness from 3.2 to 3.8 cm (1.25 to 1.5 in).
2. Another version is to sandwich the tubing between the subfloor and the finished floor. This raises the floor only 1.3 cm (1/2 in). There are a variety of new underlayment panels that hold the tubing in place and incorporate aluminum transfer plates to improve heating performance.

3. Dry or “Plate” system: Tubing is attached to the underside of the subfloor, also known as a belowdeck or joist space dry system. In cold weather climates, tubing should be attached with aluminum transfer plates and both well insulated for improved performance. Without the insulation, the warmth will disperse into the basement. It is also possible to have an abovedeck dry system, where heat transfer plates are supported by sleepers.

It is recommended that a licensed contractor install the heating system.

Costs

An approximate cost of an installed hydronic radiant floor heating system by a licensed mechanical contractor can range from $600 to $800 per approximately 100 square feet. This cost can be more or less depending on specific heating requirements and energy efficiency results. In addition to the heating system, a mechanical ventilation system is required in the house.