A slab-on-Grade system is one of the most common radiant heating installation systems. It’s suitable for residential, commercial, and industrial structures. The system is built by attaching PEX tubing to the wire mesh and pouring concrete over it. Insulation should be placed under the slab to ensure that the heat doesn’t escape into the ground.
A thin-slab system is used to heat floors with a wooden frame. PEX tubing is attached to the floor, a 1.5" layer of gypsum or special concrete mix is poured over it. Weight of the slab should be considered when designing the flooring support structure.
A plate system uses aluminum plates to spread heat. Aluminum is an excellent conduit of heat and is light; allowing it to be a great substitute for concrete, especially in cases where concrete can’t be poured due to its weight. Plates can be installed either above-floor or below-floor. In above-floor installations, plates and tubing are placed between the sub floor and finish floor. In a below-floor plate system installation, tubing is placed into the joist cavities under the floor and is covered with aluminum plates, which are then stapled to the sub floor.
A Suspended tube system is installed by suspending tubing inside the joist cavity, and adding insulation underneath to avoid downward heat escape. Since, there is no direct contact between tubing and the floor, higher temperatures are required to increase the heat output. In some cases fins are attached to the tubing in order to increase the surface area of heat output.
A sandwich method of PEX tubing installation is identical to the plate system. Tubing is often laid between wooden sleepers and is covered by the floor finishing.
