Underfloor heating: Make an informed choice!

Underfloor heating systems consist of extruded polystyrene boards, reflective foil, and water pipes. If you plan to install hardwood flooring on top, you’ll also need a layer of nylon mesh, and finally, a heating boiler.

High-quality XPS boards generally have good load-bearing capacity and feel springy when pressed; poor-quality ones usually leave a dent when pressed. When selecting XPS boards, try to choose ones that are at least 2 centimeters thick. If they are too thin, they won’t bear weight well, and there may be a risk of floor sagging or tile cracking during future use. Additionally, they won’t provide good insulation. You can shine a light through the XPS board; if the light passes through evenly, it indicates better environmental performance.

The reflective film is installed on top of the extruded polystyrene board. Its primary function is to direct heat upward, acting as a heat conductor. Since it is buried underground and cannot be replaced or repaired, it is best to choose a thick aluminum reflective film for greater durability.

Above the reflective film, the underfloor heating pipes are laid. Currently, the most commonly used underfloor heating pipes are made of PE material, which is divided into two series: the PERT series, with a maximum temperature resistance of 70°C; and the PEX series, which is further subdivided into three categories: A, B, and C. For residential use, the A and C types are typically chosen, as they can withstand temperatures up to 110°C and are generally more expensive. When selecting pipes, ensure the wall thickness is 2.0 mm or greater to guarantee sufficient pressure resistance. Pipes should be secured with specialized clamps; use double clamps at bends and secure straight sections every 40 to 60 centimeters. The spacing between pipes is generally around 20 centimeters, and there should be no joints in the middle.

The component above the pipes is the manifold; whenever possible, choose one made of pure copper. The number of manifolds installed is generally determined by the heating area. Each heating circuit should ideally cover no more than 15 square meters to ensure proper heating performance. The length of each circuit’s piping must not exceed 75 meters. It is important to note that you should adjust the spacing to keep the length of each circuit as consistent as possible. This prevents water from being drawn disproportionately from a single circuit, which could result in localized areas remaining cold.