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The heat passage coefficient is specified by the so-called u value, previously referred to as the “k value”. It is used to evaluate the transmission heat loss of a component. The u value gauges the heat flow per m² of surface area and temperature difference in Kelvin.

The smaller the u value, the better isolated the wall or window is.

Why install underfloor heating? There are numerous reasons for the rising use of this type of heating system. In contrast to conventional systems, underfloor heating transfers mild and uniform heat across the entire floor surface, thus giving the occupants a greater sense of well-being.

Underfloor heating systems are operated at energy-saving low temperatures. The technical aspects behind this can be easily explained as follows: Because the entire floor functions as a large heating surface, these systems require only reduced heating water flow temperatures (approx. 30 °C). As the heat is transferred evenly from the floor throughout the room, a room heated to only a temperature of 20 °C will be perceived as being as warm as a room heated to 22 °C in a conventional way. All in all, this means double the savings. The overall low temperature in the system minimises heat loss. This saves energy as well as costs. Your “personally perceived sense of well-being” also minimises costs, since lowering the room temperature by 1 °C amounts to energy savings of approx. 6%.

The floor covering should already be taken into account in the planning stages of the heating system. When choosing the type of floor covering, products which readily transfer heat, e.g. tiles, are recommended to keep the required maximum flow temperatures as low as possible. This allows for the greatest possible energy utilisation. If the system is installed in a professional manner, the efficiency of the heating system can be maintained even if a different type of floor covering is later used.

Generally speaking, you can select nearly any type of floor covering.

Suitable are:

• Ceramic tiles
• Natural or concrete stone
• Textile coverings
• PVC
• Linoleum
• Laminates
• Parquet