Heatloss through a concrete slab - a comparison of edge beams

Abstract: Of all the heat that is supplied in an average house in Sweden, about 15% of the heat leaks out through the foundation and the ground. A foundations task is to provide a solid base for a house while it should also keep the heat in the house. This report deals with the foundation concrete slab, where the focus is largely on comparing three different types of edge beams with respect to thermal bridges and energy consumption. This work has been performed in collaboration with Fiskarhedenvillan which is one of the largest house suppliers in Sweden. Fiskarhedenvillan are constantly working with reducing the energy consumption in their houses and now wish to obtain a better insight into how the choice of edge elements in the slab can affect this. To get a better understanding of how heat transfer works the report begins with a theoretical part. It deals with how heat conduction, radiation and convection works. The theoretical part also deals with foundations, thermal bridges, concrete slab and edge beams in general. The edge beam solutions mentioned in the report are: • U‐min grund, energy‐efficient • Leca edge element • Dorocell, L‐element Using the computer program HEAT2, a simulation of the edge beams has been made to obtain different values of thermal bridges. These values were then used to calculate how the choices of the edge beams affect the total energy consumption in a house