Navigation and service

Retrofit insulation of the cellar ceiling

diese Seite auf Deutsch

KellerdeckeSource: Fotolia

The insulation of the ceiling to unheated cellar rooms from below is a simple and generally cost-effective measure to improve the energy quality of a building. A personal contribution by the owner is possible. The prerequisites for the measure are accessibility and sufficient remaining room height.
An alternative is insulation of the upper side of the ceiling, i.e. through alteration of the floor construction in the storey above.
The achieved energy cost savings of a thermal insulation of a cellar ceiling also depend on the initial state.

U-values of selected constructions

Among other things, the energy performance of cellar ceiling depends on the existing construction. Depending on the age of the building and on the region, a variety of constructions can be found. The age of the building alone only allows a limited inference of the energy quality.

The following table shows exemplary U-values of frequent constructions. Cellar ceilings are often designed as solid structures.

Cellar ceiling
KonstruktionBaujahrBauteilaufbauU-Wert
W/(m²·K)
Timber beam ceilingbis 191816 cm timber beam/puddle clay, 2 cm shelves, 2,5 cm floor board1,13
Vaulted ceilingbis 194812 cm vaulted ceiling solid brick, 12 cm flooring sleeper/filling, 2,5 cm floor board1,10
Concrete ceiling1919 - 4916 cm concrete ceiling, 6 cm bonded screed1,94
Concrete ceiling1949 - 5715 cm concrete ceiling, 2,5 cm insulation, 1cm floor screed0,93
Concrete ceiling1969 - 7814 cm concrete ceiling, 4 cm insulation, 4 cm floating floor0,68
Concrete ceiling, insulated*refurbished15 cm concrete ceiling, 4 cm insulation, 4 cm floating floor, 12 cm insulation0,22

Source: [Source: Zentrum für umweltbewusstes Bauen e. V.
* own calculations (solidar planungswerkstatt using www.u-wert.net)]

This Page

© Copyright by BBR. Alle Rechte vorbehalten. - 2013