1. Inventory
Our property is a single-family house built in 1971.

2. Problem definition
The house initially had a maximum of 10 cm of insulation that was not continuous. This led to a high heat loss in winter and consequently to high additional costs. In addition, the small number of windows in the roof area resulted in insufficient lighting of the attic.

3 Implementation
A U-value of 0.14 W/m²K was set for the insulation, so that the requirements of the Building Energy Act (GEG) were not met. For this, insulation made of cellulose and wood fibre was laid and fixed with wooden boards. The installation of the thick insulation layer was made possible by raising the wooden rafters by 8 cm. With the subsequent replacement of the roof tiles, the roof was also given a new look externally. In addition, the stone was sealed so that no moisture can penetrate into the house through it.
The final step was the installation of two new Vellux windows, which provide more light in the attic.
With these measures, a well-insulated house was created, which at the same time enjoys the benefits of air-permeable insulation and leads to a pleasant indoor climate.