Useful tips to make your loft conversion an all-round success

Especially under the roof, there is an enormous potential of extra living space waiting to be unlocked by a loft conversion. Our expert explains what needs to be considered in planning a conversion project and what to look out for when choosing products.

Tip 1: Check the building fabric and apply for funding

First, you should thoroughly check the existing building fabric. How stable is the top floor ceiling? What condition is the roof truss in? Is the roof covering watertight and will it last a few more years? Interested homeowners are best advised to clarify these and other questions with the respective experts. An (interior) architect, a civil engineer or a building surveyor can provide valuable assistance. Hiring a specialist also makes sense because a loft conversion usually requires the coordinated work of several trades.

Good to know: If you use the services of an energy consultant, the German Federal Office for Economic Affairs and Export Control (BAFA) will subsidize this by up to 80 percent. The BAFA also provides funding for individual measures on buildings that improve their energy efficiency. For the energy optimization of the building envelope, including roof insulation and the installation of new windows, 15 percent of the eligible costs are currently reimbursed.

Tip 2: Decide on the future use of the new living space

After checking the building fabric, the next step is planning. How will the future living space under the roof be used? As a home office or as a separate living unit complete with bathroom and kitchen? In this case, you need to prepare and install the supply lines for electricity, water, sewage and possibly also telephone and internet. Furthermore, you need to clarify whether the existing space and the incident light under the roof are sufficient or whether windows (don’t forget a shading device!), dormers or a raised knee wall are required. Attention: All measures that change the external appearance of the building are usually subject to approval.

Tip 3: Make sure there is good insulation and sufficient ventilation

The first step in an attic conversion is the proper preparation of the top floor ceiling. This is done, for example, by installing a dry screed with levelling fill. At the end of the conversion, the actual floor covering can be laid. The installation of thermal insulation is indispensable when converting the attic. This not only keeps the heat in during the winter, but also the heat out in the summer. Roof insulation, however, is best left to a professional roofer. Along with the insulation material, you also need to install a vapor barrier to prevent thermal bridges where humidity condenses and ultimately causes mold growth. Furthermore, connections to roof windows (e.g. skylights) and penetrations (e.g. for a satellite dish) must be tightly sealed. In addition to thermal insulation, you need to ensure that the attic can be adequately ventilated (e.g. by cross-ventilation) to provide a good indoor climate. If roof windows are already in place, check whether a replacement makes sense so that the insulation effect is not wasted. If necessary, also have the window reveals insulated.