Builders’ joinery is a very important part of constructing high quality prefabricated buildings with excellent insulation. In the past, this was considered a weak link in the building’s thermal envelope. With the development of manufacturing technology, builders’ joinery has adopted a completely new meaning in an energy-efficient construction. It was proven for the Slovenian climate zone that properly planned installation of modern builders’ joinery has a positive effect on the energy balance of the whole building. Guidelines for the installation of the builders’ joinery dictate an airtight installation, which leads to lower heat losses and prevents the ingress of moisture into the construction. During the hot summer months, when the sun shines the brightest, the house needs to be protected from overheating. This is achieved most effectively by shading the glass surfaces. The most effective passive shading of glass surfaces is achieved with the help of the building’s layout or the proper planting of trees. We may also provide active shading through the use of external shade (such as venetian blinds, roller shutters, shutters, and roller blinds), which you can regulate yourself, or the smart house system can automatically ensure optimal shading.