Facade and building shell

The building shell consists of a combination of different materials, characterised by different thermal expansion coefficients. Exposure to external agents, such as sun, rain and wind, causes dimensional changes, which are small when taken out of context but very important in the overall behaviour of the building. Other types of stress may derive from vibrations induced by sound waves, traffic or simply all those settlements to which every building is subject: a continuous and imperceptible movement, invisible to the naked eye. A rigidly constructed connection could crack, allowing air, water and chemical agents to penetrate into the building and cause it to deteriorate. In this context, therefore, thermal expansion is certainly the aspect that must be taken into the greatest consideration when joining the parts that make up the building shell, and it must be adequately supported by making elastic sealing joints.