Energy consumption data and thermographic images provide the first concise indications of the necessary building renovation measures.   

Before the refurbishment begins, a comprehensive inventory and evaluation are necessary to carry out the costly construction measures in an economically justified manner.   

With superficial renovation, money and personal contribution are wasted. The building envelope is the starting point for the evaluation.   

The basement masonry is exposed. A large proportion of all basement floors have construction defects in the area of the outer walls. After exposing the basement masonry, it can be clearly seen that water from outside can penetrate the building through the joints of the masonry. Roots of trees and bushes have penetrated the masonry. Rainwater seeps downwards in the area of the outer wall and additional dammed water penetrates through the masonry and collects in the basement rooms.   

The base of the building consists of quarry stone masonry. With its dense structure, it shows cracks only on the surface. Moisture penetrates deep into the masonry through cracks in the area of the mortar joints and already broken out joint mortar. In winter, the penetrated moisture freezes in the mortar joints and thus impairs the load-bearing function of the masonry.   

The exterior masonry of the ground floor and attic consists of double-shell brick masonry. The south and east facades are plastered with a lime-cement mortar on which natural stone chippings have been applied. The plaster is heavily soiled. Due to different settlements in the area of the foundation base, cracks lead from the foundation via the natural stone base into the first floor masonry up to the window sill.   

The north and west facades are shifted. The structure of the slate is considerably damaged by rain, frost and immissions. Moisture penetrates through the slate cladding into the wooden boarding underneath, which is rotten in many areas, and from here the moisture penetrates into the masonry behind the boarding and also permeates the interior plaster and wallpaper. A renovation of the slate façade is not advisable.   

The windows of this building show that improper installation, insufficient and unprofessional maintenance have led to rot. Colors have partly flaked off. Water penetrates under existing layers of paint, this leads to rotting in many places of the wooden windows.   

The roof is exposed to the weather conditions in a special way. In some rusted areas of the sheet metal roof, water penetrates into the underlying roof construction, walls and ceilings.