Throughout the centuries, the facade of buildings, especially churches and representative buildings, has played a special role. The first glance of the observer is at the robe of a house. The decorative elements used also make it possible to read off the stylistic epoch and to make a historical classification.
The facades or building sculptures made of stone are constantly exposed to the weather or other stresses. The term stone is wrongly assumed to be a hard and robust material. Many natural stones have a soft structure or react sensitively to temperature fluctuations such as marble. Specially trained stone restorers are required to maintain the charm and attractiveness of the stone.
The Stone Conservation and Stone Restoration Department
Stone conservation and stone restoration is a form of restoration in itself and includes all areas in which stone is used. This can take the form of facade designs, floors, smaller sculptures or large sculptures or reliefs. The concept of stone as a building material can also be understood more broadly. Natural stones, marble, terrazzo and mosaic floors as well as ceramic works are also included. In addition, the basic material is not always available in a transparent version. These are often coloured or integrated into other design variants, for example in a wall painting. For a stone restoration the knowledge of different craft techniques and material compositions is therefore absolutely necessary. Experts from the fields of architecture, archaeology and art history often work closely together.
What distinguishes a stone restorer from a stonemason or stone sculptor?
There are two ways of training to become active in the field of restoration. The training in the handicraft with the qualification of specialist craftsman for monument care presupposes the learning of a handicraft occupation. This includes the profession of stonemason or stone sculptor. Both create objects out of stone. These stand as art objects for themselves or upgrade a building. The stone restorer, on the other hand, does not create objects, but is responsible for their preservation and conservation. His training takes place by studying restoration at a technical college or university. A restorer does not work in the craft but freelance. The stonemason can also become active in restoration with additional training as a specialist craftsman for monument conservation.
Procedure of a stone restoration
At the beginning of every restoration there is a detailed examination and analysis of the object. This can be done on site, e.g. in the area of monument conservation or in the workshop, if the object is movable. The restorer examines the original material, other components used, any colour treatments, the time of origin and the manufacturing process. From this, he can determine the origin of the damage that has occurred and the necessary restoration procedures. He writes down his findings in a state analysis. He then carries out the restoration and documents each work step. Restoration includes cleaning, the consolidation of weathered stone surfaces as a conservation measure and, if necessary, the reconstruction of lost objects. In the field of building restoration, procedures for draining and heating historical rooms play an important role. If possible, all processes are also digitally documented.
Which damages occur frequently?
Facades made of stone are exposed to various environmental factors. Rainwater penetrates into small cracks and the pores of the stone and can cause damage in frost. The intensity of the sun also leaves traces, especially in coloured designs. The quality of the air has deteriorated significantly in recent decades, especially in urban areas. The density of pollutants has increased and this has an effect on the material substance. Environmental toxins are also brought to the material by acid rain. In many cities, effective pigeon protection is still required to protect sculptures and figures made of stone.
Floors made of marble or terrazzo are not only exposed to mechanical stress, but they also react sensitively to changes in temperature or unsuitable cleaning substances. The surface of the materials becomes permeable to water, dirt or microbial spores. First of all, the aesthetic effect of the surface is lost because it loses its gloss or smooth feel. This is followed by a deeper destruction of the substance. Ingredients can break off or break out. Then it is also the task of the stone restorer to reconstruct lost parts and add them to the object.
Do you have a historical stone object and would like a restoration?
In the section of stone sculpture and stone architecture on our website, you as the client can see a list of references of the restorers registered with us. You can also find a suitable expert in your area via our directory of restorers and our search by area.
If you are interested in the restoration of stone objects, stone sculpture and stone architecture and are looking for an internship, training or further education, then we offer a lot of detailed information in our job exchange, as well as in the subject area of education and studies. Furthermore, we also provide basic information on the job description and the training to become a restorer.
Stone sculptures and stone architecture