Natural Stone

Our approved methods of rehabilitation

  • Repair of natural stone by inserting quadratures or by application of restoration mortar
  • Strengthening sand and surface layers of minor solidity
  • Joint filling of structures with natural stone
  • Deep Joint filling in dry spray method for structures of natural stone
  • Injection of cracks with filling material such as reaction resin, cement suspension, cement lime or other suitable filling material
  • Cleaning of facades made of mineral construction materials

Quality with a reinstatement design from WELS

  1. Survey and documentation of damages
  2. Testing at the surface:
    • Quantitative Assessment of harmful substances (Chlorides, Nitrates, Sulfates)
    • Assessment of moisture and hygroscopicity moisture absorption at drilled cores:
    • Assessment of the type of natural stone and re-points
    • Assessment of capillary water absorption
    • Assessment of sorption moisture
    • Assessment of pore volume
    • Testing of swellable clay and assessment of the hygric moisture expansion and shrinkage
    • Assessment of conservation by using standard preserving agents
  3. Recommending a reinstatement concept of rehabilitation and conservation measures due to preservation orders.

“Die Burg” – rehabilitation of a facade


“Kaiser-Wilhelm-Gedächtniskirche” – rehabilitation of a facade


“Rehabilitation of „Heiliger Michael“, Embassy of Vatikan in Berlin

Image: Copro-Gruppe

© wels GmbH 2019