The growth in building refurbishment works is creating a demand for suitable materials, retrofitting techniques and research. The differences between refurbishment of new-build projects and historical or valuable buildings are insufficiently recognized - mostly the buildings without further cultural preservation requirements are studied. This article covers the theme of retrofitting the historical buildings, when due to the valuable facade or other heritage preservation requirements only the inside insulation is allowed. The problems of moisture in brick wall construction, loosing space, etc. are discussed and method for selecting best insulation option is shown. The 5 modern insulation materials are selected, measurements are made and best alternative is found using TOPSIS method with grey numbers. (C) 2014 Elsevier B.V. All rights reserved.