The article deals with the historic buildings and their insulation. It is generally known that classical thermal insulation of walls from the outside is not permissible due to the cultural value of historic facades. Compared to external insulation solutions, the implementation of internal insulation is more technically complex and faces several risks. In the article is devoted the chapter which deals with the aim of the application of internal insulation in historic buildings. There are mentioned risks associated with the application of internal insulation, which are related to the thermal-humidity behaviour of the structure. One chapter is devoted to faults that may occur after the application of internal insulation. These disorders have a building-physical character and also affect the hygienic criteria of the building. The larger chapter deals with insulating materials suitable for the purposes of interior insulation of historic buildings. The results of a case study from Dublin and Košice are also presented, where the thermal-humidity behaviour of selected thermal insulation materials was investigated. The results of moisture content and surface temperature before and after application of insulating materials are compared.

Main topic of the article speaks about historic building renovation in Košice. Nowadays, the building is in use as puppet theatre. The theatre suffers from various disorders caused by humidity. The envelope of building has been renovated several times, however, over time, the faults return over and over. The article can be divided into two parts. The first one presents the results of moisture analysis of the support wall. The samples from the facade probes were evaluated by gravimetric method. The second part of the article discusses the interior insulation of a historic building. Internal insulation is one of the solutions to reduce heat loss of historic buildings. The use of this type of insulation brings risks that affect the thermal-humidity behaviour of the perimeter structure. These risks are assessed using a simulation model. In addition to the risks, the impact of the insulation on the original wall structure and the impact on the indoor environment were also assessed. Based on the simulation results, we can assess whether the restoration approach is appropriate in this specific case of using insulation. The study shows that the initial humidity of the perimeter wall structure is an important factor for internal insulation. Before applying the internal insulation, it is necessary to examine the moisture and material properties of the masonry.

The paper examines possible solutions for the use of internal insulation in listed buildings. Massive thick walls of historic buildings represent large heat losses and the use of thermal insulation materials from the inside is a possible solution to increase the energy efficiency of historic buildings. However, the use of thermal insulation from the interior is accompanied by a number of risks associated with condensation, mould growth and damage to the perimeter structure. It is necessary to perform dynamic simulations to verify the thermal-humidity behaviour of the structure. The article describes materials suitable for the purpose of internal insulation, their advantages and disadvantages and a description of dynamic simulations by which their effects on the thermal-humidity behaviour of the perimeter wall of a historic building are assessed.