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Video: Saved The Face

A listed residential building in Weil der Stadt was to be refurbished as much as possible and existing building defects removed. However, the street facade had to be preserved and did not allow any profound changes to the existing building structure. Dr.-Ing. Günter Glock, Baumit In accordance with the new Energy Saving Ordinance (EnEV), which entered into force on October 1, 2009, an exceptional application for partial renovation had to be submitted to the responsible building authority for the monument created between 1906 and 1908. After the application was approved, the renovation measures were carried out: the roof, the windows, the back of the building and the building services were replaced. The street facade was preserved in its original structure. Initially, interior insulation measures were considered,which, however, were not carried out in the later concept phase due to building physics reasons. Due to the overall energy planning and the monument conservation requirements, only the courtyard facade was available for energy-related repairs using a thermal insulation composite system (ETICS). The old plaster was so badly damaged that a pure plaster renovation made no sense economically or technically. The use of a thermal insulation composite system was therefore the only economically sensible solution, since it was also able to repair the cracks. Samples that were analyzed in the plaster manufacturer's building materials testing laboratory made it clearthat the complete base up to a height above the first row of windows was heavily contaminated with building salts and moisture and made it necessary to use a renovation plaster system. Normal lime cement plasters or, for example, relatively diffusion-tight insulation boards prevent the masonry from drying out further, as the moisture diffusion is blocked. With the barrier effect of such products, there is a risk that the damaging moisture and salt load will be carried to higher façade areas or that it can strain the interior walls. Renovation plaster system In the present application example, the renovation plaster system consisted of a barrier plaster in the area of the exposed basement outer walls in combination with a rigid, mineral sealing slurry according to DIN 18195 for additional sealing against moisture from the ground. This vertical barrier system was brought out of the ground about 15 centimeters to provide additional protection against splashing or rainwater. The terrain connection of the finished plastered areas is particularly important for a permanent and long-lasting renovation measure. To protect the basement wall plaster, this was solved later with a gravel drainage strip during the renovation. Above this area, the renovation plaster system with a renovation pre-injection mortar was used, whereby cleared joints with a depth of more than 20 millimeters were previously grouted with a renovation joint mortar. To ensure greater security against the proven high sulfate content in the masonry,Both products were formulated on the basis of HS cement - this is a hydraulic binder with increased resistance to external sulfate attack. The actual renovation plaster system consisted of a renovation compensation plaster, which was applied 20 millimeters thick, and the renovation plaster itself, which was applied in the same thickness. Due to its physical nature, the renovation plaster is able to store building-damaging salts in the water-repellent pore structure and remove moisture to the ambient air due to the very low µ-value (water vapor diffusion coefficient). Finally, the renovation plaster can be provided with a water-repellent, diffusion-open top plaster or with an equally designed facade coating. Thermal insulation composite system In the higher area of the facade, a special thermal insulation composite system was used. Due to the still relatively high moisture load, the use of diffusible insulation materials was discussed in advance. Ultimately, the decision was made to use an EPS-based insulation system, albeit with perforated insulation panels that have a 3-fold better moisture flow diffusion than conventional EPS panels. Mineral wool insulation boards have an even lower µ-value, but involve the risk of losing both insulation and load-bearing capacity with constant moisture penetration. Due to the poor load-bearing capacity of the old plaster, the thermal insulation composite system had to be designed as a so-called glued and dowelled system in accordance with construction regulations. Conventional dowels penetrate the insulation board and can create additional thermal bridges. In the case of old substrates that are contaminated with moisture and salt, water or saline solution can be led along the dowel shaft into the reinforcement layer or into the finishing plaster and cause further damage here. Therefore, another innovation in insulation technology was used - the so-called adhesive anchor. The adhesive anchor is a special patented insulation fastener that sits below the insulation board and is anchored in the load-bearing masonry. Both the head (plate) of the adhesive anchor and the back of the plate are provided with mineral adhesive mortar (edge bead point method) and thus glued to the substrate. The wind suction forces (calculation according to DIN 1055-4) are transmitted through the shaft of the fastening elements into the stable subsurface. The adhesive anchor is part of a building inspectorate approved ETICS system. The advantages of this system are that the dowel sits completely underneath the plate, does not penetrate the insulation material and therefore does not create a thermal bridge and also no transport route for moisture or salt solution. Coordinated plastering mortar is used as reinforcement plaster and also for the top plaster layer, which ensures the diffusion ability of the entire insulation system. Careful analysis, detailed redevelopment planning and professional implementation made a comfortable and energetically sensible living possible in the monument. The adhesive anchor is part of a building inspectorate approved ETICS system. The advantages of this system are that the dowel sits completely underneath the plate, does not penetrate the insulation material and therefore does not create a thermal bridge and also no transport route for moisture or salt solution. Coordinated plastering mortar is used as reinforcement plaster and also for the top plaster layer, which ensures the diffusion ability of the entire insulation system. Careful analysis, detailed redevelopment planning and professional implementation made a comfortable and energetically sensible living possible in the monument. The adhesive anchor is part of a building inspectorate approved ETICS system. The advantages of this system are that the dowel sits completely underneath the plate, does not penetrate the insulation material and therefore does not create a thermal bridge and also no transport route for moisture or salt solution. Coordinated plastering mortar is used as reinforcement plaster and also for the top plaster layer, which ensures the diffusion ability of the entire insulation system. Careful analysis, detailed redevelopment planning and professional implementation made a comfortable and energetically sensible living possible in the monument.does not penetrate the insulation material and thus does not create a thermal bridge or a transport route for moisture or saline. Coordinated plastering mortar is used as reinforcement plaster and also for the top plaster layer, which ensures the diffusion ability of the entire insulation system. Careful analysis, detailed redevelopment planning and professional implementation made a comfortable and energetically sensible living possible in the monument.does not penetrate the insulation material and thus does not create a thermal bridge or a transport route for moisture or saline. Coordinated plastering mortar is used as reinforcement plaster and also for the top plaster layer, which ensures the diffusion ability of the entire insulation system. Careful analysis, detailed redevelopment planning and professional implementation made a comfortable and energetically sensible living possible in the monument.
Practice plus
The Baumit open insulation system was used for the facade renovation of the historic residential building in Weil der Stadt. At the heart of the ETICS are perforated EPS plates, which enable a higher moisture flow diffusion. Baumit adhesive anchors were used for fastening. The advantages of the adhesive anchor are that the dowel sits completely underneath the plate, does not penetrate the insulation material and therefore does not create a thermal bridge or a transport route for moisture or salt solution. Further information on the products: Baumit Tel.: (08324) 921-0 / Fax: -470 www.baumit.de