Historic food supply office becomes modern residential building Renovated in line with historic preservation guidelines using flooring solutions from Uzin and Pallmann

“Preserving historic buildings and combining them with attractive modern living space” is how builder Christoph Baumgärtner explains the motivation behind the renovation concept. The 26-meter-long and 11-meter-wide building, which has been expanded in the course of several conversions, has three full floors and two attic floors with eleven residential and commercial units, which are accessed via the two long sides. In cooperation with the historic preservation office, the building was renovated to improve its energy efficiency and structural integrity. Balconies were added to one long side.

While the wall surfaces throughout the building were very heterogeneous, a comprehensive parquet floor with a herringbone pattern as well as historic floorboards and floor planks stood out. Only partially was the solid oak parquet covered by PVC or similar newer floor coverings. On the first and second floors, however, there was significant deformation of the floor in the center of the building. “We had to level out the sunken floor with a slope of up to 20 centimeters,” describes the client the initial situation.

After intensive consultation with the flooring experts at Uzin and Pallmann, the UZIN Turbolight System CA emerged as the optimal solution. It flexibly compensates for unevenness in mixed substrates, imperfections, transitions, and slopes with layer thicknesses of 20 to 300 mm. It adds hardly any weight to the ceiling – a considerable advantage in wooden beam constructions in historic old buildings. “The system combines lightweight construction, high load-bearing capacity, and flexibility,” explains Jürgen Wiedemann, technical consultant at Uzin. For the restoration of the oak parquet, colleague Klaus Huttenlauch from Pallmann recommended the large-area use of the Spider sanding machine, which is gentle on the structure. After sanding, vacuuming, and watering, a natural, solvent-free 1K parquet oil made from regional cold-pressed hemp oil and natural waxes should be used for maintenance. “MAGIC OIL 1K CHANGE emphasizes the structure of the old floor instead of covering it up”, technical consultant Klaus Huttenlauch explains the advantages of this surface treatment.

Due to the static requirements of the listed historic building, care was taken to use the lightest possible construction methods for all work. “Heavy materials or solid construction methods would have overloaded the existing supporting structure,” explains Jürgen Wiedemann, technical consultant at Uzin. Therefore, the use of lightweight building materials and construction methods was essential to ensure the stability of the building. “Renovation with the UZIN Turbolight® system was the obvious choice,” says Wiedemann. “The flooring system is particularly suitable for renovations where flexible installation height and the lowest possible weight per unit area are crucial.” It combines several advantages: high compressive strength despite its lightweight construction, low dead weight, rapid construction progress, and high flexibility, especially on uneven substrates. In addition, it is non-flammable and highly fire-resistant in accordance with F60.

“The floor structure in historic buildings always has to be planned on a very individual basis, especially when there are static challenges,” says Wiedemann. “Due to the different mixed substrates and leveling thicknesses, we applied the UZIN Turbolight system partly with foil on a separating layer and partly in a bonded structure.” In some places, UZIN PE 280 super fast primer was also used to prime mixed substrates. To compensate for the slope, the first layer of UZIN SC 904 lightweight mortar was applied in layer thicknesses of 3 to 25 cm. After just 24 hours, work can continue on the light leveling layer and the UZIN RR 201 renovation fleece can be laid overlapping across the entire surface. As a base layer, the self-leveling thick layer levelling compound UZIN NC 567 connects the components of the system to form a level, stable subfloor. FusionTec thick layer levelling compound can be used very flexibly to create virtually tension-free bonded substrates, floating or on a separating layers. FusionTec thick layer levelling compounds also dry quickly and are label-free. They are ready for covering after just five days.

“The challenges with this property were preserving the historical substance and complying with monument protection regulations,” summarizes Pallmann technical consultant Klaus Huttenlauch. “However, we quickly found suitable solutions for the historical parquet floors and the staircase,” adds Huttenlauch. Sanding with the Spider parquet sanding machine is particularly suitable because it works precisely and gently on the material, ensuring an even surface without loss of substance. The compact Gecko Flex 2.0 angle grinder is ideal for corners and edges. MAGIC OIL 1K CHANGE enhances the color and structure of the wood and offers lasting protection.

“Refurbishing historic oak parquet flooring requires a delicate touch, and the advice provided by parquet specialist Pallmann was very helpful,” recalls Christoph Baumgärtner. “We chose a combination of liquid hemp oils and hard wax as the surface finish, which is ideal for historic floors,” explains technical consultant Huttenlauch. The MAGIC OIL 1K CHANGE oil-wax combination creates an open-pored, breathable, and diffusion-capable surface. The wax content ensures that it retains its natural appearance and remains water- and dirt-rejecting. The client also attached great importance to using products that were as natural as possible. The use of renewable raw materials such as hemp from regional, organic agriculture also reduces CO2 emissions. Important for indoor use: the finish must be solvent-free and at the same time resistant to household chemicals and easy for users to maintain.

“Preserving the classicist building not only conserves resources, it is also extremely important for the cityscape,” Christoph Baumgärtner is convinced. The renovation is an example of how historic buildings can be upgraded with modern flooring systems. “Thanks to the coordinated floor structure, we found a professional solution for renovating the floor in all areas of the building with Uzin Utz,” confirms the client. Now the historically renovated residential building in the city center with historic parquet flooring and staircase can be handed over to new users.