New National Gallery Berlin: Floor area renovated with special construction in a uniform appearance

In addition, only products that passed the Oddy-test for suitability for use in museums and did not cause any harmful emissions were required. UZIN was the only supplier to offer a suitable solution and recommended a state-of-the-art floor construction – professionally executed by IB Fußbodentechnik Berman GmbH from Berlin.
The heated screed construction in the basement consisted of approximately 7 x 7 m² fields with individually controllable heating circuits. The challenge was to transfer the expansion joints from the subfloor construction to the top floor in accordance with DIN 18365. However, the monument preservation authority clearly rejected the use of joints, as it wanted a homogeneous carpet surface. The solution was a construction recommendation from UZIN, which allowed the textile covering to be laid continuously over the expansion joints.

To do this, after sanding and priming, the joint areas were milled approximately 30 cm to the left and right of the joint, and expansion strips were cut down to a wedge shape of approximately 20–25 mm in a special way. The team then inserted crack bridges into the joints, which were bonded with a 2-component PUR adhesive. Finally, the joints were completely filled with the adhesive and smoothed again. The glass fabric absorbs the tensile forces in conjunction with the adhesive. A total of approximately 700 meters of joints were closed in this way.
After the drying time, the entire surface was sanded again and primed with a quick primer. To separate the carpet from the subfloor, an insulating underlay was then laid over the entire surface with a shear-resistant adhesive. It decouples and absorbs movements, and also ensures better walking comfort, dimensional stability, and impact sound insulation.

Since the carpet installation required a very level substrate, Uzin recommended the self-smoothing rapid gypsum leveling compound UZIN NC 112 Turbo, which has excellent flow properties and forms smooth and homogeneous surfaces. Around 50 tons were pumped up to 150 m to the construction site and applied in a layer thickness of approx. 5–10 mm. After about six hours, the floor was already ready for covering. Due to the size of the floor area and the high traffic, the low tension and very high compressive strength (C40) of the quick-setting filler used were particularly important. It is highly resilient, quick to cover and suitable for all floor coverings. It also has very low emissions according to EMICODE EC1Plus, has EPD and Blue Angel certification, and passed the specified Oddy-test, which checks the compatibility of materials for museum rooms. The result in the exhibition space impressed both the contractors and the client: a level substrate and a continuous floor surface allow full concentration on architecture and art.