When refurbishing the 360 m² of living area, the floor was very much a focus. The building owners wanted underfloor heating installed, and nostalgic XXL floorboards in varying lengths from 3-6 m as the floor covering throughout the ground floor. The three-layer floorboards, 20-35 cm wide and 18 mm thick, were to be installed solvent-free and shear-resistant in château plank style. The floorboard specialist Fendt took on the task of producing and colouring in oak patina without chemical additives.
Flooring structure with high requirements
The heavy wood flooring and the drummed natural sandstone in the kitchen and hall first required an especially load-bearing and even substrate. Undulations in the rough ceiling of up to 5 cm had to be smoothed for this, and the subfloor had to be adjusted to the different thicknesses of the natural stone and solid wood flooring. “The challenge in this measure of modernisation lay predominantly in the extremely low and varied structure heights for the comprehensive installation of the thin bed heating,” explains UZIN screed expert Uwe Kunzelmann. Due to the existing built-in components - stairs and doors inside and leading to the outside - only a very flexible system could be used for the floor construction that would delicately smooth out the different heights and also have high load-bearing capacity for different thicknesses. A floor that was sensitive to moisture was also necessary in the bathroom and WC.
Uzin Turbolight system as a problem solver for low flooring structure
The total structure height available in the Tegernsee Villa was only 50 to 100 mm at most. “The UZIN Turbolight system is unique here, because it can be drawn out to be extremely thin,” explains Horst Stefan, screed specialist at Laskowski. “Thus we were able to manufacture the load-bearing floors true to size, and work precisely in the millimetre range, and the bundled filling worked perfectly at the height.” The patented UZIN Turbolight system consists of the load-bearing light smoothing mortar UZIN NC 194 Turbo as a foundation. This is applied with common screed technique - pumped, manually blended with a stirring machine or free-fall mixer - in the desired thickness of 30 cm, and then pulled flat. It transfers occurrent loads evenly to the substrate, even when thicknesses vary. A reinforcement fleece made of long glass fibres with high tensile strength, which is laid on the underfloor heating, combines with the thin screed UZIN NC 195 following on top of it as a third component. The cement levelling compound can be installed as a fluid smoothing layer of 3-40 mm. The installation materials coordinated with each other thus form a high-tenacity fibrous composite material that allows for fast, flexible, and large-size levelling of 5-300 mm. The time until readiness for covering was no more than 72 hours in the current project. In addition, the system is heat insulating, acoustic grade, waterproof, and low-tension.
Advantages of the Uzin Turbolight system for installing wood flooring
“The high load-bearing capacity is an absolute necessity when it comes to shear-resistant installation of long solid wood floorboards. A precast concrete wasn’t an option here, only a poured screed can handle the weight of the floor covering and still serve as a balancing layer to prevent the large-size boards from sliding,” explains Hubert Egle from Fendt Holzgestaltung. “For this purpose, the building owners mostly wanted a jointless installation of their floors.” The 18 mm-thick, three-layer floorboards are made up of a 5 mm oak each as a wear layer and balancing layer, and an 8 mm-thick substrate layer. When choosing the wood, the tree is used in its natural length and width with the branchiness left out. This enhances the authenticity of the floor, just like the classic surface design with clean, natural treatment.
“Precise work, flexible materials, experience, and sure instincts ensured a perfect result,” says Markus Krieg, project consultant of wood flooring for UZIN. “For this type of low structure heights combined with underfloor heating, however, the technical competence of the contractors and the good teamwork between the crafts in the team with architect and UZIN consultants was crucial.” Working with established system materials that were coordinated with each other, from the substrate supporting the upper edge to the floor covering, meant the floor layers could also maintain maximum security in case of a warranty claim.