A height of 20 millimeters for underfloor heating and screed is not much. But the installation is feasible with the cooperation system of PCI and Roth. The solution was convincing in the core renovation of a farm in Monschau. Because it is simple, fast and practical.

The farm from 1938 is located on the outskirts of the half-timbered town of Monschau which is idyllically situated between mountain slopes in the Rureifel. The individual property has always been family-owned. Lutz Müller planned the complete renovation of the building to preserve his grandparents' house for future generations and to meet the demands of contemporary living. The focus was on sustainability. The renovation was carried out ecologically where possible. Some walls have been knocked out to make large, friendly living spaces out of the once small rooms. Underfloor heating should ensure a pleasant temperature in the cold-floor rooms in the living-dining room with open kitchen and the two bathrooms.

Different assembly heights

After dismantling the old surface, inhabited by mice, the low construction height became visible. A steel girder ceiling without any insulation was under the floorboards laid on battens. The construction heights varied, around six centimeters at the lowest points. After the floor construction was built up, only around two centimeters would remain for the installation of the underfloor heating. Lutz Müller, himself a master carpenter in the construction industry, sought advice from PCI consultant Sascha Wilden and carried out the jointly developed planning with the commissioned plumber. After leveling out the unevenness on the raw ceiling, XPS insulation boards were first bonded with the flexible 2-component reactive waterproofing PCI Barraseal Turbo. The mineral waterproofing slurry is used in variable layer thicknesses and is suitable not only for bonding insulation boards but also for waterproofing work. The substrate could be primed with PCI Gisogrund 404 after a short setting time of only around three hours. The solvent-free special adhesive primer can be diluted with water and is easy to apply thanks to the violet control color.

Minimum structure: System for retrofitting in old buildings

The plumber bonded the thin-film underfloor heating to around 60 square meters of the prepared substrate. With the extremely low structure of 17 millimeters, the Roth ClimaComfort® Compact system is ideal for retrofitting old buildings. Processing is easy: The self-adhesive system panels can be cut to fit perfectly without cracking and easily attached to the substrate, the system pipe can be installed reliably thanks to the special shape with undercut. The craftsmen then filled the assembly of system panels and system pipe with PCI Periplan Extra. The fiber-reinforced special filler is suitable for layer thicknesses of 3 to 60 millimeters under textile and elastic floor coverings. Low in dust and self-leveling, even pumpable, the floor leveling compound is very easy to work with. Like the primer used, PCI Periplan Extra is very low in emissions according to GEV-EMICODE EC 1 PLUS.

New underfloor heating in three days

"The new underfloor heating was installed in three days and also has the advantage that no further leveling compound is required for the subsequent laying of the vinyl floor. That accelerates the construction progress," says Lutz Müller and adds: "The ClimaComfort® Compact system together with the PCI products completely convinced me, also for my own business, the construction of turnkey wooden houses. The fewer trades required for a construction phase, the better.”