Thermal insulation makes it possible – visually attractive
When half-timbered houses are thermally insulated, usually the visual appearance changes and the masonry filling is then lost. Not so in Schmallenberg, where the Landgasthof Vollmer-König has even gained in appeal with the Capatect system from the company Caparol.
Half-timbered houses are popular photographic subjects, particularly when they have been elaborately restored true to detail. They represent tradition and embody a constructional period in which prefabricated components were not conceivable. Framework is especially typical for thickly wooded regions. This also applies to the Sauerland which at the same time represents a region close to nature with a rich history. For example, many Federal Gold Villages – winners of the national competition "Our village should be more beautiful" – are located in this heavily forested uplands region in the south-east of North Rhine-Westphalia. Schmallenberg is a small town in the Sauerland with a 1,000-year history and now has a population of about 27,000.
An impressive sight in this town is offered by the Landgasthof Vollmer-König, which, with its hotel rooms and four holiday apartments, a swimming pool and a sauna, is a magnet attracting many overnight guests. However, its framework is not really one in the true sense. The wooden beams were superimposed and had in the meantime almost rotted through. Since the facade had to be renovated anyway, the proprietor, Jörg Vollmer-König, decided to save on heating costs by having a climate-friendly thermal insulation composite system fitted.
First, the Schmallenberg Master Painter Alfons Mette had the rotten wooden frame removed from the facade, so that the render base was prepared for applying the following layers. The subsequent procedure was then defined together with Kurt Walter Pöll, who as Field Sales employee represented Caparol in the Sauerland. Work started with gluing and plugging Dalmatiner-Fassadendämmplatten 160 insulation boards. They are16 cm thick and are used for high insulating performance. The black/white spotted rigid polystyrene foam boards have a 13 percent improved thermal insulation capability which reduces the insulation thickness required. The Capatect insulation board is well-equipped against thermal influences. It hardly heats up even under direct solar radiation, so that any possible shrinkage is eliminated from the start and the low flammability boards retain their original shape. This also relieves the joints to the substrate. On the country hotel additional hold is provided by the Capatect-Universaldübel 052 plugs – the screw plugs with building supervisory approval for the mounting of Capatect facade insulation boards.
The adhesive used was Capatect-Klebe- und Armierungsmasse 186 M (adhesive and reinforcing compound). It is a mineral factory dry mortar suitable for use with machines which is intended for bonding insulation materials and for providing mesh-reinforced filler layers. The compound is also non-combustible and of low flammability in combination with other products. It is weather-resistant, water-repelling, highly permeable to water vapour and environmentally friendly. Application workers also like the long pot life and the very good non-sag properties, whereby the enhancement additives are responsible for the hydrophobizing.
The following layer consisted of the Capatect-Gewebe 650 mesh which glued on over the whole area. This special non-slip reinforcing mesh of glass fibre is also embedded in the Capatect adhesive and reinforcing compound, it is highly stretch resistant and free from plasticizers. The following render layer was produced from factory dry mortar, Capatect-ArmaReno 700. It has a fire classification of "non-flammable" or "low flammability", it is weather-resistant, water-repellent, but highly permeable to water vapour, has a long pot life and excellent non-sag properties. ArmaReno is a high quality all-round mortar which is suitable for mounting insulation boards and as a reinforcing compound in the Capatect system.
As before, but better.
In Schmallenberg the complete surface was felt-wiped with a sponge board. For equalisation it was given a coating of ThermoSan, the Caparol facade paint based on silicone resin which reliably protects against algae and fungal attack and is suitable especially for ETICS as well as mineral and synthetic resin-bound surface renders. With its nano-quartz system ThermoSan offers long-lasting moisture protection and high water vapour permeability. Fine cracks in the render are also filled. Now Alfons Mette's three employees need only to transfer the previously photographed frame to the facade and paint it in black in Capalac.
In total this project took them three weeks to complete. The difference is however hardly visible, because the old appearance of the house is very similar to the new one, even with thermal insulation. The framework has been completely "retained" and will adorn the townscape also in the future. Also, the proprietor can delight in improved heating cost figures.
Photographs: Caparol Farben Lacke Bautenschutz / Martin Duckek