Glass carries walls – Innovative glazing solution allows new building forms
Meters wide and high glass sheets make a single family home in Haselbach into a perfect viewing station. The trick: thanks to a novel method of fixed glazing system, additional stiffening could be avoided.
Elevated – for the best of views
The desire of the home builder – a house on a slope with about 150 m² living space, a clear a simple concept using as much solid wood as structure and a lot of glass, so that the natural landscape can be appreciated without disturbance – was achieved so perfectly by the architect in his first conceptual design that he got the contract. His concept was based on three boxes, which poked out like fingers into the landscape. Each box integrates a different function. In the first one there is cooking, eating and living. The second serves as the sleeping area and the third as office. Along the back, the three boxes are joined by a connecting tract. In this tract there are the functional areas of the house such as entrance hall, storage, bath and WC. This makes each of the three wings independent but still primary parts of the single family house..
Walls of glass – a climate-compatible building element
On the slope, the three boxes look for ground contact. Towards the valley they stand on stilts and are cantilevered. Three doors – the house entrance, the bedroom door and a side exit – are connected to the outside. The rest of the house is connected to nature by huge glazed areas. All glass units are fixed glazing in the system CLIMAplusWOOD [>]. „That is unusual, but thanks to space ventilation very comfortable“ says the architect Karl Heinz Schwarz. The building captivates both inside and out with its interplay between wood and glass and brings assurance through its energetic optimum passive house concept.
Intelligent building stiffening with CLIMAplusWOOD
The visual crown of the building is the expansive glazed area of the facade construction. There are 5m wide and 3m high, lotus-like glass elements with „easy-to-clean“ BIOCLEAN [>] coating, to which 1.40 m wide by 3 m high corner elements – from which there is nothing to be seen of their connection “from outside you can only see wood from the adjacent façade, then there is already glass” comes from the architect in a happy voice, “there are not even any diagonal stiffeners”. That was impossible to achieve not so long ago. Without pressure plates no glazing. Without tension cables or other diagonal stiffeners no large glass areas. This was the recent rule for large areas of glazing – until now.
A recent development from the glass specialist ECKELT and the connection manufacturer KNAPP, allowed the hybrid application to be achieved in Haselbach. The wood-glass laminate system CLIMAplusWOOD is based on the concept that the installed glass is structurally supporting as one of the outer-lying sheets takes the load function. In this sense it is possible to avoid stiffeners. After installation, the system is immediately structural, wind and weather-proof. „Installation itself is very easy and went very well“, remembers the architect. Under the name Fasco, the GFK plastic profiles are factory bonded to glass under industrial conditions, so that the finished CLIMAplusWOOD glass elements arrive on the site and just need fixing into the window openings. Construction time for single family house is shortened significantly.
As easy as A-B-C
The short time period could only be achieved thanks to the wood construction method, assures Schwarz „The wood construction is much more accurate than concrete and allows good pre-fabrication, and allowed us to build much quicker” Parallel thereto, the glass system from ECKELT used in Haselbach also made installation quicker. „It was already November when we were to begin glazing“, commented Schwarz. Because the weather was so bad, „we were unable to achieve the weather seal straight away, we had to wait a few days“, he informed further. „That was not a problem, because the facade was already sealed.“ The architect had already made a decision about connection method from a choice of three from the manufacturer Knapp. The choice allows the glass units to be removed easily without opening the façade. „It is enough just to cut the silicone joint and the glass can then be changed“ informs Schwarz.
The project in Haselbach is one of the first which uses this kind of glazing. „I would use it again without hesitation“, assured Schwarz. „One saves costs for wind bracing, it is optically more beautiful, and the installation time is acceptably short.“ It must be expressed that installation can only be carried out by experienced and rained personnel – and the system must be incorporated as early as possible in the structural design so that the wind bracing can be omitted..
Photos: Knapp Verbinder