Finstral glazing: the way to the low-energy standard
“Climate-fit” with new glazing
In the 1980s the client built a representative villa, lacking nothing in architectural comfort and luxury, for himself and his family in the Italian city of Brixen. Inadequate thermal insulation and an out-of-date energy concept was however increasingly eroding the charm of the magnificent 30-year old structure: a refurbishment was due.
Time passes, family structures change, and building standards that once represented the ultimate also begin to show signs of age. Climate change and rising energy prices too have transformed the ecologically and economically sensitive exploitation of resources into a serious issue. In order to save energy costs, increase living comfort and significantly augment the value of his property, the house-owner decided on a modest conversion with modernisation of the heating aspects.
The Italian climate house (CasaClima) standard is a quality seal for residential buildings – similar to the German efficiency house standard - which has its roots in South Tyrol and has in the meantime increasingly gained in importance throughout the country. For the horseshoe-shaped complex, with its large gross heated volume of 2,000 m³, to be transformed de facto into a low-energy building however required a number of perfectly harmonised measures. Energy consultant Kurt Bacher from the Brixen architecture firm of Dr. Arch. Ralf Dejaco therefore took on the planning and co-ordination work, while the works were implemented by the South Tyrolean building firm of Krapf.
Few changes were to be made to the layout of the villa, which extends over three floors on a sloping 2,500 m² sloping plot with a pool in the north of Brixen. While the generous floor space was originally inhabited by just one family, it was decided to divide the house in two separate housing units in order to enable the daughter of the head of the household to live there with her family in future too. An apartment for guests was also to be added in the basement, necessitating the removal of a stairway and expansion into new areas. Spaces that had previously served as terraces were converted for use as rooms in the family dwelling on the upper floor.
Reducing energy consumption
In order to achieve the required Climate House standard for the existing building, the building shell first had to be thermally optimised with a thermal insulation composite system. The old oil-fired heating system was removed and the building connected to the district heating network, with heat now distributed throughout the house by means of comfortable under-floor heating. The house was also fitted with a ventilation system featuring heat recovery, allowing some 40% of the consumed energy to be recovered from the room air and transferred to the fresh air. A major element of this harmonised energy concept was however the replacement of all glazed areas in the house: the installation of FIN-Project and Finstral’s Vista window wall system as the new window and door system ensures outstanding thermal insulation values, maximising solar heat input in winter while at the same time providing effective heat protection in summer.
Slender window profiles, high light incidence
All windows and window doors in the house were replaced with elements from the innovative Finstral FIN-Project window and door system, which sets new standards in aluminium window construction. The symmetrical appearance of the combination of fixed glazing and sash areas contributes to the house’s harmonious general impression. Scarcely visible from the outside, the window sash es with their elegant, slender profile look mean a high glazed proportion and thus maximum light incidence in the entire building. While triple glazing was used on the colder northern side, double-glazed window and door elements were sufficient for the sunnier south side, thus making best use of the incident sunlight’s passive energy as solar heat input in winter.
The five available sash variant s of the FIN-Project system offered a solution for every structural and design requirement of the existing structure. The villa’s owner and the planner opted for FIN-Project Nova-line, a modern, concealed sash variant with a slender appearance and a satin-finished, matt steel-coloured surface. Despite their slender profiles, the room-high elements are particularly resistant to distortion thanks to the all-round bonding of the sash frame work with the glass, thus guaranteeing excellent stability and a particularly long life.
Outstanding insulation values even for very large glazed areas
This innovative product manages to offer an aesthetically pleasing design combined with high energy efficiency, because the new system structure of FIN-Project elements, consisting of a multi-chambered PVC profile with a central seal , firmly bonded inside and outside with aluminium profiles, itself offers an extremely slender profile and at the same time excellent thermal insulation (up to Uw = 0.78 W/m²K) as well as high air tightness and protection against driving rain. Thermally insulated transitions, insulated windowsill junctions and the standardised use of thermally optimised glass spacer s prevent heat bridges. The FIN-Project system was combined with the Finstral Vista window wall for the new stairway area: the large sliding openings and slender mullion-transom construction make this the ideal aesthetic and energy solution for the glazing of large surfaces. External aluminium venetian blind s for the living areas and textile roller blind s to protect against the sun in the bedrooms ensure thermal protection in summer and make it easy to control the large incidence of light on the sunny side.
Text reference: pro publica