wooden passive house CV1Edit profile
The first wooden passive house CV 1 Kupinecki Kraljevec, Zagreb, Croatia Family house “CV1` is the first wood-made passive house designed in 2003 that is realized in 2008. The special characteristic of the project is that it uses the material of an old traditional wooden house as the part of the new facade. In accordance with the natural values of the site and the requirements of quality living and protection of cultural heritage, the CV1 house project, by the size of the building and by its materials, is based on maximum adjustment to the existing plot and the broader environment, with the requirement of high energy-efficiency and sustainability. The house is rectangular with protruding northern volume of the entrance, staircase, studio and wardrobe on the upper floor. It is only in part of this volume that northern facade rises above the eave as a protective wall for solar converters and a kind of mask hiding them from public view. Southern facade is open to the maximum, and northern facade is almost entirely closed, except for the openings at staircase landings. Project brief envisages a ground floor and the 1st floor with a gallery over part of the living room. The roof is single-pitched falling to the North. To prevent overheating, a large eave overhang is designed as a protection from sunshine in the summer, with the appropriate geometry of the facade cross-section enabling a full exposure to sunshine in the winter throughout the depth of primary spaces. The roof is to accommodate solar thermal and photovoltaic converters. Part of the slanting roof above the upper floor (and ground floor) level is to carry a green cover. The envisaged values of construction physics meet the requirements of a passive house as the basic precondition. Installation active system includes a heat pump (air heat exchanger), a ventilation system, solar thermal and photovoltaic converters. This project is chosen as a referent example in the recent ISOVER publication Darauf baut die Zukunft: das ISOVER Multi-Komfort-Haus` in the topical part “Die Möglichkeiten` (“Possibilities`). External elements of the building, excluding the glazed surfaces, are insulated so that the heat transfer coefficient U does not exceed 0.15 W/(m2K). The building has to be maximum airtight that should be proved by measurements (blower door) so the air exchange difference at the test pressure of 50 Pa must not exceed 0.6 h-1. Glazed transparent surfaces have heat transfer coefficient (Uv) below 0.8 W/(m2K), whereas the degree of light transparency should not fall below 50 percent (g> 50 percent), to enable thermal gains in the winter period. Such characteristics are achieved by means of triple glazing filled with argon. Thermal insulation window frames are installed without heat bridges to achieve the required overall heat transfer coefficient for a window (UF) of less than 0.8 W/(m2K). Highly efficient heat retrieval in the ventilation system with the utilisation rate of more than 75 percent is achieved with a low consumption of energy (<0,45 W/m3). Passive house in Croatia becomes a topic of great interest for architects, other experts, investors and builders. The use of renewable energy sources enabled the accomplishment by far the biggest energy savings in the construction industry, ensuring optimal conditions for healthy living without harmful gas emissions. Even the accomplished energy efficiency and already corroborated favourable investment effectiveness lead to new forms of financing incentives to such construction, energy standard and relevant changes of long-term energy strategies in the EU member states that is still not offered and accepted as a model in Croatia.