The planned private house was designed after the fashion of the two-storey dwelling houses characteristic of the Bulgarian rustic architecture. Like in the traditional buildings, the upper storey overhanging the ground floor accommodates the bedrooms and bathrooms while the living room provided with direct access to the garden and the kitchen and dining room occupy the ground floor. Also the building’s structure and exterior facing reflect the traditions, using robust bricks topped by light timber structure on the floor.
Beyond the respect paid to traditions, the appropriate thermal engineering design of the passive house’s structure, the maximum possible use of recycled materials and ensuring the smallest possible “carbon-footprint” governed the selection of the building materials. The ground floor’s load-bearing and façade walls are built using salvaged bricks, heat bridge interrupting recycled foam glass slabs are inserted below the bearing walls and also the gravel bed usually spread below the ground floor structure is replaced by foam glass blankets. Also the primary heat insulating material, i.e. the cellulose blankets are made of recycled material.
I tried to arrange the floor plan to achieve the best space-to-exterior-surface ratio by employing elliptic shape. The optimum orientation of the façade doors and windows maximizes the building’s heat retaining capacity in winter and proper shielding solar screens minimize the heat load in summer.
The recuperative ventilation system is an essential component in passive houses and is the core element of building engineering in this case, as well. Plasterboard panels are suspended on both storeys below the load bearing ceiling as to conceal the building engineering ducts, to simplify installation and to ensure ease of subsequent repairs or replacements. At the same time, the gypsum plasterboard panels constitute integral parts of the heating system: low-temperature water pipes integrated in the panels enhance efficiency of heating in winter. A broad variety of engineering solutions can be incorporated also in case of a passive house. The most appropriate combination of such solutions can primarily be selected on the basis of rational economic calculations.