Following the executed surveys of the real estate we arrived at the decision described in the design.
The volume of the building is compact, with proportion (ratio of surface area and volume) S/V=0, 65, which is less than the volume of a cube with length of the wall of 9 m.
The sunscreen devices along the southern facade are with changing inclination, not admitting sun rays in summer, and to the opposite admitting them in winter.
At the base of the southern facade, at the foundation of the wooden farms there is an inclination which we use to direct the reflected sun irradiation towards the building (in winter months).
Traditional houses in cold climate areas are with roofs inclined towards the unfavorable direction and windows mainly along the southern facade. We thus solved the inclination of the roof to the north.
We also use controlled forced ventilation by cooling/heating of the fresh air via ground air heat exchanger in the soil at a depth of 4 m where the temperature in winter months is between 5ºС – 10ºС, and in summer – between 10ºС -15ºС. The air heated in the house using a recuperator delivers heat to the incoming fresh air, so therefore recovery of the energy from the spent air is in place.
To achieve the high energy efficiency of recycling of spent heat, we use heat exchanger with the so-called counter-current or opposite scheme of movement of both flows – the supplied fresh external air and the spent internal air. Their efficiency reaches 95%, and minimum is considered to be 80% „back recovery” of the energy.
We analyzed the sunlight, shading and the wind rose during all seasons. The prevailing winter winds are mainly south-western and western. The existing building and tree vegetation with the orientation we have chosen are situated to the west and form a natural protection against the winter wind, moreover they do not overshadow the building.
The natural heat in the exterior areas depends on the location of the sun and the properties of the ground surface to give out. Therefore, the heat curve is lags behind against the curve of the height of the sun with about one month, i.e. the hottest day is not June 21 but somewhere around the last days of July, and the coldest day is not December 21st but some of the last days of January. The degree of falling of sun rays in summer (June 21, 12:00 h.) for this geographical latitude is 70º7´, and in the end of July it is about 60º. This way we determined the inclination of the southern facade.
Design: Ivan Ivanov
Structure: Schteryou Komsalov
Installations: Emil Tzanov