Construction of passive housesConstruction of building with use of passive house technology on a turnkey basis. Our Company will completely undertake construction of passive house from preparation of schematic design to completion of construction works. Therefore, clients discuss all their ideas with our designer in details, and then they get the house ready for accommodation.
Construction of passive house may be executed everywhere. However, strict compliance with some requirements has a great role.
Thermal envelope of house
Standard coefficients of heat transmission
Passive houses differ from conventional houses by many parameters. The crucial parameter of the passive house is its massive heat insulation and air tightness for reduction of heat losses. Maximum heat insulated fencing structures in the best combination with other components allow achieving pleasant indoor microclimate and required energy saving. High standards are set for construction elements. For instance, it is recommended to select heat transmission resistance coefficient of elements more than Rо=6,67(m2оС)/W.
Enclosed envelope is required for the following reasons:
- prevention of condensation in the structure
- prevention of draughts
- prevention of cold floor on the ground floor
- prevention of harmful substances in inside air
- provision of sound insulation of structural elements
- provision of operation and effectiveness of ventilation units
- provision of heat insulation properties of external fencing structures
- reduction of ventilation heat losses
Air tightness of heat insulated structures has a significant role from many perspectives. It reduces infiltration (through passage of air from outside to inside) of cold air, which leads to draughts and increases heat consumption. It protects the structure from exfiltration (through passage of air from inside to outside) of warm humid air, which may lead to moisture (condensation of moisture in the structure) and harm the construction structure. Proper design, evaporation and verification testing of constructed envelope are required for the passive house, as well as for each other facility.
In course of construction, air tightness testing of surrounding structures is performed for verification of quality of heat insulation works (Blower-Door method). Total volumetric and mass air flow for the entire building is measured by injecting and pumping air into the room with a given pressure difference inside and outside. Air exchange is considered optimal when all air in the room at a pressure of 50 Pa is replaced within one hour, and leakage through uncontrolled cracks in the building envelope does not exceed 60% of the total room volume (coefficient 0.6), that is: n 50 = 0.6 Vtot/ hour.
Temperature stratification is closely related to living comfort. Windows have an important role in this factor. Cold temperature at the window surface acts as a draft (mechanism) for air movement in the room. Warm air is cooled at cold glass and stream down to spread at few meters on the floor.
Double-compartment windows with heat insulated glass and heat transmission coefficient less than 0.8 W/(m2 °C), including frame and window crosspiece provide very low heat losses. Inter-glass space is filled with inert gas (argon, xenon), and glasses are covered by special invisible metal spraying, all these means provide high heat transmission coefficient. At the present time multiple-film insulating glass units with Ro = 3.6 (m2 oC) / W have been produced.
External surface of passive house windows is significantly colder, than surface of windows with standard glass, due to high thermal protection. As a result external surface of window glass may be wept in relevant temperatures. This effect confirms high quality and disappears over the time. It depends on installation (assembly) of window.
In case of optimal installation, we achieve value – Ψ installation – approximately 0W/(m – oC). It is important that the window is located in the heat-insulating layer and that the outer window frame is additionally heat insulated. Thickness of 6 cm is applied for additional heat insulation (in the figure: along the horizontal line).
Conventional method of installation has adverse consequences. Value Ψ installation equaling 0,15 W/(m-oC) increases Uw installation up to 1,2 W/(m-oC). It shall be pointed out that a similar value is obtained in optimal installation of significantly cheaper conventional window. Isotherms are collected in a weak spot, forming heat efflux during the whole service life of the window. In this case there is “a gap (in heat insulation) with heat emission” (dark red lines of heat flow).
Heat pumps are divided into geothermal (ground) and air. As it is stating from its titles, geothermal pumps use heat of ground as the source, and air pumps use air. Air heat pumps are less expensive (including installation costs), however, they operate under temperature not less than -15oC. Therefore, use of these pumps is limited in our conditions. Geothermal heat pumps have no limitations for ambient temperature.
Productivity of up-to-date geothermal heat pumps (COP - coefficient of performance) is up to 5. It means that heat pump produces 5kW of heating energy for 1kW of consumed electric energy. This indicator is lower for air heat pumps – approximately 3.
Package of services includes:
- design of “smart house” systems;
- establishment of integrated complex of all engineering systems (security, multimedia, telecommunications, lighting, curtains drives, climate control) and its aligned operation;
- arrangement of centralized control of equipment from mobile devices or wall panels;
- programming of operating patterns of all systems;
- maintenance of systems.
ABILITIES OF “SMART HOUSE”
Smart House technology is able to implement almost anything that you can imagine. Artificial intellect system provides opportunity to control any electric appliances. House automatics undertakes control of all systems: from essential services to entertainment, from security to climate control.
Our Company deals with installation of the following system:
- control of light types;
- control of lighting as per outdoor light;
- control of light as per lighting level and presence of people in the room;
- control of curtains;
- control from touch screen panel or mobile device;
- button “Turn off”.
- home theater;
- media network;
- broadcast and satellite TV;
- wire and wireless
- security and fire alarm;
- indoor and outdoor video surveillance;
- control and access control;
- passive security (protection from leaks of gas and water, control of CO level).
- climate control system;
- control of air humidity and ionization;
- establishment of integrated climate control system.