I. Definition of passive house
1. Passive House is an internationally recognized energy-saving architectural design process that integrates comfortable living, low energy consumption, and economical efficiency;
2. By taking advantages of its superior performance in thermal insulation and airtightness, it makes the use of every natural heat gain resources accessible (including solar, illumination, human body, and electric appliance radiation) to maintain a room temperature above 20 C° and a high indoor comfort level;
3. The “passive house” can be any type of building;
4. Currently, a total of more than 6000 passive houses have gone into full operation in China, Germany, Austria, and Switzerland.
II. Features of passive house
1. The most distinguishing feature of a passive house is to achieve indoor comfort both during winter and summer without using a traditional active HVAC system;
2. The construction of a passive house focuses mainly on solving heating issues in the winter. The core idea of the design is to minimize the heat loss of the building.
3. The key technologies can be summarized in the following two areas:
① Energy conservation technology employed in building envelopes;
Thermal insulation system
1) Building envelope thermal insulation
2) Roof and floor thermal insulation
3) Thermal bridge treatment
4) Airtightness
Energy-efficient windows
1) Triple-pane Low-E insulating glass
2) Vacuum insulated glass
② Fresh air ventilation technology. A fresh air ventilation system consists of a ventilation system with heat recovery.
III. History of passive house
1. The “Passive House” concept originated in 1996;
2. The earliest “Passive House”was built in 1999 - a wooden structure consists of 90 m2 3-bedroom units.
3. Construction cost is only 7% higher than ordinary houses. But the operating costs are extremely low;
4. By using solar energy, it achieved self-sufficient in heating and electricity;
5. In 2004, the annual consumption of heating, water supply, and electricity costs each household only 114 euros.
6. The world’s largest passive office building - Energon was built in Ulm, Germany in 2002.
IV. The representative work of passive house in China - Hamburg House
1. Hamburg house is the first structure certified as a passive house in China and was exhibited in the Hamburg pavilion of the Urban Best Practices Area at Shanghai World Expo.
2. The “Hamburg House” consumes 50 kilowatts of energy per square meter per year, one-fourth of the average energy consumption of an ordinary office building.
3. The roof-top solar equipment provides 90% of the electrical energy for the building;
4. The energy for heating/cooling the building is produced via a geothermal heat pump;
5. The surface of the brick wall looks just like the ordinary red bricks, but the thermal insulation performance is much better;
6. The 3-pane specially crafted glass window uses wooden frames sealed with special thermally insulating materials to provide excellent heat preservation and airtightness;
7. Heat sources from sunlight, the human body, and radiation of indoor appliances are used to fulfill most of the thermal needs in the house;
8. The central ventilation system can supply heated or cooled dehumidified fresh air to all rooms;
9. The north side of the “Hamburg House” is covered with curtain wall;
10. The specially designed windows on the west and south sides can be switched on and off automatically according to the sunlight.
Hamburg House
In less than 10 years since the “Hamburg House”, passive buildings have emerged in several cities in China including Qinhuangdao, Qingdao, Tianjin, and Harbin, making China one of the most decisive driving forces of passive house in the world. According to the ”13th Five-Year Plan for the development of energy-efficient and green buildings” released by the Ministry of Housing and Urban-Rural Development (MOHURD) in March 2017, “promoting the development of energy-efficient and green building is an objective requirement for the implementation of the national energy production and consumption revolution strategy.”The plan requires to “construct more than 10 million square meters of super-low energy consumption, nearly zero energy consumption demonstration building projects by 2020.” It is expected that the development of passive houses in China will continue to boom in the future.
Thanks to the high vacuum chamber that effectively blocks the thermal transmission, the thermal insulation performance of LandGlass’ tempered vacuum insulated glass product - LandVac® is 2-4 times better than insulated glass and 6-10 times than single pane glass. The properties of LandVac vacuum glass meet all international thermal transmittance requirements on windows and doors for passive houses. Currently, LandVac has been selected in the “Catalog of the Recommended Products for Passive Low-energy Buildings” of MOHURD. In the construction of a passive house project in Urumqi, LandVac is highly praised for its excellent performance in thermal insulation, noise reduction, high transparency with thin thickness and lightweight, and the outstanding safety level as well as in full conformity with the international passive house standards. Following the rapid growth of passive building projects worldwide, there will be more opportunities for the application of tempered vacuum insulated glass. By keeping its leading edge in the industry and continuous innovation, LandGlass will make its due contribution to the promotion of passive low energy consumption buildings, the realization of energy conservation and emissions reduction, and green development.