Heat is always lost through a home's exterior walls because of the conductivity of the materials the walls are built with. In an ACHP home, this heat conduction is reduced by using higher levels of insulation and more efficient structural assemblies. These techniques reduce heat transfer from the heated interior to the cold outside.
Insulation with high R-values and more effective installation techniques are both very important in cold climate homes. In the ACHP Fair House, computer analysis helped to optimize the placement and installation of the insulation materials used throughout the home.
Most homes the size of the ACHP Fair House have air leakage equaling a five-square-foot hole in the wall. While some leakage is inevitable, the air leakage in this ACHP home equals less than one square foot. The difference lies in the continuous air/vapor retarder installed throughout the exterior envelope. Each retarder seam laps and is sealed to the next, and is also sealed around outlets, switches, and plumbing.
Quite a number of advances have been made in this area. Many appliances now use only one-third the energy used by appliances available a few years ago.
In heat loss terms, windows are holes in your home. Therefore, the better your windows are, the better your home will perform. The ACHP Fair House has windows that cut heat loss to half that of standard double pane windows. These windows, in combination with proper home ventilation, will virtually eliminate interior icing and condensation, even at subzero temperatures.
Air leakage is minimized in an energy-efficient house through the use of continuous, sealed air/vapor retarders. It is important, though, that air move throughout the home at an even rate. This way, one room does not become stale while another is always drafty. The ACHP Fair House's balanced ventilation system brings in fresh air, distributes it evenly throughout the home, and exhausts the stale air. Through the use of an HRV, like the one installed in this home, some of the heat from the outgoing air is extracted to warm the incoming air.
Without an efficient heating system, as much as 30% to 50% of your energy dollars are going right up the chimney. High efficiency heating equipment can reduce these chimney losses to 5%. In addition, all air that is used in the combustion process is drawn from outside of the house to avoid sending your heated interior air up the chimney. This also assures adequate venting of combustion products and no backdrafting from combustion appliances.
The Alaska State Fair House serves as a permanent exhibit, designed and built with the latest in energy-efficient building technologies. It proves that northern homes can be attractively designed and filled with natural light, while still being energy-efficient. The ACHP Fair House was built with many different methods of energy-efficient construction, not promoting any one specific product or construction technique. This was done to show that there are many different materials and construction techniques available for energy-efficient home building.
There were sixteen different wall construction methods used within this home. The south gable wall, and the east and west walls, are various stressed skin panels. The remaining four wall sections are each wood-framed, using different methods, with three different types of insulation within them.
The main roof is composed of stress skin panels. The two gables are conventional framing with four different insulation combinations.
There are five types of windows throughout the house, with different glazings and coatings, demonstrating varying R-values (R = resistance to heat flow).
As with all ACHP certified homes, a continuous vapor retarder was installed within all exterior walls and the roof. This creates a very airtight structure so that air leakage can be minimized and controlled. Controlled, mechanical ventilation is necessary in energy-efficient construction for indoor air quality, as well as to ensure the durability of the structure. In this home a heat recovery ventilator (HRV) was utilized to fulfill the ventilation needs. Stale indoor air, whether wet or dry, indicates that the home suffers from insufficient fresh air circulation. Keeping air trapped inside the home allows the build up of unhealthy air (including tobacco smoke, cooking fumes, airborne allergens and volatile organic chemicals emitted by furniture, paint and floor coverings). If the home is not airtight, though, uncontrolled air leaks in the walls allow dust to collect on interior surfaces and serve as a path for water vapor migration into the wall cavities. Because an ACHP home is built using draft-free construction, with controlled, mechanical ventilation, there are none of the health risks caused by poor indoor air quality nor the energy-loss and structural risks caused by leaky walls. An ACHP home has warm, fresh air year-round, with controlled humidity levels.
All of these features, along with the alarm system, a control system for monitoring the energy components, energy-efficient lighting, and water conserving plumbing, are exhibited and displayed throughout the home.
The cost of heating this home with a high-efficiency gas heating system, for a six-month period in 1991 was $245.68 (this was during the construction phase and a plywood door was being used). For the following twelve-month period in 1991 - 1992, the bill was only $204.72.
