High Performance Construction - Heating and Cooling

Heat flows naturally from a warmer to a cooler space. In winter, the heat moves directly from all heated living spaces to the outdoors and to adjacent unheated attics, garages, and basements - wherever there is a difference in temperature. During the summer, heat moves from outdoors to the house interior. To maintain comfort, the heat lost in winter must be replaced by your heating system and the heat gained in summer must be removed by your air conditioner.

Heating and cooling account for 50 to 70% of the energy used in the average American home. Inadequate insulation and air leakage are leading causes of energy waste in most homes. To read more about how Quail insulate, please click here.

High-efficiency furnaces, in conjunction with a well built house and thermal envelope (sealed and insulated ducts), can reduce heating and energy consumption. At Quail Homes, we use open web floor trusses to enable us to install ducting inside conditioned space. All the ducting are sealed, tested and certified to Earth Advantage standard.

For heating and cooling, Quail Homes installs Bryant hybrid heat system using a heat pump with a high efficient gas furnace with 93% efficiency as our standard. The furnace is also located inside the condition space in the house. To read more about how Quail Homes prevent air infiltration, please click here, and click here to download a more readable Quail High Performance Detail drawing.

There are two types of heat pump: air source and geothermal.

Air-source heat pumps can provide efficient heating and cooling for your home, especially if you live in a warm climate. When properly installed, an air-source heat pump can deliver one-and-a-half to three times more heat energy to a home than the electrical energy it consumes. This is possible because a heat pump moves heat rather than converting it from a fuel, like in combustion heating systems.

Although air-source heat pumps can be used in nearly all parts of the United States, they do not generally perform well over extended periods of sub-freezing temperatures. In regions with sub-freezing winter temperatures, it may not be cost effective to meet all your heating needs with a standard air-source heat pump.

However, new systems with gas heating as a backup are able to overcome this problem. There is also a "Cold Climate Heat Pump" which shows promise, but is currently facing manufacturing problems. In addition, a version called the "Reverse Cycle Chiller" claims to be able to operate efficiently at below-freezing temperatures.

Geothermal heat pumps  (sometimes referred to as GeoExchange, earth-coupled, ground-source, or water-source heat pumps) have been in use since the late 1940s. Geothermal heat pumps (GHPs) use the constant temperature of the earth as the exchange medium instead of the outside air temperature. This allows the system to reach fairly high efficiencies (300%-600%) on the coldest of winter nights, compared to 175%-250% for air-source heat pumps on cool days. While many parts of the country experience seasonal temperature extremes—from scorching heat in the summer to sub-zero cold in the winter—a few feet below the earth's surface the ground remains at a relatively constant temperature. Depending on latitude, ground temperatures range from 45°F (7°C) to 75°F (21°C). Like a cave, this ground temperature is warmer than the air above it during the winter and cooler than the air in the summer. The GHP takes advantage of this by exchanging heat with the earth through a ground heat exchanger. As with any heat pump, geothermal and water-source heat pumps are able to heat, cool, and, if so equipped, supply the house with hot water. Some models of geothermal systems are available with two-speed compressors and variable fans for more comfort and energy savings. Relative to air-source heat pumps, they are quieter, last longer, need little maintenance, and do not depend on the temperature of the outside air. A dual-source heat pump combines an air-source heat pump with a geothermal heat pump. These appliances combine the best of both systems. Dual-source heat pumps have higher efficiency ratings than air-source units, but are not as efficient as geothermal units. The main advantage of dual-source systems is that they cost much less to install than a single geothermal unit, and work almost as well. Even though the installation price of a geothermal system can be several times that of an air-source system of the same heating and cooling capacity, the additional costs are returned to you in energy savings in 5–10 years. System life is estimated at 25 years for the inside components and 50+ years for the ground loop. There are approximately 50,000 geothermal heat pumps installed in the United States each year.We highly recommend geothermal heat pump, when the property size permits.

Tankless Water Heater  is standard equipment at Quail Homes. A tankless water heater has an oversized burner heats water flowing continuously through the unit. Depending on the capacity of the burner and the volume of water running through the unit, tankless water heaters can produce a constant volume of heated water.

Although the burners of tank and tankless heaters are of comparable efficiency, eliminating the tank of stored water and operating the heater only when there is a demand for hot water significantly increases the annualized efficiency of the heater. In general, conversion to a tankless heater will lower water heating energy use by at least 20 percent. Replacing a 20-year-old model with a new tankless one will likely result in savings of 30 percent or more.

Another advantage of eliminating the tank is space savings. A tankless water heater uses much less space than a tank-style heater, and many models can be installed on an exterior wall.

Windows  play a critical role in creating sustainable and high-performance housing. In addition to specifying the right windows to enable more glass without boosting your heating bill, work to get the most out of each window opportunity. Operable windows can be good for crossing ventilation, mitigating the need for cooling energy and mechanical ventilation on summer evenings.

Windows should be selected to manage the quantity of heat loss and solar gain. In a cloudy, heating-dominated marine climate, like ours, it is preferable to use windows with a lower U-factor and a higher Solar Heat Gain Coefficient (SHGC). The U-factor is a measure of heat transfer. The lower the U-factor the better the window performs at stopping heat flow. The SHGC measures how well the window blocks heat caused by sunlight. The lower the rating the less solar heat the window transmits. The IECC, International Energy Conservation Code, requires a window U-value of 0.35 or lower in the marine climate; no SHGC is specified.

At Quail Homes, we install only .30 U-Value or better vinyl windows.

*The above information came from Clark Public Utilities.