The whole house design concept is the hub of green home building. It requires that the home be planned, built and operated as a total system with parts that work together for maximum efficiency, durability, and occupant health and comfort. Teachers and students who accommodate this approach into their education and projects are anticipating the direction of the market and the industry. Students who learn resource efficient design and construction can expect to be more employable. By learning new styles and technologies now and understanding their superiority over the more commonly methods used today, teachers and students may also create the mindset they need to continue to learn and change as conditions that impact building change.

Elements of the Whole House Design

Improvement in building elements and construction techniques allow most modern home building components to be seamlessly integrated into house designs, while improving comfort, health, and aesthetics. The basic elements of a well designed and built house include:

• Planning - Teachers and students should work together on planning entire projects to assure the individual parts of a home complement each other rather than compete or impede each other. Planning helps assure the homeowners goals are met, and the home is built on time and on budget. Before building, the homesite and its climate should be carefully evaluated to determine the optimum design and orientation for the house. Computer software programs can help with these evaluations.
• Thermal Envelope - A thermal envelope is everything about the house that serves to shield the living space from the outdoors. It includes the wall and roof assemblies, insulation, air/vapor retarders, foundation and slab, windows, and weatherstripping and caulking. For example, foundation walls and slabs should be as well insulated as the living space walls. Properly insulated foundations reduce energy use and improve health and comfort, especially if the family uses the lower parts of the house as a living space. In an n insulated basement, for example, even appliances located there can help heat the house.
• Controlled Ventilation - A properly built home is tightly sealed. Consequently, it needs to be ventilated in a controlled manner. Controlled, mechanical ventilation prevents health risks from indoor air pollution, promotes a more comfortable atmosphere, and reduces air moisture infiltration. These reduce the likelihood of structural damage.
• Heating & Cooling Systems - Specifying the correct sizes for heating and cooling systems in airtight, energy-efficient homes can be tricky. Rule-of-thumb sizing is often inaccurate, resulting in wasteful operation. Conscientious builders and HVAC contractors size heating and cooling equipment based on careful consideration of the thermal envelope characteristics. Incorporating ductwork (as well as plumbing and wiring) into a home's conditioned space eliminates heat loss to the exterior and limits the temperature difference at the ducts. Combining this with the placement of the heating/cooling system in a central location enables builders to use shorter duct runs. This can cut material and installation costs by more than 50% and save energy.
• Appliances & Lighting- Although usually more expensive than their counterparts, energy-efficient appliances, fixtures, and lights can pay for themselves with lower operating costs. Major appliances with an Energy Star label exceed federal government minimum efficiency standards by a large percentage.