In 1995 Tacoma Power initiated a test of residential duct sealing to determine the feasibility of a full-scale program to improve the duct system in customer homes with central system electric heat.

In 1997 the State of Wisconsin began searching for low-income programs that were innovative in their approach and which offered the potential to improve or expand program delivery. TecMRKT Works responded to this call with an RFP to implement the first shared-savings pilot weatherization program in the United States. This paper describes the program being tested in Wisconsin and presents some of the early "lessons learned".

In recent years, residential energy conservation research has focused attention on heating system distribution efficiency. Several field studies in the Pacific Northwest have found forced-air heating systems which have a majority of ducts located in unheated buffer spaces can lose as much as 3 0% of the equipment's heating output to duct air leakage and conduction loss. The magnitude of loss can be equivalent to the combined improvements in building shell insulation levels due to updated energy codes.

Ventilation systems for residential buildings can be generally categorized as supply, exhaust, or balanced systems. Subcategories include: integration into central air distribution ducts, or single- or multipoint air distribution; This effort focused on establishing a design methodology for central-fan-integrated supply ventilation systems using an outside air duct to the return side of a central air distribution fan, with a specialized fan recycling control.

The Environmental Protection Agency's (EPA) ENERGY STAR® Homes program seeks to reduce greenhouse gas emissions by encouraging U.S. production home builders to voluntarily improve the thermal quality of their construction by minimizing infiltration, improving insulation, and right-sizing HV AC equipment. Tight homes need active ventilation to maintain indoor air quality, but mechanical ventilation increases initial home cost as well as operating costs.

Simulation analysis suggests that electricity consumption can be reduced up to 40% in existing Florida homes. To test this theory, an all-electric home was located in Miami, Florida upon which to perform a variety of retrofits. The total annual electricity consumption in the one year base-line period preceding the study was 20,733 kWh. Detailed instrumentation and metering equipment was installed in May of 1 995 so that each energy end-use could be evaluated.

While there is no convincing technical basis for current code requirements for crawl space ventilation, most codes still require operable vents and the practice is well established among builders and architects . While the evidence against venting is compelling to many if not most in the research community builders and code officials apparently want to see hard evidence. In this research project I measured weekly energy consumption for space heating for a 1150 square foot home in a climate with 5900 heating degree days.

Natural ventilation in office buildings can sometimes offer other advantages than traditionalmechanical ventilation systems. Often natural ventilation systems are promoted at an earlystage by an architect, but perceived dificulties, e.g. to pre-determine the function of a naturalventilation system, can serve as a barrier and a mechanical system is often chosen instead.