This guidebook cuts through technical language to explain how owners of one-to-four family dwellings using HUD's popular Section 203(k) rehabilitation mortgage insurance, as well as other HUD programs, can increase the energy efficiency of residential properties. HUD first issued Cost-Effective Energy Conservation Standards for Rehabilitation in 1979. Since then, home construction and energy technologies have advanced--while construction costs and energy prices have increased. The new Secretary's guidelines for cost effective energy conservation recommend energy efficiency improvements to meet the 1992 CABO Model Energy Code, which is required for all HUD-assisted new construction and now is recognized as a goal for rehabilitated properties. The new guidelines incorporate many of the recent technological changes and performance standards and apply them to particular climate zones. The guidebook explains recommended energy measures, conservation terms, and how energy conservation can be cost effective. It also offers Cost- Effectiveness Worksheets and software that can help property owners and remodelers determine the savings from proposed building envelope and equipment measures. Of particular interest is information on qualifying for Energy Efficiency Mortgages (EEM) offered on one- and two-unit houses by participating FHA lenders nationwide. Recognizing that energy conservation measures can significantly lower utility bills and other operating costs for building owners, EEMs enable lenders to liberalize underwriting terms so that borrowers can finance 100 percent of the cost of energy improvements that are deemed "cost-effective" under the new guidelines.