This publication provides information about present uses of solar energy for space, water, and swimming pool heating that are practical for the San Francisco Bay area. It attempts to provide interested persons with the information needed to make decisions regarding installations of solar heating systems. The point of view taken is that any structure can be retrofitted with a solar heating system. Chapter titles include: (1) Solar Basics; (2) Energy Estimating and Conservation; (3) Solar Prospecting; (4) Retrofit Systems; (5) Estimating Performance; (6) Solar Economics; (7) Getting Started; and (8) Further Information. Many different adaptations of both passive and active solar heating systems are diagrammed and explained. Installation tips and precautions are also included. Worksheets are provided, along with completed examples, to aid in estimating the cost of installing solar heating systems. Additional sources of information are suggested to the interested reader. Even though this publication refers to the San Francisco area, the solar retrofitting information given applies almost anywhere. (MR)