THREE APPROACHES WERE USED TO FACILITATE THIS ANALYSIS OF THE AMERICAN SOCIETY OF HEATING, REFRIGERATION, AND AIR CONDITIONING ENGINEERS' (ASHRAE'S) STANDARD 90-75: (1) THE STANDARD PRESCRIPTIVE/PERFORMANCE APPROACH, BASED ON AN ELEMENT-BY-ELEMENT DESIGN ANALYSIS; (2) THE SYSTEMS ANALYSIS APPROACH, ALLOWING FOR COMPLIANCE IF THE BUILDING'S ENERGY CONSUMPTION IS EQUAL TO OR LOWER THAN THAT ACHIEVABLE THROUGH THE FIRST APPROACH; AND (3) THE ENERGY AUGMENTATION APPROACH, ALLOWING FOR THE USE OF SOLAR-POWERED OR WIND-POWERED SYSTEMS. ASHRAE 90'S IMPACT ON THE CONSTRUCTION INDUSTRY IN GENERAL, AND ON ENERGY CONSUMPTION, INITIAL COST, AND OPERATING COSTS OF PROJECTS WAS DETERMINED ON THE BASIS OF ITS EFFECT ON EACH OF THE FOLLOWING TYPES OF BUILDINGS IN FOUR MAJOR CENSUS REGIONS: SINGLE-FAMILY DETACHED RESIDENCE, LOW-RISE APARTMENT BUILDING, OFFICE BUILDING, RETAIL STORE, AND SCHOOL BUILDING. A TOTAL OF 20 PROTOTYPICAL BUILDING TYPE/LOCATION PROJECTS WERE INVESTIGATED, WITH STUDY RESULTS SHOWING THE MAXIMUM IMPACT IF THE STANDARD WERE ADOPTED. THE STUDY'S MOST IMPORTANT CONCLUSIONS FOCUS ON BUILDING ENERGY CONSUMPTION, PHYSICAL CHARACTERISTICS, BUILDING ECONOMICS, NATIONAL ENERGY CONSUMPTION, BUILDING MATERIALS AND BUILDING EQUIPMENT MARKETS, KEY INDUSTRY PARTICIPANTS, AND BUILDING HABITABILITY. APPENDED MATERIAL INCLUDE THE DESIGN CAPACITIES AND ENERGY CONSUMPTIONS OF PROTOTYPICAL BUILDINGS, COST INDEXES, AND THE EFFECTS OF RELATIVE HUMIDITY ON HEALTH. TABULAR DATA, CHARTS, GRAPHS, FOOTNOTES, AND A BIBLIOGRAPHY ARE INCLUDED. (WJR)