Energy use in buildings and design requirements : the energy costs and financial costs of building materials, structures and space heating, the detailed patterns of use of heating systems in dwellings, and their interactions : their implications for design
The primary energy costs of building materials and structures are discussed and comparisons are made between typical dwelling types. The economics of alternative wall, roof and floor constructions, providing various levels of insulationy are examined. Costs are assessed for a number of periods from 1970 to early 1980 for heating by gas and night rate electricity. The effect of price changes-on the economic attractiveness of insulation is investigated and the likely effects of future price rises are considered. It is concluded that, in certain circumstances, higher levels of insulation than those normally used in the UK have been economically attractive for the last few years and may possibly become more so. A survey of over fifty local authority houses with central heating, carried out by the author in Spring 1978, is described. Three types of houses of similar size were involved, having gas-fired 'wet' systems, and ducted warm air heating from electric storage and gas-fired units respectively. The survey was designed to determine certain aspects of occupant behaviour relevant to fuel consumption. Using regression techniques, relationships are obtained which explain more than two thirds of the variance of mean useful energy input rate between the houses of a given type in cold weather in terms of hours of use of central heating window opening habits, and for warm air heating, the closing of outlet registers. It was also revealed that for the house types with gas-fired heating the number of hours of use of the central heating was strongly influenced by household size and occupancy patterns. The implications for building design of the effects of occupant behaviour and of financial and energy costs are discussed.