Describes a programme of ventilation measurements performed on a group of energy efficient houses built in the mid-1970's and situated in Abertridwr, S.Wales. Pressurization, tracer decay and British Gas autovent techniques were employed. Results show satisfactory whole-house ventilation rates (0.5 ac/h), but the living room and bedrooms had very low ventilation rates. Some cases showed serious condensation. "Trickle" ventilation installed in 18 of the houses improved internal ventilation patterns and condensation levels were substantially reduced.
Traces the relationship between ventilation needs and methods and the growth of civilization. Describes the development of ventilation methods and assessment of air quality, especially since the Industrial Revolution. Questions whether currently accepted ventilation criteria are still valid, andsuggests that ventilation is only one of several means of ameliorating the internal environment.
Describes a simple method of controlled ventilation comprising an extract system and air inlets. The extract system is effectively a flue connecting to vents in the kitchen and bathroom and relying on thermal differences and the wind to create air flow, air enters the house via slot vents over windows. Theproposed system has been installed in a timber framed house.
Outlines project where 25 representative dwellings from Birmingham Local Authority Housing stocks were monitored before and after energy retrofitting. Findings are presented as a set of case studies encompassing both fabric and infiltration measures. Suggests that simple energy conservation measures are successful but that more sophisticated combinations tend to under-achieve. Ventilation changes in several cases are impaired by increased use of windows and/or permanent ventilation. Where these effects are'nt operating, reductions of between 0.3 - 0.6 ac/hr appear typical.
Discusses air quality and the related definitions of ventilation efficiency. Suggests a definition of efficiency for ventilation systems in residential buildings that takes into consideration how ventilation air spreads within a dwelling. Measurements of the efficiency for exhaust, supply and combined systems show that for combined and supply systems the highest efficiency occurs in those parts where the air is supplied.
Detailed studies of public sector modernisation programmes show that the principal problem resulting from lack of thermal insulation and inappropriate methods of heating and ventilation is condensation and mould growth. Gives the optimum air change rate (for dwellings with particular heat loss characteristics) at which the heat input necessary to prevent the RH rising is at a minimum. The resulting temperatures are too low to be considered comfortable, so air change rates need to be less than the optimum.
Examines several ventilation strategies in tight houses for both impact on the total ventilation and effect on the energy balance of the system. Uses the single-zone infiltration model developed at LBL as part of the calculation of total ventilation load. Strategies covered include natural systems such as ventilation stacks as well as mechanical systems such such as air-to-air heat exchangers and exhaust fans with and without heat pumps.
Describes project on experimental housing of a new type built by Swedish manufacturers employing light, timber construction. Good airtightness and careful work results in the lowest total cost. Investigation shows results of profitability of various investments. Illustrates energy balance for housing discussed.
Describes the measurement of infiltration and air change rates in one flat in an apartment block containing 24 flats. Gives the general principles of the pressurization method and tracer gas method for measuring air change rate and infiltration rate. In this situation uses N2O as the tracer gas and measures concentrations with an infra-red gas analyser. Measures the effects of opening and sealing windows, and of closing internal doors on the air change rate and air movement in the flat.
Surveys the Danish energy-saving program in the Ministry of Housing 1975-1987. Covers grant schemes, energy conserving measures in public and state buildings from 1975, control schemes for heating installations, and building regulations. Includes as an appendix a copy of the 1982 Act on the Reduction of Energy Consumption in Buildings.
Login