occupancy effects

Suggests that occupants need domestic competence to attain designed savings envisaged in project. Reports sociological study to: investigate and map out individual behaviour patterns in relation to actual energy savings; follow up use of technical installations with respect to reactions and experience; assess reaction to living in airtight house with high technical standard. Describes interview techniques for assessing anything related to energy savings. Analyses use of technical equipment, domestic electricity and hot water.

With improved thermal protection of buildings proportion of ventilation heat loss has grown until it now accounts for 50% and more of total building heat losses. Since ventilation cannot be reduced below certain limits for comfort and hygenic reasons, selection of appropriate type of ventilation system is increasingly important to control heat losses. Describes characteristics and consequences for heat energy consumption and hygiene of constant ventilation and abruptly increased ventilation such as window opening etc.

Shows need for intermittent high ventilation in dwellings to remove water vapour and odours. Suggests openable windows as the simplest and most common method of ventilation control. Gives air-change-rates in two british houses using carbon dioxide andnitrous oxide as tracer gases, showing the effect of opening windows. Shows that increase in ventilation rate caused by opening windows can be tenfold and is not confined to the room with the open window. Closing of internal doors has a significant effect. Describes investigation of air flow within rooms using smoke.

Proposes general method to identify contribution of resident-dependent effects to observed variability of energy consumption in similar houses. Method assumes that in addition to records of energy consumption over time, there is access to information about date of change of occupants. For data on TwinRivers, New Jersey, shows that the role of resident-dependent effects dominates the role of effects that depend on structural variations over which residents have no effective control.

Reports two-year programme to evaluate the effect of air infiltration on the heating needs of 29 electrically heated homes. Air-change rates before and after retrofitting tominimize infiltration were measured by a pressure method and heat energy consumption and occupancy effects were monitored. Thirty similar homes were also tested for infiltration and retained as controls.< Describes the retrofit methods, their effect upon the induced air infiltration, the other data which are being collected, and the data analyses which are expected at the completion of the programme.

States that ventilation needs can be identified from a study of people's behaviour. Reports results of regular systematic observations of open windows in a group of scottish houses which confirmed earlier work in Britain. Finds that the number of open windows is a direct function of outdoor temperature or moisture content and was also influenced by air speed with a smaller number of windows being opened in windy weather. Large families opened their windows more frequently than small families. Suggests that moisture control may be the main motivation for opening windows.

Outlines ventilation measurements being made on two storey semi-detached houses using helium as a tracer gas. Describes measurement of decay rates in single rooms, the recirculation between two rooms and by summation the ventilation rate of thewhole house. Describes installation used to measure ventilation rates when homes are occupied without interfering with the normallife of tenants.

Examines air flow into air-conditioned buildings caused by opened external doors in summer. Firstly the wind velocity through open doorways was measured using puffs of smoke inentrance hallways, finding that velocities varied from 104 ft/min to 350 ft/min with a mean of 265 ft/mins. Then tests were made on the air inflow when a swing door was opened and closed. Finally tests were made of the air flow due to operating revolving doors. Results for various types of entrances are displayed in a table.

Gives results of measurements of air-change rates and heat loss in occupied and unoccupied houses on two sites, one exposed and the other sheltered. Observations of the wind pressures on the houses and of the window-opening habit of the occupants are discussed. These are used in conjunction with the results of a regional survey of the temperatures maintained and the window-opening habits in local authority houses to extend the application of the results of other housing.

Gives survey of humidity in Canadian homes indicating that humidity depends primarily on outside conditions but is influenced by the ventilation habits of the occupants and moisture storage by hygroscopic material. The difference between indoor and outdoor humidity ratios gave an estimated ventilation rate of 0.44 charges per hour. Resultant indoor relative humidity level is between 25 and 30% on average and approaches the maximum humidity attainable without condensation on double-glazed windows.