heat loss

Examines the fundamental building heat loss calculations. Points out some anomalies in the traditional view of room thermal behaviour. Treats equations governing room heat loss taking account of the temperature of the walls and the environmental temperature. Justifies the use of the environmental temperature rather then the air temperature. Examines the heat loss due to ventilation. Discusses the use of the temperature ratio.

Gives a method of calculating the rate at which air enters a building, and how long it takes to reach a steady state, given the area of the door, the volume of the building and the air change rate caused by infiltration when the door is shut. Resulting heat losses are unacceptably high, but not as high as claimed by manufacturers of door closing devices.

Makes an inventory of different outside wall structures and details their construction with respect to heat losses. Notes that in some countries, little consideration is made of energy losses and that Building Regulations in Sweden are strictest.

Outlines ventilation needs to show that odour dilution and moisture control are the major winter factors. Detailed studies on 24 well insulated houses show that window opening habits are clearly linked to outdoor temperature, more windows being opened in milder weather.< Shows from energy input analysis that space heating only provides a quarter of the total heat, the remainder coming from casual sources. Analysis of energy loss suggests that a third of the losses are attributable to ventilation, the remainder through the building fabric.

Reports on seminar at University of Lund, Sweden and the factors affecting U-value: radiation, thermal capacity, moisture in materials, evaporation of precipitation moisture, convection, air movement, quality of work, cold bridges, ageing, air gaps.

Describes the relationship between wind flow round a building and heat loss from it. The relative merits of numerical and wind tunnel models are discussed and various numerical techniques, including the vortex method and the control volume method, are examined.

There are two types of air movement in the shell of a building - movement along the insulation as in cavity walls and movement through the insulation. Generally the heat losses due to the faults in the inner lining of the vapour barrier and the consequential air movement through the shell are much bigger then losses due to faults in the insulation - they cannot be compensated for by using tighter wind protection.

Analyses an infiltration heat loss calculation in accordance with Standard CSN 06 0210, with regard to the minimum air exchange rate (0.3 ach/hr). Concludes that aeration through windows should be graded for buildings which are differently located in the landscape and thus differently exposed to the wind effect.

This parameter study with the IMG calculation model for ventilation is an attempt at forming some background for decisions relating to the preparation of a standard in the Netherlands. From the results one can see that air tightness and the heat loss caused by infiltration cannot be considered as a simple linear relationship .

Presents the results of an investigation carried out on behalf of the Swiss Ministry for Environmental Protection. The main aims were to find acalculation method for the annual energy demand of a building which takes into account solar heat gain and which generates data permitting the effect of thermal protection regulations on energy consumption to be evaluated. Treats the effect on transmission heat loss of outside walls of absorbed solar radiation, the specific heat loss of typical dwellings, reference years based on weather data for energy consumption calculations.