The increasing number of heat recovery devices in ventilation systems for residential buildings leads to the necessity for a standard test procedure. In this paper the main examination criteria are stated. The test facilities todetermine the efficiencies and the air leakage of heat recovery devices are specified. The test procedure used is described. Results from different heat recovery units indicate the suitability of the developed test equipment.
Energy conservation in dwellings has been realized mainly by tight windows and by improving heat insulation. Increasing damage to the building fabric by humidity and mould has been noticed. But there is no correlation between this damage and the improved insulation. Rather it is caused by too low ventilation rates. This paper deals with these problems in detail. Ventilation rates in the order of 0.5 to 0.8 per hour are assumed to be sufficient to avoid detrimental effects for the building and the inhabitants.
Three blocks of flats on the outskirts of Worms were equipped with a mechanical ventilation system with heat recovery, a mechanical ventilation system, and stack assisted natural ventilation, respectively. Building description, air quality, air change rate, draught protection, noise level, energy balance, individual heating costs, efficiency calculations, planning and installation experience and user behaviour were studied. Systems with heat recovery were found to permit a 15-20 per cent reduction of heat consumption. User behaviour in opening windows is dependent on habit.
This study investigates the structure and availability of ventilation systems in domestic housing. A measurement programme of natural ventilation efficiency was carried out and evaluated. Mechanical ventilation systems were compared. Their suitability for efficient ventilation of various house types is discussed.
Discusses the findings of a nationwide radon survey carried out in W. German houses. The average radon concentration in 6000 houses is 40 Bqm/m3. Treats the incidence of radon in the environment, its sources, the consequences of inhalation of radon, physical processes in room air, and methods of radon measurement.
Recent work has demonstrated the existence of daily and seasonal cycles in attic moisture parameters. Over the course of a day, the attic air humidity may vary by a factor of three, and during the course of a winter there isstorage of perhaps
The principal environmental factors that affect human comfort are air temperature, mean radiant temperature, humidity and air speed. Presents asimplified model of thermal comfort based on the original work of Fanger, whorelated thermal comfort to total thermal stress on the body. The simplified solutions allow the calculations of predicted mean vote (PMV) and effective temperature which (in the comfort zone) are linear in the air temperature and mean radiant temperature, and quadratic in the dew point, and which can be calculated without any iteration.
To measure actual air infiltration in dwellings due to the house and inhabitants it is necessary to measure continuously for several days. This can be done by the constant concentration measuring method. The measurements show that in houses with a reasonably low air infiltration rate (0.2-0.5 h-1) theinhabitant has the major impact (up to 50-75%) on the total air infiltration rate. This must be taken into consideration when designing mechanical and natural ventilation systems.
Presents the results to date of the use of the multiple tracer gas technique to determine interzonal airflow and ventilation rates in large, multicelled buildings like offices. This work is part of a wider project designed toextend knowledge of natural ventilation in all types of buildings other than dwellings.