Measurements on the rate of air exchange in residential buildings have been carried out by the Swedish Institute for Building Research since 1970. The results of an analysis of these measurements are presented in this paper for about 500 buildings not having mechanical ventilation. The studied buildings include one- and two-storey, detached, single- family houses, row houses, and multifamily residential buildings built between 1900 and 1982 and of various design. In some cases, the buildings have been retrofitted by improving the insulation of the attic or the exterior walls.
Laboratories with chemical fume hoods can have HVAC systems designed for variable air volume (VAV) for the optimum in safety and cost savings. Various VAV designs are discussed with their associated advantages and disadvantages. Controls for providing VAV operation of fume hoods are outlined. A computer simulation of the energy usage for constant vs. variable volume hood operation is performed. The energy and cost savings are discussed along with a construction cost comparison of constant volume with variable volume.
Fifty-nine owners/occupants of electrically heated houses in the Denver, Colorado area have, for about ten months, been participating in a study sponsored by the Electric Power Research Institute (EPRI) to determine theeffect of air infi