Single-family house ventilation - Supply Exhaust System system improved, air heating on its way. Smahusventilation - FTX systemen forbattras, luftburen varme pa vag.

Notes that as houses become tighter, adventitious ventilation decreases. Discusses attitudes to varying degrees of tightness. Explains introduction of the supply exhaust system which comprises air supply, air exhaust and heat recovery. Notes requirements for economic use of the system and relates installation costs to potential savings. Tabulates systems currently available in Sweden(December 1980)noting maximum air flow, position of heat exchanger and other factors.