ABSTRACT
This chapter considers the reasons why good ventilation is required in a dwelling and the role of the various types of ventilation. It illustrates the different ways that effective ventilation can be achieved through both ‘natural’ and mechanical means. Ventilation is the exchange of air between the exterior and interior of the dwelling. There are three types of ventilation: extract ventilation, purge ventilation, and background ventilation. Extract ventilation is needed to remove moisture and/or odours from particular rooms in a house. Purge ventilation is the occasional removal of air at a relatively high rate through the opening of windows or doors, or by mechanical means. Background ventilation is the introduction of fresh air into a dwelling in a continuous stream and at a low rate of air movement. Alternative ventilation systems for dwellings include: passive stack ventilation, continuous mechanical extract ventilation, continuous mechanical supply and extract with heat recovery.
