Ventilation: Approved Document F, Volume 1 — Dwellings

A O N L I N E V E R S I O N Purpose-provided ventilation That part of the Ventilation The supply and removal of air (by ventilation of a building provided by ventilation natural and/or mechanical means) to and from a devices designed into the building (e.g. background space or spaces in a building. It normally comprises ventilators, extract fans, mechanical ventilation or a combination of purpose-provided ventilation and air-conditioning systems). infiltration. *Room for residential purposes Defined in Wet room A room used for domestic activities regulation 2(1) as a room, or a suite of rooms, (such as cooking, clothes washing and bathing) that which is not a dwelling-house or a flat and which produce significant amounts of airborne moisture, is used by one or more persons to live and sleep e.g. a kitchen, utility room or bathroom. For the and includes a room in a hostel, an hotel, a purposes of Part F of the Building Regulations, boarding house, a hall of residence or a residential sanitary accommodation is also regarded as a wet home, but does not include a room in a hospital, room. or other similar establishment, used for patient Whole dwelling ventilation (general ventilation) accommodation. Nominally continuous ventilation of rooms or Sanitary accommodation A space containing one spaces at a relatively low rate to dilute and remove or more flush toilets (WCs) or urinals. Sanitary pollutants and water vapour not removed by accommodation containing one or more cubicles extract ventilation, purge ventilation or infiltration, counts as one space if there is free circulation of air as well as to supply outdoor air into the dwelling. throughout the space. Shared communal rooms Rooms in buildings containing dwellings, which provide facilities for the residents. For example, a laundry room, occupied lobby or gym. This does not include areas used solely or principally for circulation in buildings containing dwellings, including corridors or lift lobbies. Surface water activity A measure of the availability of water to micro-organisms. Surface water activity is determined from the ratio of the vapour pressure of the water in the substrate to the vapour pressure of pure water at the same temperature and pressure. This ratio, in steady-state conditions, is numerically equal to the equilibrium relative humidity of the air, except that the latter is commonly expressed as a percentage. Thermal envelope The combination of thermal elements of a building which enclose a particular conditioned indoor space or group of indoor spaces. Utility room A room containing a sink or other feature or equipment that may reasonably be expected to produce significant quantities of water vapour. 38 Approved Document F Volume 1, 2021 edition Building Regulations 2010 O N L I N E V E R S I O N