Ventilation: Approved Document F, Volume 2 — Buildings other than dwellings

O N L I N E V E R S I O N A Manual controls A system whereby a ventilation Natural ventilation Ventilation provided by device is opened and closed, or switched on thermal, wind or diffusion effects through doors, and off, or its performance is adjusted by the windows or other intentional openings without occupants of a room or building (see automatic the use of mechanically driven equipment. For the controls). purposes of this approved document, a natural ventilation strategy may include decentralised *Material change of use Defined in regulation 5 as: extract ventilation from rooms where water vapour Where there is a change in the purposes for which or pollutants are likely to be released to minimise or the circumstances in which a building is used, so their spread to the rest of the building. that after that change: Occupiable room A room in a building other a. the building is used as a dwelling, where than a dwelling that is occupied by people, previously it was not; such as an office, workroom, classroom or hotel b. the building contains a flat, where previously it bedroom. The following are not occupiable rooms: did not; bathrooms, sanitary accommodation, utility rooms or rooms or spaces used solely or mainly c. the building is used as an hotel or a boarding for circulation, building services plant or storage house, where previously it was not; purposes. d. the building is used as an institution, where Passive stack ventilation (PSV) A ventilation previously it was not; system using ducts from terminals in the ceiling e. the building is used as a public building, where of rooms to terminals on the roof that extract air previously it was not; to the outside by a combination of the natural stack effect and the pressure effects of wind f. the building is not a building described in passing over the roof of the building. (The stack classes 1 to 6 in Schedule 2, where previously it effect is the pressure differential between inside was; and outside a building, caused by differences in g. the building, which contains at least one the density of the air due to an indoor/outdoor dwelling, contains a greater or lesser number of temperature difference.) dwellings than it did previously; Purge ventilation Manually controlled ventilation h. the building contains a room for residential of rooms or spaces at a relatively high rate to purposes, where previously it did not; rapidly dilute pollutants and/or disperse water i. the building, which contains at least one room vapour. Purge ventilation may be provided by for residential purposes, contains a greater natural means (e.g. an openable window) or or lesser number of such rooms than it did mechanical means (e.g. a fan). previously; Purpose-provided ventilation That part of the j. the building is used as a shop, where it ventilation of a building provided by ventilation previously was not; or devices designed into the building (e.g. background ventilators, PSV, extract fans, mechanical k. the building is a building described in regulation ventilation or air-conditioning systems). 7(4)(a), where previously it was not. *Room for residential purposes Defined in Mechanical supply and extract ventilation regulation 2(1) as a room, or a suite of rooms, Any mechanically driven ventilation that both which is not a dwelling-house or a flat and which continuously supplies outdoor air to the inside is used by one or more persons to live and sleep of the building and continuously extracts indoor and includes a room in a hostel, an hotel, a air and discharges it to the outside. This includes boarding house, a hall of residence or a residential decentralised supply and extract ventilation, and home, but does not include a room in a hospital, mechanical ventilation with heat recovery (MVHR, or other similar establishment, used for patient a mechanical supply and extract ventilation system accommodation. that includes a heat recovery mechanism). 25 Building Regulations 2010 Approved Document F Volume 2, 2021 edition O N L I N E V E R S I O N