Ventilation: Approved Document F, Volume 1 — Dwellings

F1(1) O N L I N E V E R S I O N Section 1: Ventilation provision General 1.1 The aim of requirement F1(1) is to protect the health of occupants of the building by providing adequate ventilation. Without adequate ventilation, mould and internal air pollution might become hazardous to health. NOTE: The guidance in this approved document is not designed to deal with the products of tobacco smoking or vaping. 1.2 The building should provide the ventilation rates given in this section. 1.3 Other ventilation solutions may be used, if it can be shown to the building control body that they satisfy requirement F1(1). 1.4 The ventilation rates set out in this approved document have been designed to meet the indoor pollutant levels in Appendix B where the outside air is of reasonable quality. In areas where the outside air is not of reasonable quality, Section 2 provides guidance on limiting the entry of external air pollutants. Noise 1.5 Mechanical ventilation systems, including both continuous and intermittent mechanical ventilation, should be designed and installed to minimise noise. This includes doing all of the following. a. Correctly sizing and jointing ducts. b. Ensuring that equipment is appropriately and securely fixed, such as using resilient mountings where noise carried by the structure of the building could be a problem. c. Selecting appropriate equipment, including following paragraph 1.6. 1.6 For mechanical ventilation systems, fan units should be appropriately sized so that fans operating in normal background ventilation mode are not overly noisy. This might require fans to be sized so that they do not operate near maximum capacity when in normal background ventilation mode. 1.7 Account should be taken of outside noise when considering whether openable windows are appropriate for purge ventilation. NOTE: Although there is no requirement to undertake noise testing, achieving the levels in the following guidance would ensure good acoustic conditions. The average A-weighted sound pressure level for a ventilator operating under normal conditions and not at boost rates should not exceed both of the following. a. 30dB L * for noise-sensitive rooms (e.g. bedrooms and living rooms) when a continuous Aeq,T mechanical ventilation system is running on its minimum low rate. b. 45dB L * in less noise-sensitive rooms (e.g. kitchens and bathrooms) when a continuous Aeq,T operation system is running at the minimum high rate or an intermittent operation system is running. 6 Approved Document F Volume 1, 2021 edition Building Regulations 2010 O N L I N E V E R S I O N