At what height above floor level should a consumer unit be mounted in a dwelling when a new installation is being carried out? The NICEIC provides the answers:
In addition, a consumer unit should not be installed in a location where access to it would be difficult (especially by occupants of the dwelling), as may be the case with a consumer unit in an under-stairs cupboard. Nor should it be installed where it may be susceptible to accidental damage, such as by impact.
Accessibility for operation by users:
Part M of the Building Regulations for England and Wales requires reasonable provision to be made for people to gain access to a building and use its facilities. Guidance on the application of the requirements of Part M is given in 'Approved Document M: Access to and use of buildings'.
Section 8 of Approved Document M, which applies to new dwellings, includes the objective of assisting people whose reach is limited to use dwellings more easily by locating wall-mounted switches, socket-outlets and other equipment at suitable heights so they are easily reachable for use. In this respect, Section 8 indicates that a way of satisfying the requirements of Part M of the Building Regulations is to provide switches and socket-outlets for lighting and other equipment in habitable rooms at appropriate heights between 0.45 and 1.2m from finished floor level.
However, a more limited height range of 0.75 to 1.2m above finished floor level is recommended in BS 8300: 2001 - 'Design of buildings and their approaches to meet the needs of disabled people. Code of Practice'. The recommendation for that range, which is given in clause 10.5.2 of the Code of Practice, relates to simple push button controls, isolator switches and circuit breakers that require limited dexterity.
A general requirement that electrical equipment shall be arranged so as to afford, as may be necessary, accessibility for its operation (which includes considerations of mounting height) is also included in Regulations 131-12-01 and 513-01-01 of BS 7671.
Accessibility for safe working:
Regulation 15 of the Electricity Working Regulations 1989 states that: 'For the purposes of enabling injury to be prevented, adequate working space, adequate means of access, and adequate lighting shall be provided at all electrical equipment on which, or near which, work is being done in circumstances which may give rise to danger.
Amongst the work that generally has to be undertaken at a consumer unit from time to time is measurement of maximum prospective fault current, a test which may give rise to danger. As part of the provisions likely to be necessary to comply with Regulation 15, a consumer unit should be mounted at a height which allows adequate access to be gained to the unit, or work to be carried out safely. Mounting the unit at the height referred to at the beginning of the article (0.75 to 1.2m) is likely to be a way of meeting this safe working height requirement.
Other provisions needed to comply with Regulation 15 (including adequate working space and light) should, of course, not be overlooked.
Mounting a consumer unit at a suitable height for inspection, testing and maintenance is also necessary for compliance with the accessibility requirements of Regulation 131-12-01 and 513-01-01 of BS 7671.
Dwellings located in areas subject to flooding:
Guidance on issues relating to flooding is given in a publication called 'Preparing for floods', a free electronic copy of which can be downloaded by visiting the Government's Building Regulations website.
Preparing for floods recommends that in dwellings located in areas subject to flooding, consumer units (amongst other electrical equipment) should be mounted above the anticipated flood line.
Furthermore, such positioning of a consumer unit would be necessary for compliance with Regulation 522-03-01 of BS 7671. The Regulation requires that a wiring system (which includes the cabling enclosure of a consumer unit) shall be selected and erected so that no damage is caused by condensation or ingress of water during installation, use or maintenance.
In some dwellings, in order to be reasonably assured that the consumer unit will be above the food line, it may be necessary to mount the unit with its operating handles at a height greater than the upper dimension of 1.2m. In such circumstances, the consumer unit should be located so that the amount by which the 1.2m dimension is exceeded is kept to the minimum, consistent with being above the flood line.
