Bathroom Building Regulations UK: Electrics and Ventilation

Do you need building regulations approval for a bathroom?

It depends on the room and the work. Refitting a bathroom with new units and fittings does not generally need building regulations approval, although drainage or electrical work in the refit may, the Planning Portal says. A bathroom in a room where there was not one before is likely to need approval for its ventilation, drainage, structural stability, electrical and fire safety, it says.

GOV.UK lists installing a bathroom that involves plumbing, and changing electrics near a bath or shower, among the alteration projects that need approval.

Bathroom job	Building regulations approval	Source
Refitting a bathroom with new units and fittings	Not generally needed	Planning Portal
Drainage or electrical work in a refit	May be needed	Planning Portal
A bathroom in a room where there was not one before	Likely to be needed	Planning Portal
Installing a bathroom that involves plumbing	Needed	GOV.UK
A new circuit, such as one for a shower	Needed, unless self-certified	Planning Portal
An extra power or lighting point around a bath or shower	Needed, unless self-certified	Planning Portal
Altering the ground floor toilet in a home built after 1999	May be needed	Planning Portal

Notifiable electrical work in a bathroom

The Planning Portal lists three kinds of notifiable electrical work: a new consumer unit or fuse box; a complete new circuit, such as a new circuit for a shower; and alterations to existing circuits, such as an extra power point or lighting point, but only in special locations. In England, it says, special locations are the spaces around baths and showers.

The special location around a bath or shower

Regulation 12 of the Building Regulations 2010 defines a special location in two parts. The first is the space around a bath tap or shower head in a room containing a bath or shower, from the finished floor up to 2.25m, or to the shower head where it is fixed higher, and 0.6m out from the edge of the bath tub or shower tray, or 1.2m from the centre of the shower head where there is no tub or tray. The second is a room containing a swimming pool or sauna heater.

Who can self-certify bathroom electrics

An installer registered with a competent person scheme can self-certify that the work complies with the building regulations, the Planning Portal says, and it is best to use one. If the installer is not registered, a building control body or, in England only, an electrician registered with a third-party certification scheme has to inspect, approve and certificate the work, the Planning Portal says. Nottingham City Council says electrical work and gas installations need no approval provided a competent person carries them out.

Bathroom extractor fan and ventilation rules

Any new bathroom, shower room or toilet should have a means of extract ventilation to reduce condensation and remove smells, the Planning Portal says. When you refurbish a bathroom, any existing extract ventilation has to be retained or replaced, it says, but where there was none, you need not add one. The Planning Portal gives a bathroom, with or without a WC, 4,000mm² equivalent area of background (trickle) ventilation.

Toilet building regulations and ground floor toilets

A toilet, unlike a bathroom, can have purge ventilation instead of extract ventilation where security is not an issue, the Planning Portal says, meaning an opening window or door on an external wall that meets Approved Document F. The opening has to be at least 1/20th of the room’s floor area for a window that opens more than 30 degrees, or 1/10th for one opening 15 to 30 degrees, and a window opening less than 15 degrees does not count. Check that the ventilation is in the price quoted for a new downstairs toilet.

Any home built after 1999 will have a ground floor toilet designed for visiting wheelchair users, the Planning Portal says. A refit should not remove that toilet or make it any less accessible, and a building regulations application may be required to alter it.

Timber floors and the weight of a full bath

A new bathroom suite on a floor of timber joists and boards carries a significant risk of the bath overloading the floor once it is full of water and in use, the Planning Portal says. Where a room’s use changes and the load on the floor could change significantly, strengthening may be necessary. A structural engineer or surveyor can assess the floor and produce the paperwork a building control body will require before the work starts.

Planning permission and listed buildings

Building regulations approval is different from planning permission, and you might need both, GOV.UK says. A planning application for installing a bathroom is generally not required unless it is part of a house extension, the Planning Portal says, though in a listed building you should consult the local planning authority.

Nottingham City Council says most building work to a listed building, internal and external, needs listed building consent, and its My Property tool shows whether a property is listed.

Checklist for a new bathroom, en suite or downstairs toilet

Nottingham City Council says the building regulations will probably apply to fittings including washing and sanitary facilities, hot water cylinders, and foul water and rainwater drainage.

Who is responsible for building regulations approval

If you are employing a builder, the responsibility will usually be theirs, but you must confirm this at the very beginning, Nottingham City Council says. If you are the owner and the work does not follow the regulations, it is you who will be served with an enforcement notice.

GOV.UK says the person doing the work could be prosecuted and fined if they do not comply with the building regulations, and that without approval you will not have the certificates of compliance you may need when you sell your home.

Among the ten Nottingham bathroom fitters we compare, Goldswan Bathrooms in Arnold says its own team does the plumbing, electrics, tiling, plastering and flooring, with one project manager as the point of contact. Whoever you hire, make who applies for approval one of the questions to ask a bathroom fitter before you accept a quote.