Converting a London House into Flats: Electrical Requirements

Splitting a London house into self-contained flats is one of the biggest electrical jobs a property can go through. Each flat needs its own supply, meter and consumer unit, and the shared parts of the building need their own landlord supply for lighting and fire alarms. Planning the electrics early helps avoid delays with the network operator and building control. This guide covers the main points. It is general information, not legal advice.

Permissions come first

Converting a house into flats usually needs planning permission and building regulations approval. The electrical design has to fit the approved layout, fire strategy and escape routes. If the property will be rented, check whether licensing applies. Our guide to HMO licence electrical requirements covers shared houses, which have different rules from self-contained flats.

Separate supplies and meters

• Each flat normally needs its own electricity supply and meter so it can be billed separately.
• The network operator may need to upgrade the incoming supply or install a new multi-meter position.
• These applications can take weeks or months, so start them early.
• Plan where meters will go so they are accessible to each flat and to meter readers.

Landlord supply for communal areas

Hallways, stairs and entrances need lighting, emergency lighting and fire alarm power from a separate landlord supply. This supply is usually the freeholder's responsibility once the building is occupied. See our guide on electrical work in leasehold flats for who is responsible for what.

Each flat's installation

Every flat needs a modern consumer unit with suitable RCD protection, circuits sized for its kitchen and heating, and smoke and heat detection. All new work must be certified, and each flat should have its own Electrical Installation Certificate.

Fire safety between flats

Cables passing between flats or through the stairwell must not weaken fire separation. Holes through fire-resisting walls and floors need proper fire stopping, and downlights in some ceilings may need to be fire rated. Building control will check these details.

Certificates for sale or letting

Keep each flat's certificate with the building control completion paperwork. Buyers' solicitors and letting agents will ask for them. See our guide on selling a flat in London.

Book a survey

Energy North Ltd works with owners and developers on flat conversions across North, East and West London with City & Guilds certified electricians. See our EICR service to have the existing wiring checked before design starts.