A garage without electrics is a frustrating space — fine for storing boxes, but limited for anything else. Adding a proper electrical installation turns a garage into a workshop, gym, home office, or EV charging point. Most UK homeowners budget between £800 and £2,500 for a competent installation, though the total depends heavily on how far the garage sits from the house consumer unit and how many circuits you need.
All domestic electrical work in England, Wales, and Scotland must comply with BS 7671 (the IET Wiring Regulations, 18th Edition) and, where notifiable, be registered under Part P of the Building Regulations. This is not a grey area — an unregistered installation will cause problems when you sell the property and, more importantly, poses a genuine safety risk.
Typical Cost Breakdown
| Item | Typical cost (inc. VAT) |
|---|---|
| Armoured cable run from house to garage (per metre) | £20–£45/m |
| Sub-consumer unit (4–8 way, RCD/RCBO protected) | £250–£550 |
| Single-phase 32A circuit (e.g. for EV charger or workshop) | £150–£350 |
| Socket circuit with 3–4 double sockets | £150–£300 |
| Lighting circuit (fluorescent/LED batten, 4–6 fittings) | £200–£400 |
| PIR external light | £80–£150 |
| Earth bonding and supplementary bonding | £80–£200 |
| EICR (Electrical Installation Condition Report) | £100–£200 |
For a typical detached garage 8–15 m from the house, a realistic job — armoured cable run, 6-way consumer unit, one ring/radial socket circuit, and a lighting circuit — comes to £1,200–£2,000 when installed by a qualified electrician.
If the garage is integral to the house (sharing a wall), the run is shorter and costs drop to the lower end; a detached garage at the far end of a 30 m garden will sit at the top end or beyond.
What Cable to Use: Armoured vs SWA
For an underground run from house to detached garage, the standard cable is SWA (steel wire armoured) — specifically 6mm² twin and earth for a single-phase supply, buried at a minimum depth of 500 mm under paths and drives and 600 mm under open ground (per BS 7671 Table 52.1). The steel armour protects the cable from accidental damage during future digging.
Overhead cable runs are also permitted but require a minimum height of 3.5 m where people could walk beneath, and the span and sag must be calculated to avoid mechanical failure. Most electricians prefer underground runs for neatness and safety.
An alternative to SWA is conduit with individual conductors, sometimes used where SWA bending radius is a constraint, but SWA is more common for this application.
Sub-Consumer Unit Requirements
Every properly wired garage should have its own small consumer unit (also called a distribution board or sub-board). This serves three purposes:
- Provides local overcurrent protection for each circuit
- Allows isolation of the garage without affecting the house supply
- Provides RCD or RCBO protection as required by BS 7671
Current regulations require consumer units in domestic premises to be housed in a non-combustible enclosure (metal being the most common) following the 2016 amendment to Building Regulations. A plastic consumer unit in a new or upgraded installation is no longer compliant.
A 4–8 way split-load or RCBO consumer unit from a reputable manufacturer (Hager, Schneider, Wylex, MK) costs £60–£150 for the unit itself; installation including wiring in is the bulk of the labour cost.
Lighting Options
For a garage used as a workshop, good lighting is critical. Options in 2026:
- LED batten lights — 5,000–6,500 K colour temperature, 2,000–4,000 lm output per fitting; most cost-effective. A 4 ft twin LED batten (£20–£50) gives approximately 4,000 lm. Two to four fittings suit most double garages.
- LED panel lights — Neater in appearance; better for home offices or gyms.
- High-bay LED — For garages over 3 m ceiling height; not usually needed for domestic.
Switching: a single PIR sensor at the door is convenient for everyday use; a conventional switch is needed if the garage is used as a workshop where constant-on lighting matters. A simple dual switching arrangement (manual or PIR) is easy to wire into the same circuit.
External lighting — a PIR floodlight or wall lantern above the garage door — is typically added to the same lighting circuit or a separate spur.
Sockets and Workshop Circuits
For a workshop, plan socket numbers generously — you will always want more than you expect. Building Regulations do not mandate a minimum socket count in a garage, but a practical layout is:
- One 4-gang socket on each wall (or 2-gang doubles at multiple locations)
- A dedicated 32A radial circuit for a welder, compressor, or large workshop machine
- Sockets at bench height (900–1,000 mm) rather than floor level
For EV charging, a dedicated 32A circuit and Type 2 wall box (£800–£1,200 installed, inclusive of OZEV grant where eligible) is the correct approach — never charge an EV from a standard 13A socket long-term.
Part P and Certification
Under Part P of the Building Regulations, electrical installation work in a garage is notifiable if it involves:
- A new circuit from the house consumer unit
- A new consumer unit or distribution board
- Work in a special location (e.g. within a garage that is damp or has a swimming pool)
In practice, almost all garage electrical work is notifiable. A registered electrician (NICEIC, NAPIT, ELECSA, or SELECT in Scotland) can self-certify their own work, which means they notify the local authority on your behalf and issue an Electrical Installation Certificate (EIC). This is the document you will need when selling the property.
If you have unregistered work done or do DIY wiring, a registered electrician can carry out an EICR to assess the installation, but to regularise it retrospectively you will need to apply for Building Control approval — a more expensive and uncertain process. Do the job right first time.
Useful Checks Before Hiring
- Ask for the electrician’s Part P scheme registration number and verify it on the relevant scheme website (NICEIC Check, NAPIT Find a contractor)
- Confirm they will issue a full Electrical Installation Certificate on completion
- Check whether the quote includes the LABC notification fee (usually £150–£300 if the electrician is not registered to self-certify — a red flag)
- For SWA cable runs, confirm the trench depth and route avoids other buried services (check your utility plans)
Getting the electrics right at the outset saves significant expense later — particularly if you plan to convert the garage or sell the property.
