Garden rooms and home offices have become a big part of how people use their homes. So has the garden itself: lighting, a hot tub, outdoor sockets for the lawnmower, power to the shed. All of it needs electricity, and electricity outdoors needs a bit more thought than inside.

This is a guide to planning outdoor electrics properly, from a simple outside socket to a fully powered garden office.

Why outdoor electrics are different

Outside, everything is exposed to rain, frost, condensation, garden tools, roots and the occasional spade. Electrical work outdoors needs:

Suitable cables, protected against damage
Weatherproof fittings rated for outdoor use
RCD protection, to cut the power quickly in the event of a fault
Correct earthing, which can be a specialist question for outbuildings

The wiring regulations have specific requirements for outdoor installations. It's one area where DIY or extension leads strung across the lawn really aren't a good idea.

Powering a garden room or office

A garden room is often a small building in its own right. Typical needs:

Sockets for a computer, monitor, phone chargers
Lighting, inside and out
Heating: often an electric heater or air conditioning unit
Data: Wi-Fi extension or a cable for internet

Supply. Power usually runs from the house's consumer unit, via a suitable cable, to a small consumer unit in the garden room. That gives the building its own protection and circuits.

Cable route. Usually buried in a trench, with the cable protected and the route marked. Depth and protection need to be appropriate to avoid damage from digging. In some gardens it can be run along a wall or fence in suitable protection.

Distance. The further the garden room is from the house, the more the cable size matters, so the voltage doesn't drop too much and the protection still works correctly.

Load. An office with a laptop is light. A gym with a treadmill, heating and air conditioning, or a garden room with a hot tub nearby, needs much more. Tell your electrician what's going in there.

Earthing

Outbuildings can have particular earthing requirements, depending on the type of supply to your house and the construction of the building. This is a technical design decision for your electrician. It's one of the reasons garden room electrics should be designed, not improvised.

Outdoor sockets

Handy for mowers, hedge trimmers, pressure washers and Christmas lights. They should be:

Weatherproof and rated for outdoor use
RCD protected
Positioned where they're useful but not in the way of water or splashes
Lockable or switchable from inside if you're worried about tampering

Garden lighting

Options range from simple wall lights to full landscape lighting:

Wall and security lighting for paths, doors and parking areas, often with PIR sensors
Path and step lighting for safety
Feature lighting for trees, planting and seating areas

Low-voltage systems can be a good option for some garden lighting. Whatever the system, plan cable routes before the landscaping is finished.

Hot tubs

Hot tubs typically need a dedicated supply with appropriate protection, sized for the tub's load. Check the manufacturer's requirements and get the supply designed properly. Don't plug a hot tub into an outdoor socket on an extension lead.

EV chargers

If you're running cables outside anyway, think about whether you'll want an EV charger on the drive in the future. Planning the route now can save trenching twice.

Is your installation up to it?

Adding a garden room, hot tub or EV charger adds load to your home's installation. Your electrician will check:

Consumer unit space and protection
The supply capacity to the house
Earthing arrangements

Sometimes a consumer unit upgrade is the sensible first step.

Planning and building warrant

Many garden rooms in Scotland don't need a building warrant if they're below certain sizes and meet the conditions, but some do, depending on size, location, use and whether people will sleep in them. The electrical work must still meet the wiring regulations and building standards. Check the building's requirements with your council or supplier.

Timing

If a garden room is being built, the electrician should be involved:

Before the base goes in, if cables need to come up through the floor
Before landscaping, so trenches can be dug and backfilled before paving and lawns
After the building is up, to fit out the inside

Certification

Once complete, you should receive an Electrical Installation Certificate showing the work has been designed, installed and tested correctly. Keep it.

Cost

We don't publish fixed prices. The main factors are the distance from the house, the cable route and trenching, the load required, the number of sockets and lights, and whether the consumer unit needs upgrading.

FAQ

Can I run an extension lead to my garden room?

It's not a safe permanent solution. A garden room needs a properly installed supply with suitable protection.

How deep does an armoured cable need to be buried?

It needs to be buried at a depth and with protection suitable to avoid damage. Your electrician will design the route and depth to suit your garden.

Does a garden room need its own consumer unit?

Often, yes. A small consumer unit in the garden room provides local protection and circuits.

Do outdoor sockets need RCD protection?

Yes. RCD protection is a key safety requirement for outdoor sockets.

Can I get power to my shed as well?

Usually, yes. A shed can often be supplied as part of the same installation as a garden room or outdoor lighting.

Tell us about the garden room or outdoor circuit through the contact form, or see our electrical installation services.

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Outdoor Electrics and Power to a Garden Room: Doing It Safely in Edinburgh