Whether you’re converting a shed into a workspace, building a garden studio, or adding a new garage or workshop, one thing’s for sure — you’ll need safe, reliable electricity.
And while it might sound simple — “just run a cable from the house” — getting power to an outbuilding isn’t a DIY weekend job. It’s a proper electrical installation that needs the right design, materials, and certification.
So, what’s actually involved? Let’s walk through the process so you know exactly what to expect.
Step 1: Assessing what you’ll be powering
Before any cabling goes in, your electrician will want to know how you plan to use the building.
Is it just lighting and a few sockets for laptops and printers? Or are you running power tools, heaters, or a fridge? The type and quantity of electrical load determine everything — from cable size to protection requirements.
For example, a small garden office in Hartley Wespall might only need a 20A supply. But a workshop in Upton Grey with machinery or heating could require a 40A feed or even a small consumer unit of its own.
Getting this right at the start ensures the installation is both safe and futureproof.
Step 2: Planning the cable route
Power to outbuildings is usually supplied via an armoured cable (SWA), buried underground or securely clipped to a wall or fence.
If it’s buried, the trench needs to be at least 450mm deep in a domestic garden and protected with warning tape above the cable. It’s a proper bit of groundwork, not just laying an extension lead in a flowerbed.
Where possible, your electrician will plan the route to minimise digging and avoid crossing driveways or tree roots. In Old Basing and Sherfield-on-Loddon, where gardens can be large, it’s often worth running a spare conduit or data cable alongside — handy for future upgrades like Wi-Fi or CCTV.
Step 3: Protecting the circuit
At the main house, your electrician will connect the new outbuilding supply to your consumer unit (fuse board).
If your existing board doesn’t have spare capacity, or lacks modern RCD protection, this may need an upgrade or additional circuit.
The circuit feeding the outbuilding must have:
- RCD protection to prevent electric shock
- Appropriate fuses or breakers rated for the cable and load
- Proper earthing arrangements, especially if the outbuilding has metal cladding or water pipes
Depending on the distance, a voltage drop calculation is carried out to make sure everything runs efficiently and safely.
Step 4: Installing sockets, lighting, and switches
Once the power reaches the outbuilding, your electrician will fit a small consumer unit (also known as a sub-board) to distribute power to sockets, lights, heaters, or other equipment.
Inside the building, wiring can be run in trunking or conduit for neatness and protection, particularly in workshops or garden offices that might see wear and tear.
Popular additions include:
- LED strip or panel lighting for energy efficiency
- External lights with PIR sensors for security
- Heating controls or underfloor heating circuits
- Data cabling or Wi-Fi boosters for home offices
Every installation is tailored to how you’ll actually use the space — not just what’s easy to install.
Step 5: Testing and certification
Once the installation is complete, your electrician will carry out a full set of electrical tests to confirm the system is safe, compliant, and correctly earthed.
You’ll then receive two key documents:
- An Electrical Installation Certificate (EIC) — confirming the work meets the BS 7671 Wiring Regulations.
- A Building Regulations Compliance Certificate (if applicable under Part P) — sent by the NICEIC or NAPIT if your electrician is registered.
These certificates are important. They protect you legally, help with insurance, and will be needed if you ever sell your home.
Step 6: Optional extras for comfort and efficiency
Modern outbuildings aren’t just powered sheds. Many are fully equipped garden rooms, gyms, or studios — and can benefit from a few smart upgrades:
- Smart lighting or thermostats you can control from your phone
- Solar panels or battery backup to reduce running costs
- Insulation-friendly fittings to prevent heat loss
- External power points for garden tools or EV charging
If you’re building from scratch, planning these early can save time and money later.
Why use a professional electrician
Running power to an outbuilding is classed as notifiable electrical work under Part P of the Building Regulations. That means it must be done by a registered electrician who can self-certify the work — or it has to be inspected by your local council’s Building Control department.
At GU Solutions, we handle the whole process for you.
We’re NICEIC Approved Contractors with over 20 years of experience installing safe, certified power supplies for garden offices, workshops, and outbuildings across Basingstoke, Dummer, Cliddesden, and the surrounding Hampshire villages.
We’ll take care of:
- Design and load calculations
- Cable routing and trenching
- Consumer unit connections and protection
- Testing, certification, and compliance paperwork
So you get a clean, safe installation that’s built to last — with full documentation and support.
Book your outbuilding power survey
If you’re planning a garden office, workshop, or outdoor studio, let’s make sure it’s powered properly.
Call GU Solutions on 01256 473326 or send us a message to book your site survey and quote.
We’ll design a system that fits your needs, complies with regulations, and leaves you ready to plug in and get to work — without tripping fuses or running extension leads across the lawn.
Because the best garden offices don’t just look good — they’re wired to work safely, efficiently, and for years to come.
