Extension leads running permanently between rooms, a shed or garden annexe with no power supply at all, or a workshop that trips the whole house every time the compressor kicks in. None of these are meant to be permanent solutions, and each one is a sign the existing circuit simply isn’t set up for what you’re actually using it for.
Why this comes up
A shed, garage, or garden annexe that’s never had its own power supply.
A workshop or home office drawing more load than the existing circuit can comfortably handle.
Extension leads running permanently between rooms as an unofficial fix.
Wanting a dedicated circuit for something specific, like a workshop or a home EV charger.
A home office setup drawing more continuous load than a general power circuit was designed for.
Wanting power to a pool, pump shed, or outdoor kitchen area.
How we handle it
Check the existing supply and consumer unit can take the additional load.
Agree the route and whether a sub-board is the better answer for the property.
Discuss whether a sub-board on site makes more sense than running every new circuit back to the main board.
Install, test, and update the board schedule to reflect the new circuit.
Certify the new circuits before handing back over to you.
What to expect
Single circuits inside the house are usually a day’s work. Runs to a detached shed or garden annexe depend heavily on distance and whether trenching is needed for underground cable. For a detached structure like a shed or garden annexe, we’ll also confirm whether a local sub-board is the better long-term answer rather than several individual circuits run separately.
What it costs
Driven by cable run length and access more than by the circuit itself. A short run to an existing wall cavity is far cheaper than trenching across a garden. Trenching cost varies a lot by ground type and distance, so we’ll always walk the actual route with you before finalising the quote.
Common questions
Can I run a lead to the shed instead?
Not as a permanent arrangement. It’s unsafe outdoors long-term and won’t pass an inspection.
Do I need a sub-board for a garden annexe?
Usually, yes, particularly if it has its own kitchen or bathroom. We’ll confirm based on what’s actually being installed out there.
How deep does outdoor cable need to be buried?
Depends on the cable type and whether it’s mechanically protected, we’ll follow the correct depth and method for your situation.
Can you add a circuit without opening up walls?
Sometimes, depending on roof and subfloor access. We’ll assess the property before quoting rather than assuming.
Will this trip my existing RCD less?
Yes, that’s often the point. Splitting a workshop or high-draw area onto its own circuit stops it dragging down everything else in the house.
Do I need planning permission to run power to a shed?
Generally no for standard domestic power, though we’ll flag it if your specific job needs anything beyond normal electrical work.
Can you supply power to a pool or spa?
Yes, with the correct isolation and RCD requirements that apply specifically to pools and spas, which are stricter than a standard circuit.