Quick answer
Running electricity to a garden room typically costs £1,500-£4,000, covering the supply cable from your house, a separate consumer unit in the garden room, and internal wiring for sockets and lighting. This is one of the costs most likely to be under-quoted or quoted separately from a headline garden room price, so it’s worth clarifying explicitly with any company you’re getting quotes from. See our Garden Room Cost UK guide for how electrics fits into overall project budgeting.
What garden room electrics actually involves
The supply cable — armoured cable run from your house’s consumer unit (or a new dedicated way added to it) to the garden room, usually buried in a trench at regulation depth. The length of this run is one of the biggest cost variables, so a garden room positioned close to the house is meaningfully cheaper to wire than one at the far end of a long garden.
A separate consumer unit — the garden room gets its own small consumer unit (fuse box), allowing circuits within the room to be isolated and protected independently from the main house.
Internal wiring — sockets, lighting circuits, and any dedicated circuits for higher-draw items like heating or kitchen appliances (see our Garden Room With Kitchen Cost guide for why a kitchen changes the electrical spec).
Part P certification — electrical work in this category falls under Part P of the building regulations, meaning it should be carried out or certified by a registered, competent electrician, with appropriate notification to building control where required — see our Garden Room Building Regulations guide.
Cost by scope
Basic circuit (lighting and a few sockets) — roughly £1,500-£2,200, suitable for light use (storage, occasional-use studio) with minimal load.
Standard office/gym electrics — roughly £2,200-£3,000, covering enough sockets for computer equipment, monitors, and general appliances, plus a lighting circuit sized for regular use.
Higher-load specification (kitchen appliances, heating, or a longer cable run) — £3,000-£4,500+, reflecting a larger supply cable, more circuits, and potentially a higher-capacity consumer unit to handle appliance loads.
What affects the cost most
Distance from the house — the biggest single cost variable; a longer trench means more armoured cable and more labour, so positioning the garden room closer to your existing electrical supply meaningfully reduces cost.
Ground conditions and access — hard ground, existing paving that needs to be cut and reinstated, or difficult access for trenching equipment all add cost.
Load requirements — a garden room with just lighting and general sockets needs a much smaller supply than one running kitchen appliances, heating, or high-draw equipment (see our Garden Room Heating Guide for how heating choice affects this).
Existing house consumer unit capacity — if your main house’s consumer unit doesn’t have spare capacity for a new way, upgrading or replacing it adds to the overall cost, separate from the garden room wiring itself.
Should you use a smart/app-controlled system?
Many buyers now add smart switches, smart heating controls, or app-controlled lighting to a garden room during the initial electrical fit-out, since retrofitting this later is more disruptive and expensive than including it from the start. This is a genuinely optional upgrade rather than a necessity, but worth discussing with your electrician if it’s of interest, since the incremental cost during the initial installation is usually modest.
Do you need planning permission for garden room electrics?
No — running electricity to a garden room doesn’t trigger planning permission on its own. It does, however, fall under Part P of the building regulations regardless of whether the garden room itself is otherwise exempt from full building control approval — see our Garden Room Building Regulations guide for the general exemption thresholds and why electrics is treated differently.
Ways to manage the cost
Position the garden room to minimise cable run length — this is the single biggest lever available, and it’s a decision made at the design stage, not something that can be changed cheaply later.
Plan the full load upfront — deciding on heating, kitchen appliances, and any equipment before the electrical design is finalised avoids a costly second visit to upgrade capacity later.
Get electrics quoted separately and explicitly — since this is one of the areas most likely to be excluded from a headline garden room price, ask directly what’s included before comparing quotes between companies.
Frequently asked questions
How much does it cost to run electricity to a garden room? Typically £1,500-£4,000, depending mainly on the distance from your house and the electrical load the garden room needs to support.
Do I need a certified electrician for garden room electrics? Yes — this work falls under Part P of the building regulations and should be carried out or certified by a registered, competent electrician.
Can I run an extension lead to my garden room instead of proper wiring? This isn’t recommended for anything beyond very light, temporary use — a permanent garden room used regularly needs a proper dedicated supply and consumer unit for safety and reliability.
Does running electricity to a garden room need planning permission? No, but it does need to comply with Part P of the building regulations regardless of the garden room’s own planning or building regulations status.
*Related guides: Garden Room Cost UK · Garden Room Heating Guide · Garden Room Building Regulations · Garden Office Cost*