How Much Does a Garden Room Cost in the UK?
A purpose-built garden room — also called a garden studio, garden office, or garden lodge — is an insulated, year-round structure separate from the main house. Unlike a standard garden shed, a proper garden room is built to building-grade insulation standards and can be used as a home office, gym, studio, or extra bedroom. Costs depend heavily on size, specification, and whether mains services are connected.
Typical Cost (UK, 2026)
All costs are indicative estimates. Obtain at least 3 quotes from qualified builders. Prices exclude VAT (20%).
Factors Affecting the Cost
Size
A compact 10m² garden office costs from around £8,000; a large 30m² garden room with en-suite can exceed £35,000.
Insulation level
Full building-regulations-standard insulation (required for a habitable room) costs more than a basic "use in summer" specification.
Glazing
Full-width bifold or sliding doors significantly increase cost. A simple French door with one side window is far cheaper.
Electrics and heating
Mains electricity connection adds £1,000–£3,000. Underfloor heating, air conditioning, or a dedicated consumer unit adds further cost.
Plumbing
Adding a kitchenette or shower room adds significant cost — typically £3,000–£8,000.
External finish
Treated timber cladding is standard. Cedar, composite, or painted render finishes cost more.
Cost Breakdown
| Item | Basic | Mid-range | High-end |
|---|---|---|---|
| Base (concrete slab or raised deck) | £800 | £1,500 | £3,500 |
| Structure (frame, walls) | £3,000 | £6,000 | £12,000 |
| External cladding | £800 | £2,000 | £5,000 |
| Roofing | £1,000 | £2,500 | £5,000 |
| Glazing (windows and doors) | £1,500 | £3,500 | £8,000 |
| Insulation | £500 | £1,200 | £2,500 |
| Electrics | £1,000 | £2,000 | £4,000 |
| Interior fit-out (flooring, walls, ceiling) | £1,500 | £3,500 | £8,000 |
Costs are indicative and exclude VAT. Regional variations apply.
Typical Timeline
2–6 weeks from installation start
Frequently Asked Questions
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