6×3m Garden Room
Serious Space for Serious Builds
Overview
The 6×3m is the go-to size for those who want a proper room at the bottom of their garden. Long and lean, it suits workshops, studios, and dual-function spaces.
What it's great for
Furniture & layout
The extra length allows for dedicated zones — a working area at one end and a relaxation or meeting area at the other. Perfect for photographers needing a shooting area and editing desk.
Planning permission
At 18m², building regulations become more likely to apply, particularly for electrical work and structural elements. Check with your local authority.
Build timeline
5–6 weekends. The longer walls need more care with straightness and bracing.
Key materials
- ✓~90 linear metres of 4×2 CLS timber
- ✓18m² of EPDM roofing membrane
- ✓20 sheets of 18mm OSB
- ✓18m² of PIR insulation
- ✓36 linear metres of cladding
For exact quantities and a full materials list, see the Build Pack.
Estimated DIY cost
Standard spec, with electrics — materials only
Your DIY Cost Estimate
Materials only — does not include your time
Professional cost is an estimate based on typical UK contractor rates (approx. 2.75× materials). Actual quotes will vary.
Try the full calculator to adjust spec and extras.
Free build checklist
Get our material checklist and build timeline free.
Other size guides
Ready to build your garden room?
Get the complete DIY build pack — full plans, materials list, and step-by-step guides for £49.