The Rules, Plainly

Garden room planning permission, explained

Garden room planning permission, in plain English: you usually don't need it — most garden rooms fall within permitted development. And when you do, we handle the whole thing.

Book a Scoping Call Download Brochure

The Headline Question

Do you need planning permission for a garden room?

Usually, no. Most garden rooms are covered by permitted development rights, which let you build garden structures without a planning application — provided you stay inside the size, height and siting rules below. You will need permission for sleeping accommodation, for commercial use, in conservation areas, and on listed properties.

The Size Rules

What size garden room without planning permission?

Rule	Permitted development limit
Height (within 2m of a boundary)	2.5m maximum overall
Height (elsewhere)	4m dual-pitched roof; 3m otherwise
Garden coverage	Outbuildings may cover no more than 50% of the land around the house
Position	Not forward of the principal elevation
Use	Incidental to the house — offices, gyms and hobby rooms qualify; bedrooms do not

England, general case. Wales, Scotland and NI differ in detail; designated land tightens everything. We confirm your position at scoping.

When You Do

When you DO need permission

Annexes

Sleeping accommodation means ancillary residential use — a planning application, which we manage. Annexe guide →

Commercial use

Paying guests change the use class. Standard territory for us. Commercial →

Protected settings

Listed buildings, conservation areas and AONBs need consent — where an underground build is often the most approvable option there is.

Our Home Ground

Underground buildings and planning

Can you build an underground room in your garden in the UK? Yes. Height limits are the binding constraint in most garden applications — and an earth-sheltered building barely has any. Grassed over, it has next to no visual impact, which is precisely what planning committees are asked to protect. It is why our approval record includes settings where a conventional outbuilding would have been refused on sight.

The Offer

We handle planning for you

Drawings, applications, submissions and the council conversation are part of every turnkey build — a managed 12-week window inside the four-step process. You never fill in a planning form.

FAQ

Planning questions, answered

Do underground rooms count against permitted development height limits?

Height is measured above ground level, which is exactly where an earth-sheltered building keeps its profile lowest — one of its biggest planning advantages.

How long does planning permission take?

A standard householder application runs about 8–12 weeks. We build a 12-week window into the project timeline and manage all of it.

What if my application is refused?

Rare on our builds because we pre-check the site position before applying — that is part of what scoping is for. Where risk exists we tell you before the deposit, not after.

Stop reading forums. Ask us.

Download the brochure for the full planning section — or book a scoping call and get your site's answer in thirty minutes.

Download the Brochure Book a Scoping Call