Do You Need Planning Permission for a Garden Room?

For most homeowners in the UK, the answer is no. The majority of garden rooms are built under permitted development rights, which means you can add one to your property without applying for full planning permission — provided you stay within a set of clear rules.

Permitted development: the basic rules

Your garden room is likely to fall under permitted development if it meets these conditions:

• It’s single-storey, with an eaves height no higher than 2.5m and an overall height no higher than 4m with a dual-pitched roof, or 3m with any other roof (including flat roofs)
• If it’s within 2m of a boundary, its overall height is no more than 2.5m
• It covers no more than 50% of the total area of land around your original house
• It sits behind the principal elevation of the house (not in front, facing the road)
• It isn’t used as separate, independent living accommodation (self-contained sleeping and cooking facilities)

When you might need permission

A small number of situations take a garden room outside permitted development, including:

• Listed buildings — any structure in the grounds of a listed building typically needs consent
• Conservation areas and Areas of Outstanding Natural Beauty, where size limits are stricter
• Properties where permitted development rights have been removed by a previous planning condition
• Flats and maisonettes, which don’t automatically have permitted development rights

What we do to protect you

During your site survey, we check your specific plot against local planning constraints before your design is finalised. If your project does need an application, we’ll tell you clearly and help you understand what’s involved — you won’t find out halfway through the process.

Want the exact figures for your project? See our Price Guide or get in touch to arrange a free site survey.