The UK has four separate planning systems — England, Scotland, Wales and Northern Ireland each set their own rules for what can be built without planning permission. Even within England, a freestanding framed building (a carport or garden building) is treated differently from one attached to your house. This page explains the general picture for England, where the detailed rules are best documented, and points you to where to check for Scotland, Wales and Northern Ireland.
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Delivery price on requestFramed Buildings · Planning Permission & Regulations
Unlike the Netherlands' single national framework, the UK has four separate planning systems — England, Scotland, Wales and Northern Ireland each set their own rules for what can be built without planning permission. Even within England, a freestanding framed building (a carport or garden building) is treated differently from one attached to your house. This page explains the general picture for England, where the detailed rules are best documented, and points you to where to check for Scotland, Wales and Northern Ireland.
Accuracy note: The figures below reflect publicly available planning guidance for England as it stood in 2026. Permitted development rules are updated periodically and can also be removed for individual properties (Article 4 directions, listed buildings, conservation areas) — always confirm current rules with your local planning authority before ordering.
Planning is a devolved matter in the UK: England, Scotland, Wales and Northern Ireland each operate their own permitted development system under separate legislation. A framed building that's permitted development in England is not automatically permitted development in Scotland or Wales — the tests and thresholds differ. The detail below applies specifically to England.
A freestanding framed building is normally assessed as an "outbuilding" under Schedule 2, Part 1, Class E of England's General Permitted Development Order. It's usually permitted development, without a planning application, if all of the following apply:
No part is on land forward of the principal elevation (the main front wall) of the original house.
Single storey, with eaves no higher than 2.5m.
No higher than 4m with a dual-pitched roof, or 3m with any other roof type.
If any part is within 2m of the curtilage boundary, maximum overall height drops to 2.5m.
Together with other outbuildings, it covers no more than 50% of the curtilage (the land around the original house).
It's within the curtilage of the house and used for a purpose incidental to the home, such as sheltering a vehicle.
This is the detail that catches people out most often: a framed building physically fixed to the house — a roof supported on the house wall with posts, even from a kit sold as "freestanding" — is normally treated as an extension under Class A, not as an outbuilding under Class E. Class A has separate, generally stricter tests for position, height, width and projection, and front, side and rear positions are all assessed differently. A side lean-to set back from the front wall may still be permitted development; a structure projecting in front of the house typically will not be.
Planning permission and Building Regulations are assessed independently. A detached framed building of 30m² or less is generally exempt from Building Regulations if it's at least 1m from a boundary, built from substantially non-combustible materials, or open on at least two sides — confirm the exact position with your local building control body. Structures over 30m² generally do require a Building Regulations application, and any electrical work (an EV charger, for example) falls under Part P and must be carried out or certified by a qualified electrician.
The figures above apply to England only. Scotland, Wales and Northern Ireland each operate their own permitted development regime, under their own legislation, with different size, height and position tests. If your property is in one of these nations, check directly with your local council or the relevant national planning portal rather than applying the English figures.
Permitted development rights can be restricted or removed entirely for listed buildings, properties in conservation areas or Areas of Outstanding Natural Beauty, and homes subject to an Article 4 direction. In these cases, a full planning application — or listed building consent — is usually required regardless of size. Check your title deeds or your local planning register if you're unsure.
Not sure whether your ideal framed building fits within permitted development? We have plenty of experience with common dimensions and can advise on a design that suits your situation. Final responsibility for checking and, where necessary, applying for planning permission remains with you as the property owner.
No. In England, a detached framed building often qualifies as permitted development if it meets the outbuilding tests (position, height, footprint). Scotland, Wales and Northern Ireland have their own separate rules.
Generally 4m with a dual-pitched roof or 3m with any other roof type, dropping to 2.5m if any part is within 2m of a boundary, with eaves no higher than 2.5m.
Yes. A structure fixed to the house is normally assessed as an extension (Class A) rather than an outbuilding (Class E), with different and generally stricter tests for position and size.
Contact your local council or the relevant national planning portal, since each nation operates its own permitted development system with different thresholds.