DOT Wrap-around & side return extensions
When a rear extension on its own can’t give you the room you need, building round the side as well can. Done well, it turns a long, dark kitchen into one big L-shaped space. Here’s how the rules work and which houses it suits.
Planning & Building Regs rules last checked October 2026One diagram that explains the planning rules
Wrap-arounds are where homeowners most often get the Permitted Development rules wrong. Here they are on one drawing.
- Side part: single storey, no more than 4m high, and no wider than half the width of the original house.
- Rear part: 3m deep (4m for detached), or up to 6m (8m for detached) through the prior approval process.
- Wrap-around: the government’s guidance says both sets of limits apply at once. A wrap-around can be Permitted Development if it meets both.
- Conservation areas and other designated land: side extensions aren’t Permitted Development at all, so a wrap-around always needs full planning permission.
- Close to a boundary: within 2m of the boundary, the eaves can’t be higher than 3m.
- Materials: they must look similar to the existing house.
Sources: Gov.uk Permitted Development technical guidance · Planning Portal
Side return or full wrap-around?
Side return infill
Victorian and Edwardian terraces often have a narrow, under-used alley down the side of the back extension (the “outrigger”). Infilling it makes the kitchen wider without taking any garden. It’s a small footprint with a big effect, especially with a glazed roof along the party wall side to keep the middle of the house bright.
Full wrap-around
Combines a side return with a rear extension in one L-shaped build. It gives you the most extra ground-floor space of any single-storey option. It suits semis and detached houses with room down the side, and terraces where the garden allows.
Because it’s a bigger structure, expect more steelwork at the corner where the two parts meet.
The Party Wall Act: why it nearly always applies
A side return on a terrace usually means building on or right up against the boundary with next door. That brings in the Party Wall etc. Act 1996:
- work on a party wall needs at least two months’ notice
- a new wall on the boundary line needs one month’s notice
- digging foundations within 3m of next door’s building, and deeper than theirs, needs one month’s notice
It’s a process, not a permission, and most neighbours simply agree. Serve notice early, though. Otherwise, your build can be ready to start long before the notice period has run out.
We flag party wall requirements at the quote stage.
Common questions
Is a wrap-around extension Permitted Development?
It can be. The side part has to meet the side rules (single storey, no more than 4m high, no wider than half the house), and the rear part has to meet the rear depth limits. In a conservation area it always needs planning permission. We confirm this for your house before you commit.
Can I do a side return on a semi-detached house?
Yes, if there’s space at the side. On a semi, though, it’s usually just called a side extension rather than a side return. It’s still limited to half the width of the original house under Permitted Development.
Do I lose light in the middle of the house?
That’s the big risk with side returns, and the fix is a glazed roof or a run of rooflights along its length. We plan where the light comes from as part of the design.
Useful next reads
Thinking about a wrap-around or side return?
Send us a photo of the side and back of your house. We’ll tell you what’s possible under Permitted Development and what it’s likely to cost.
Wrap-around extensions near you
Based in Uttoxeter, working across Staffordshire, Derbyshire and the Midlands. Find local planning advice for your area.