The semi-detached house and its side wall
When the council last surveyed households, in 2017, a third of occupied homes in Leeds were semis or town houses. That makes the side of a semi the place where a lot of Leeds families look first for more room, and it's where the council's Householder Design Guide is at its firmest.
On a street of regular semis, a two storey side addition should keep at least a 1.0m gap to the side boundary and step back 2.0m from the front wall. The guide is blunt about the result. Normally only one small bedroom can be created, and a side extension with no gap to the boundary will not normally be acceptable. The point is to stop pairs of semis joining up into a continuous terrace.
Width is capped at around two thirds of the main house, single or two storey, and the roof should copy the pitch, shape and materials of the original. Plan around the gap from day one.
End terraces get a little more room. The guide says a well designed two storey side addition may be possible there.
Which type of extension suits which Leeds house
Single storey rear. Permitted development allows 3 metres off the back of a semi or terrace and 4 on a detached house, with 6 and 8 possible through prior approval. If you need a planning application instead, Leeds normally accepts 3.0m on a shared boundary, less where gardens are short.
Kitchen. Usually a single storey off the back of a terrace or semi. Keep at least half the garden, which the council expects as a rule of thumb.
Two storey. Hard on a semi or terrace. At first floor on a shared boundary Leeds wants no more than 1.0m beyond the neighbour's back wall, though 3.0m can work if the upper part is held 2.0m off both boundaries.
Wrap-around. Single storey L shapes suit semis with a driveway at the side. Kept to one storey and within half the house's width, the side leg can be permitted development outside a conservation area.
Side return. Fits a through terrace with a back outrigger and a strip of yard beside it. A back-to-back has no rear wall of its own, so this one doesn't apply there.
Open plan. Opening the old back wall of a gritstone or red brick house means a steel and padstones carrying old masonry. Get the engineer in before the builder prices it.
Downstairs bedroom. Often the better answer on a bungalow, and the 2017 survey counted around one home in sixteen as one. Keep the shower room level with the bedroom.
Home office. An attached study needs less garden than a cabin at the bottom, which matters on a short terrace plot. Put a conservatory-style one at the back, as Leeds dislikes them where they can be seen from the street.
Planning. Search the council's Public Access register for your street, and read the design guide. Its diagrams show the tests officers apply.
Cost. No Leeds price here. Matching stone, steelwork and what turns up in the footings move the figure more than floor area, so compare three itemised quotes.
Windows, distances and the 45 degree line
Leeds measures neighbour impact with a few codes. The 45 degree line runs from the nearest edge of a neighbour's main window and mostly governs two storey work, though officers can apply it to single storey schemes too. Between main windows facing each other at ground floor, the guide looks for 21.0m. Between a main window and a secondary one, 18.0m. A blank side wall should be 12 metres from a main window opposite.
These are a guide, not a hard and fast rule, in the council's words. Still, a back extension on a short garden that breaks two of them will struggle. Side windows upstairs should be obscure glazed unless they serve a bathroom or landing.
Two storey additions on the front are not normally acceptable. Large porches with seating areas tend to be refused as well. On a corner plot, the design has to work from both streets.
Conservation areas, coal, becks and Green Belt
Leeds has 80 conservation areas, and the council says small extensions inside them need permission. National rules also take away side extensions, two storey rear additions and cladding there, and the prior approval route for a 6 metre rear doesn't apply. New work should normally use traditional local materials.
Underground, the British Geological Survey records coal worked from bell pits up to 10 metres deep, many never mapped, with pillar and stall workings found 3 metres down at Richmond Hill. Look up your address on the Mining Remediation Authority map before digging footings. In a development high risk area, work that could reach old seams or a mine entry needs its permit.
Flood schemes now cover the Aire, the Wharfe at Otley and Wyke Beck, but defences don't change the flood zone. An extension in Flood Zone 2 or 3 still needs a flood risk assessment. The council has also noted that paved front gardens drive most of the growth in hard surfaces across Leeds, so think about drainage.
Out in the Green Belt villages, policy HDG3 uses about a thirty percent volume increase over the original house as its guideline, and earlier additions count against it.
Where these facts come from
- Leeds City Council: Householder Design Guide SPD (2012)
- Leeds City Council: conservation areas
- GOV.UK: permitted development rights for householders, technical guidance
- Leeds Strategic Housing Market Assessment 2017
- British Geological Survey: Leeds Sheet 70 memoir
- Mining Remediation Authority: home extensions in former coal mining areas
- Leeds Local Plan Update: Flood Risk Background Paper (2022)
- Environment Agency: flood risk assessment standing advice
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Questions people in Leeds ask
I've got a 1930s semi in Leeds. Can I go two storeys at the side and get two bedrooms?
Usually not. With a 1.0m gap to the boundary and a 2.0m step back from the front, the guide says normally only one small bedroom fits. A bigger plot or a detached neighbour can change that, so ask the council for pre-application advice.
Can I build out the front of a back-to-back in Harehills or Beeston?
Anything in front of the main elevation falls outside permitted development, so it needs an application. Leeds normally refuses two storey front extensions. A small porch in matching materials stands a much better chance.
We live in a village near Wetherby that's in the Green Belt. How much can we add?
The council works to a guideline of about thirty percent more volume than the original house. Past extensions, including ones built by earlier owners, come off that allowance.
Our house backs onto the Wharfe at Otley. Does the flood scheme mean we can skip the flood assessment?
No. If the house is in Flood Zone 2 or 3 on the Environment Agency map, a planning application for an extension needs a flood risk assessment, and the standing advice for minor extensions tells you what to include.