Harborne · B17
House Extensions in Harborne
Kingdom Build extends Victorian and Edwardian houses across Harborne (B17). Side-return infills — the classic B17 extension — is quoted per property. Parts of Harborne carry Article 4 directions that remove permitted development rights, so we check designations before designing. Free site visit, quote in 5–7 days.
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- Fixed-price contract
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House Extensions in Harborne
Kingdom Build extends Victorian and Edwardian houses across Harborne (B17). Side-return infills — the classic B17 extension — is quoted per property. Parts of Harborne carry Article 4 directions that remove permitted development rights, so we check designations before designing. Free site visit, quote in 5–7 days.
The characteristic Harborne extension is the side-return infill. The Victorian and Edwardian terraces through the village core were built with a narrow outrigger and a dead strip of side passage beside it — space that does nothing except collect bins. Roofing that strip over and knocking through gives you the wide kitchen-dining room the original plan never had, and it is comfortably the most common project we build in B17.
On the wider streets, where the stock is substantial detached and semi-detached rather than terraced, the work looks different — rear extensions with generous glazing, and occasionally a double-storey side addition. The market here is driven by families moving in for the schools and then extending rather than moving again, which tends to mean thorough projects rather than quick cosmetic ones.
The detail that shapes almost every Harborne job is what you keep. These houses usually still have their original encaustic tiled hallway floors, cornicing, fireplaces and sash windows, and those are worth substantially more retained than replaced. We plan the structural work around them — protecting a tiled floor properly during a knock-through is a nuisance and considerably cheaper than sourcing a replacement afterwards.
Costs
How much does house extension cost in Harborne?
What you pay depends mostly on which of the options below your property allows — the gap between the simplest and the most involved is substantial, and it is decided by the building rather than by us. We survey first, then give you a single fixed price. We would rather do that than publish a range that does not survive contact with your Harborne property.
| Option |
|---|
| Side-return infillThe classic Harborne extension. Structurally involved — needs a steel frame where the original side wall comes out. |
| Single-storey rear extension20–30m² on a Victorian or Edwardian property, including period-appropriate detailing. |
| Wraparound extensionSide return plus rear in one contract — the best value per m² because groundworks and roof happen once. |
| Double-storey extensionMore common on the detached stock. Always a full planning application. |
Free site visit across B17, then a written fixed-price quote within 5–7 days. Get yours.
Planning
Do you need planning permission in Harborne?
Your planning authority is Birmingham City Council. Here is what that means in practice for house extensions in B17.
- Parts of Harborne are covered by Article 4 directions, which remove permitted development rights that apply elsewhere. This is the single most important thing to establish before you spend anything on drawings — we check the exact designation on your address at the survey stage.
- The conservation area covers the High Street and several of the older residential streets, removing permitted development rights and adding control over materials, windows and roof form.
- Outside the Article 4 and conservation boundaries, standard permitted development applies — 3m rear on a semi or terrace, 6m via Larger Home Extension prior approval.
- Side-return infills on terraces almost always trigger the Party Wall Act on both sides, since you are building along one boundary and excavating near the other.
- Birmingham City Council expects new brickwork on Victorian stock to be matched properly. Harborne's red brick with lime mortar is not the same as inter-war brick and needs sourcing rather than approximating.
Local property
What the Harborne housing stock means for your extension
- Victorian terraces (village core, B17): side-return infill is the standard project, usually combined with a rear extension into a wraparound.
- Edwardian semis: wider frontages and often a deeper garden, so rear extensions with wide glazing spans work well.
- Substantial detached (wider streets): double-storey side additions and large rear extensions, frequently with a full ground-floor replan.
- Solid brick walls with lime mortar on the older stock — new work needs to be built in lime, not cement, so the wall can still breathe.
- Original features worth retaining: encaustic tiled hallways, cornicing, ceiling roses, fireplaces and sash windows. Protecting them during the build is part of our scope.
Our work
House Extensions we have delivered
House Extensions in Harborne — your questions
Other work we do in Harborne
House Extensions in nearby areas
- House Extensions in Sutton Coldfield
- House Extensions in Solihull
- House Extensions in Edgbaston
- House Extensions in Walsall
- House Extensions in Lichfield
Or read the general house extensions guide covering the whole West Midlands.
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Get a free quote for your Harborne project
Free site visit across B17. Fixed-price quote in 5–7 days. No obligation.