Bexley, London
House extension drawings in Bexley
House extension drawings in Bexley start at £695 including VAT. Bexley is a borough of family houses, with 75.3 per cent of households living in one, and it granted 94.6 per cent of the 877 householder applications it decided in its latest year.
From £695 (VAT included)
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- £2m PI insured
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- Fixed fees, VAT included
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House extension drawings in Bexley: what the design guide says
Bexley's current design guidance is the Design Guide SPD Part 2: Building Alterations and Extensions, read with the Design Guide SPD Part 1: Design Principles, and its householder rules set clear figures. For semi-detached and terraced houses, a single-storey rear extension on the boundary should not normally exceed 3.5 m deep / 3.1 m high in depth and height, with height measured to the eaves where the roof is pitched.
That is a tight boundary rule, so the position of the flank wall matters as much as the depth. The figures are written for a wall on the boundary. Where the layout allows, we test a modest step in from the fence, which gives the neighbour less wall to look at.
Upstairs the guide is more cautious. Two-storey rear extensions are normally avoided on terraced houses. On semi-detached houses they are acceptable only with no adverse effect and set in 2 m from the common boundary at first floor.
Local figures for Bexley
| Measure | Value | Period | Source |
|---|---|---|---|
| Semi-detached and terraced houses: single storey rear extensions on the boundary should not normally exceed 3.5 m in depth or 3.1 m in height (to eaves with pitched roofs). | 3.5 m deep / 3.1 m high | — | bexley.gov.uk, Bexley Design and Development Control Guidelines SPD, p.5, para 2.3.2(1) |
| Two storey rear extensions normally avoided on terraced houses; on semi-detached houses acceptable only with no adverse effects and set in 2 m from the common boundary at first floor. | 2 m | — | bexley.gov.uk, Bexley Design and Development Control Guidelines SPD, p.5-6, para 2.3.2(2) |
| New two storey side extensions on plots with at least 4 m between flank wall and boundary should be set in at least 1 m; roof should respect the original and the front be set back. | 4 m plot / 1 m set-in | — | bexley.gov.uk, Bexley Design and Development Control Guidelines SPD, p.6, para 2.3.3(2)-(3) |
| Conservation areas | 23 named conservation areas published by the council | — | planning.data.gov.uk |
| Green Belt share of the council area | 17 % of council area covered by green-belt polygons | — | planning.data.gov.uk |
| Listed building entries | 114 list entries (Historic England, within the LPA boundary) | — | planning.data.gov.uk |
| Householder decisions | 877 decisions | 1 July 2025 - 30 June 2026 | assets.publishing.service.gov.uk |
| Householder applications granted | 94.6 % | 1 July 2025 - 30 June 2026 | assets.publishing.service.gov.uk |
| Householder applications decided in time | 99.4 % decided within 8 weeks or an agreed extended period | 1 July 2025 - 30 June 2026 | assets.publishing.service.gov.uk |
| GPDO 2015 Sch 2 Pt 1 Class A, para A.1(f)(i) | 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey | — | legislation.gov.uk |
| Class A, para A.4(10)(c): development may begin if the LPA has not notified a decision within 42 days of receiving the information | 42 days | — | legislation.gov.uk |
| Householder: alterations/extensions to a single dwellinghouse, from 1 Apr 2026 | 548 GBP | — | ribblevalley.gov.uk |
A blank value means the figure has not been published, not that there are none. Check your own address with the council.
Householder applications by street in Bexley
| Street | Applications | Approved |
|---|---|---|
| Rydal Drive | 36 | 88% |
| Danson Road | 35 | 78% |
| Glenhurst Avenue | 34 | 91% |
| Westwood Lane | 34 | 94% |
| Wren Road | 33 | 89% |
| Harland Avenue | 32 | 97% |
| Halfway Street | 31 | 67% |
| Northumberland Avenue | 31 | 97% |
| Okehampton Crescent | 30 | 90% |
| Upton Road | 26 | 79% |
| Bellegrove Road | 25 | 91% |
| Latham Road | 25 | 100% |
| Mayplace Road East | 25 | 84% |
| Walton Road | 25 | 100% |
| Wansunt Road | 25 | 96% |
Single-storey rear extension: the permitted development limits
The house in section with a rear extension; the dashed lines mark the zone near the boundary.
- A · Depth beyond the original rear wall
- 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey
- B · Maximum height
- 4 m
- C · Within the zone near the boundary
- Eaves no higher than 3 m where within 2 m of the curtilage boundary
- D · Larger extension under prior approval
- 6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSI
Side extensions on wider plots
Where a house has room beside it, the guide's figures for a new two-storey side extension are 4 m plot / 1 m set-in: the space needed between the flank wall and the boundary, and the minimum set-in of the new wall. The front should also be set back to keep the original house readable.
Pitched or flat, the roof form is judged against the house, and the choice also decides how much light reaches the new room. The extension's roof should respect the original, so a matching pitch and ridge line is the safe route. We draw the street elevation with the neighbours to prove the relationship.
How Bexley has been deciding householder applications
Bexley granted 94.6 per cent of its householder applications in the latest year and decided 99.4 per cent in time. That is a high grant rate, in a borough where 68.6 per cent of households own their home.
The record is a reason to expect a straightforward process for a conventional scheme, not a promise of a result. A scheme that exceeds the boundary figures needs a clear justification on the drawings.
Green Belt and conservation areas
About 17 per cent of the council area is Green Belt, where the size of an extension is judged against the original house. Bexley also has 23 conservation areas, and Historic England lists 114 entries. We check the address for each before we quote.
If none applies, permitted development may cover a rear extension up to 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey. Larger schemes can use prior approval, which the council must decide within 42 days of receiving the information before the work may start.
What the drawings include, and the price
You receive existing and proposed plans, elevations and sections, a location plan and a block plan. Our fee starts at £695 with VAT included. The council's householder fee, £548, is paid to the council and not to us.
If the extension is on or near the boundary, the Party Wall etc. Act may apply: Adjacent excavation notice at least 1 month before work: within 3 m and deeper than the neighbour's foundations, or within 6 m and cutting a 45° line from their foundations. We tell you at quote stage whether notices are likely. The drawings help here too, because the notices must describe the work, and the sections show exactly how close the foundations come to the neighbour's wall.
Other shapes and nearby councils
Drawings are normally ready about a week after the survey, and a second chartered technologist checks each sheet before it goes to the council. If the council asks for changes, we redraw at no charge until approval. A larger family room might suit a rear extension in Bexley, while extra bedrooms point to loft conversion drawings in Bexley. The borough overview is at architectural drawings in Bexley, and the general service is on the house extension drawings hub.
The cost of the set is fixed whichever shape you choose, and a combined package with building regulations drawings is available when you are ready to build. Over the border, Dartford and Greenwich apply different local guidance.
What you receive
Related pages
Other services in Bexley
Questions
How big can a rear extension be in Bexley?
On the boundary, Bexley's design guide says single-storey extensions to semi-detached and terraced houses should not normally exceed 3.5 m deep / 3.1 m high. Set in from the boundary, the extension is judged on its effect on the neighbours.
How much do house extension drawings cost in Bexley?
From £695 including VAT, fixed before you commit. The council's application fee is paid to the council.
Can I build a two-storey extension on a terraced house in Bexley?
The guide says two-storey rear extensions are normally avoided on terraced houses. Semi-detached houses can be acceptable if set in 2 m at first floor and with no adverse effects.
Does Bexley decide applications quickly?
In the latest year 99.4 per cent of householder applications were decided within eight weeks or an agreed extension. That describes the past year and says nothing about your case.
Sources and dates
- bexley.gov.uk, retrieved
- planning.data.gov.uk, retrieved
- planning.data.gov.uk, retrieved
- planning.data.gov.uk, retrieved
- assets.publishing.service.gov.uk, retrieved
- legislation.gov.uk, retrieved
- ribblevalley.gov.uk, retrieved
- bexley.gov.uk, retrieved
- nomisweb.co.uk, retrieved
- legislation.gov.uk, retrieved
- nomisweb.co.uk, retrieved
- Contains public sector information licensed under the Open Government Licence v3.0.
- Contains OS data © Crown copyright and database right 2026.
- Contains HM Land Registry data © Crown copyright and database right 2026. This data is licensed under the Open Government Licence v3.0.
- Contains Historic England data © Historic England 2026. Contains Ordnance Survey data © Crown copyright and database right 2026.
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