House Extensions Bexleyheath

GS Renovation builds house extensions throughout Bexleyheath, making the most of the generous plots that came with its 1930s semi-detached and interwar homes. We handle groundworks, steelwork, roofing and a full fit-out, guiding you through Bexley Council permissions from the first sketch.

In Bexleyheath, a single-storey rear extension typically starts from £40,000, or £2,000 to £2,800 per m² (indicative London ranges, Architecture for London, Resi, MyBuilder and Checkatrade, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Bexleyheath: the structural engineer we appoint designs the structure, we build it, and building control signs it off.

Side return and kitchen extensions in Bexleyheath

Interwar Bexleyheath houses were built on wider plots than inner-London terraces, so there is often real room to extend. On a Bexleyheath semi, a side return extension usually means building over the side passage beside the kitchen: it keeps the garden, widens a narrow kitchen, and joined to a single-storey rear extension it becomes a wrap-around kitchen-diner. A side extension has to stay within the permitted development limits on height and width, needs planning permission in a conservation area, and on a corner plot facing a road needs planning too. We dig and pour the foundations, install the steel beams and tie the new roof neatly into the existing 1930s roofline.

Whether your extension is permitted development or needs a full planning application to Bexley Council depends on your specific property, its size and whether it has been extended before. We assess this at the outset so you know exactly which route applies before any work begins in DA6.

Housing in Bexleyheath

Of the 8,550 homes the valuation list records in Bexleyheath, 19% were built before 1919, 40% between the wars and 41% since 1945; 27% are flats and 73% are houses. A rear extension on a semi in Bexleyheath digs beside the attached neighbour, so one party wall notice is usual, and 41% of homes here are semi-detached.

Extending a Bexleyheath semi under the new Bexley design limits

Bexley adopted the Design Guide SPD Part 2, which includes Building Alterations and Extensions guidance, on 29 June 2026. For a Bexleyheath semi that needs planning permission rather than relying on permitted development, the working numbers are these. An extension to a terraced or semi-detached dwelling should typically not exceed 3.5m deep. A single-storey extension should not exceed 4m at its highest point, with an eaves height of no more than 3m. Draw the extension to those limits from the first sketch. A scheme drawn deeper and cut back after comments costs a second set of drawings and a second round of engineer's calculations.

In the Red House Lane Conservation Area the guidance is narrower still. The Red House Lane appraisal says further development might be permissible where proposals use current enclosed areas at ground floor level to the rear. So for a house there that needs planning permission, rebuilding or enclosing what already exists at the back is the realistic starting point, not a new projection into the garden. Side extensions and two-storey rear extensions are not permitted development in a conservation area, so on Red House Lane they always need an application. Check whether your address is inside the boundary before commissioning drawings.

Double-storey extensions on Bexleyheath plots

The width of many Bexleyheath interwar plots also suits a double-storey side extension, with planning permission from Bexley Council, adding a downstairs room and an extra bedroom above without eating into the garden. Digging close to the neighbour brings the Party Wall Act into play, so you serve the correct notices on the adjoining owner as building owner, with the drawings we supply, and agree the works before we break ground.

We manage the whole build: foundations and groundworks, load-bearing steelwork, the new roof, windows to match the interwar character, and the full internal fit-out with plastering, electrics and heating. Building regulations govern the structure and insulation, and we book Bexley Council building control inspections at each key stage through to completion.

• Steel goalpost frames where the rear wall opens up
• Full fit-out, finishing and making good
• Roof works and structural alterations at roof level

VOA Council Tax stock of properties, March 2025, for Bexleyheath Broadway and Danson Park. Counts rounded by the VOA.

Two or three things usually come up alongside house extensions on a Bexleyheath job: RSJ and steel beam installation in Bexleyheath, house extensions across Bexley, side return infills, a garage conversion instead, how we handle house extensions across London and Basement Conversion Cost.

Why Choose GS Renovation in Bexleyheath

Homeowners across Bexleyheath choose GS Renovation because we run the extension from design to decoration as one project. We know how interwar semis are built, we handle planning versus permitted development and building control, and our founder's 30+ years on the tools means fewer surprises on your DA6 site.

• Programme planned around party wall notice periods before excavation near a neighbour
• Foundation depth set after trial holes, drains and trees are checked
• Honest updates if a date or a detail has to move

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Structural design is by the consulting engineer appointed to your project.