House Extensions · SE9 Eltham
Greenwich controls the historic Progress Estate and the Eltham Palace setting; SE9 is a settled, affordable inter-war family market.
Working across the whole borough rather than just this area? See house extensions in Greenwich.
House extensions in Eltham are dominated by single-storey rear and side-return additions on SE9's inter-war semis and detached houses across eltham, with double-storey and wrap-around schemes where the plot allows. Greenwich Council weighs depth, height and neighbour daylight; many extensions across Eltham, Mottingham, Eltham Park, New Eltham fringe are Permitted Development, which we confirm with a Lawful Development Certificate before you build.
The whole spectrum — rear extensions, side returns, wraparounds, double-storey, basement digs. Planning-led design with detailed technical phase, ideal for inter-war semis and detached houses across eltham typical of Eltham.
Across Eltham, Mottingham, Eltham Park, New Eltham fringe in SE9, the dominant property is inter-war semis and detached houses across eltham and mottingham, with the historic core around eltham palace and pockets of post-war estate. That stock shapes what house extension drawings looks like here: the right approach for a period terrace differs from a mansion-block flat or a new-build, and Greenwich Council judges each on design quality and neighbour impact. We survey the specific Eltham property, confirm the planning route — Permitted Development, a Lawful Development Certificate, or full planning — and draw a council-ready set tailored to the SE9 streetscape.
Housing stock in SE9: Inter-war semis and detached houses across Eltham and Mottingham, with the historic core around Eltham Palace and pockets of post-war estate.
Within the district: Eltham, Mottingham, Eltham Park, New Eltham fringe.
Streets we know in SE9: the Eltham Park and Progress Estate roads, Court Road, Glenesk Road and the Well Hall streets. Each road has its own building line, boundary treatment and precedent that Greenwich Council weighs when assessing a house extension drawings scheme.
Conservation areas: Progress Estate (Well Hall), Eltham Palace, Eltham High Street. Inside these, most external work needs full planning and a Heritage Statement.
Getting around SE9: Eltham, Mottingham and New Eltham rail to London Bridge, Cannon Street and Victoria.
Property values: SE9 property had a 2025 median of £473,240, while the borough's 882 terraced sales returned a median of £495,000 — both figures published by HM Land Registry from completed transactions.
Borough character: World Heritage Site status in Greenwich town centre adds heritage weight; outer borough areas (Eltham, Thamesmead) generally permissive.
Measured existing survey, photographic record, Article 4 and conservation check specific to Eltham before we quote.
2–3 design options at concept stage — alternative layouts, glazing, roof forms.
Site location plan, existing and proposed plans, elevations, sections, D&AS where required.
Part L thermal, Part B fire, Part M accessibility, structural strategy.
Steel beam, foundation, lintel design. Chartered engineer sign-off.
Party Wall notices where needed; Thames Water Build Over Agreement where within 3m of a public sewer.
Single planning or building-regs submission.
Planning + building regs + structural.
Listed, conservation or complex sites.
Yes. The inter-war semis and detached houses around Court Road and Glenesk Road suit rear, side and loft extensions, much of it within Permitted Development outside the conservation areas, confirmed with a Lawful Development Certificate. We confirm the route and draw to Greenwich's checklist.
The Progress Estate is a celebrated First World War garden-suburb conservation area with strong, uniform arts-and-crafts character, so external changes there are tightly assessed on materials, render and roofs. We design sympathetically and submit a full application with a Heritage Statement where the designation applies.
Usually yes on the inter-war semis — a hip-to-gable plus rear dormer within the volume allowance, confirmed by a Lawful Development Certificate, provided you're not in the Progress Estate or another conservation area. We check the constraints for your road and draw it for Building Control.
Greenwich's terraced median for 2025 was £495,000 from 882 sales and its semi-detached median £597,500 — a closer guide to Eltham houses than the £473,240 all-property district figure.
Greenwich Council charges its own statutory application fee (currently £548 for a householder planning application, £610 for a full application). We quote the drawings as one fixed price and the free site survey covers every SE9 address.
For a SE9 project across Eltham, Mottingham, Eltham Park, New Eltham fringe, expect roughly 3–4 weeks from instruction to submission: week 1 the measured survey, weeks 2–3 the drawings and your revisions, then validation and the statutory determination by Greenwich Council (8 weeks for a householder application). We carry the Eltham application through every officer query to the decision.
Eltham (SE9) sits primarily in Greenwich, so applications are decided by Greenwich Council. Conservation areas within SE9 include Progress Estate (Well Hall), Eltham Palace, Eltham High Street, where full planning and a Heritage Statement are required. We confirm the planning route for your exact address before quoting.
Almost always. Any structural work behind house extension drawings in Eltham — new openings, steel beams, loft floors, foundations — needs Building Regulations approval covering structure (Part A), fire escape (Part B) and insulation (Part L), submitted to Greenwich Council Building Control or an approved inspector. On SE9's typically terraced and semi-detached stock, a Party Wall notice to adjoining neighbours is normally required before the steelwork. We coordinate both as part of the Complete package.
In value terms, yes. The bigger risk is an unapproved or non-compliant scheme — which is why council-ready drawings and a clean Building Control sign-off matter on SE9 homes.
Moving, or weighing up a site in the next borough along? Here is the complete service list for SE3 and SE10.
Pick a slot that suits you. No obligation and no sales pressure, just straight answers on your planning route.
Every SE9 postcode district we draw in, the stock that dominates it and the authority that validates a house extension there. SE9 fees below are the statutory England rates for 2026, not house extension estimates.
| Postcode | Area | Dominant stock | What it means for a house extension |
|---|---|---|---|
| SE9 | Eltham / Mottingham | 1930s semi-detached, post-war flats | Eltham / Mottingham is split at SE9. Either Greenwich Council or Bromley Council can determine a house extension here, so the SE9 address is checked against both policies maps first. |
| SE9 | Eltham | 1930s semi-detached, post-war flats | Eltham sits inside SE9; house extension proposals here are determined by Greenwich Council. |
| SE9 | New Eltham | 1930s semi-detached | New Eltham sits inside SE9; house extension proposals here are determined by Greenwich Council. |
| SE2 | Abbey Wood | mixed stock | Adjoining district to SE9, also inside Greenwich for house extension purposes. |
| SE3 | Blackheath / Kidbrooke | Georgian villas, Victorian terraces | Adjoining district to SE9, also inside Greenwich for house extension purposes. |
| SE7 | Charlton | Victorian villas, 1930s semi-detached | Adjoining district to SE9, also inside Greenwich for house extension purposes. |
| SE20 | Anerley / Penge | Victorian and Edwardian terraces | Adjoining district to SE9, also inside Bromley for house extension purposes. |
| BR1 | Bromley / Bickley | Victorian terraces, Edwardian villas, post-war flats | Adjoining district to SE9, also inside Bromley for house extension purposes. |
| BR2 | Hayes / Keston | Victorian terraces, Edwardian villas, post-war flats | Adjoining district to SE9, also inside Bromley for house extension purposes. |
| BR3 | Beckenham | Edwardian villas, 1930s semi-detached | Adjoining district to SE9, also inside Bromley for house extension purposes. |
Roof pitch, wall build-up and plot depth change every few SE9 streets, and each one changes what a house extension can achieve at that address.
SE9 (Eltham / Mottingham) conservation designations: there are 20 across Greenwich Council, Eltham Park, Greenwich Town Centre (World Heritage Site), Blackheath among them. Designation costs a SE9 (Eltham / Mottingham) owner the permitted-development route: a house extension then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Blackheath is the SE9 (Eltham / Mottingham) designation that most often changes a house extension design.
Article 4 and your SE9 (Eltham / Mottingham) house extension: Greenwich Council has made no borough-wide direction, so permitted development for a house extension in SE9 (Eltham / Mottingham) generally survives outside SE9 (Eltham / Mottingham) conservation areas and listed curtilages. A Lawful Development Certificate at £274 is how a SE9 owner records that a house extension was lawful.
SE9 (Eltham / Mottingham) housing stock: Georgian in Greenwich town centre; Victorian terraces in East Greenwich, Charlton; inter-war semi-detached in Eltham; new-build along the riverside. World Heritage Site status in Greenwich town centre adds heritage weight; outer borough areas (Eltham, Thamesmead) generally permissive. Read that before choosing a house extension route in SE9 (Eltham / Mottingham) — construction, not postcode, sets what is achievable. Greenwich Council charges £548 for a householder application and has 8 weeks to determine it.
SE9 (Eltham / Mottingham) conservation designations: there are 48 across Bromley Council, Bromley Town, Chislehurst, Beckenham among them. Designation costs a SE9 (Eltham / Mottingham) owner the permitted-development route: a house extension then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Chislehurst is the SE9 (Eltham / Mottingham) designation that most often changes a house extension design.
Article 4 and your SE9 (Eltham / Mottingham) house extension: Bromley Council has made no borough-wide direction, so permitted development for a house extension in SE9 (Eltham / Mottingham) generally survives outside SE9 (Eltham / Mottingham) conservation areas and listed curtilages. A Lawful Development Certificate at £274 is how a SE9 owner records that a house extension was lawful.
SE9 (Eltham / Mottingham) housing stock: Large 1930s detached and semi-detached in Chislehurst and Bickley; Edwardian in Beckenham; Victorian in Bromley town; Metropolitan Green Belt covers significant rural-fringe land. Largest London borough by area; substantial Green Belt; conservation areas in most town centres; generally permissive elsewhere. Read that before choosing a house extension route in SE9 (Eltham / Mottingham) — construction, not postcode, sets what is achievable. Bromley Council charges £548 for a householder application and has 8 weeks to determine it.
Sources for this SE9 house extension page: borough policies maps and conservation-area registers (2025–26), Royal Mail postcode district boundaries, the Town and Country Planning (Fees for Applications) (England) Regulations, the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended, and the Party Wall etc. Act 1996.
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