House Extensions · SW14 Mortlake
Fixed-fee house extension drawings for Mortlake, East Sheen, Sheen, North Sheen fringe in the SW14 postcode, drawn by an MCIAT-chartered architectural technologist and submitted to Richmond Council. Richmond controls the Mortlake and East Sheen conservation areas; the former Stag Brewery is a major local redevelopment.
MCIAT chartered drawings for planning, building regs, lofts and extensions — fixed fees 30% below typical London architects. Tell us what you need and we’ll reply the same working day.
House extensions in Mortlake are dominated by single-storey rear and side-return additions on SW14's edwardian and inter-war terraces and semis around, with double-storey and wrap-around schemes where the plot allows. Richmond Council weighs depth, height and neighbour daylight; many extensions across Mortlake, East Sheen, Sheen, North Sheen 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 edwardian and inter-war terraces and semis around typical of Mortlake.
Across Mortlake, East Sheen, Sheen, North Sheen fringe in SW14, the dominant property is edwardian and inter-war terraces and semis around mortlake and east sheen, with larger houses toward richmond park. 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 Richmond Council judges each on design quality and neighbour impact. We survey the specific Mortlake property, confirm the planning route — Permitted Development, a Lawful Development Certificate, or full planning — and draw a council-ready set tailored to the SW14 streetscape.
Housing stock in SW14: Edwardian and inter-war terraces and semis around Mortlake and East Sheen, with larger houses toward Richmond Park.
Within the district: Mortlake, East Sheen, Sheen, North Sheen fringe.
Streets we know in SW14: the East Sheen streets (Christchurch Road, Sheen Lane), the Mortlake riverside and the Palewell streets. Each road has its own building line, boundary treatment and precedent that Richmond Council weighs when assessing a house extension drawings scheme.
Conservation areas: Mortlake / The Green, East Sheen, Sheen Common. Inside these, most external work needs full planning and a Heritage Statement.
Getting around SW14: Mortlake and North Sheen rail to Waterloo, plus Richmond nearby for the District line.
Regeneration: Mortlake falls within or beside the Mortlake / Stag Brewery redevelopment, which shapes local planning policy and design expectations.
Property values: around £450,000 for a flat and £900,000-£1.4m for a house — a useful gauge of the build value an extension or loft adds in SW14.
Borough character: Highest conservation area coverage in London; Royal Parks and Thames corridor add heritage layers; design quality heavily scrutinised.
Measured existing survey, photographic record, Article 4 and conservation check specific to Mortlake 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 Edwardian and inter-war terraces and semis around Christchurch Road and Sheen Lane suit side-return, rear 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 Richmond's checklist.
The former Stag Brewery site at Mortlake is being redeveloped into homes, a school and riverside public space, one of the borough's largest schemes, supporting values across SW14. For a house project the binding controls remain Permitted Development limits and the local conservation area, which we check for your address.
Usually yes on the semis and terraces — a hip-to-gable plus rear dormer within the volume allowance, confirmed by a Lawful Development Certificate, provided you're not in the Mortlake or East Sheen conservation areas. We check the constraints for your road and draw it for Building Control.
With SW14 houses around £900,000-£1.4m and the appeal of Richmond Park on the doorstep, a side-return or loft adds family space worth well above the build and drawing cost. Our fixed fee keeps the professional cost predictable on these Edwardian and inter-war houses.
Our fixed fee for house extension drawings in Mortlake starts at £1,225 — no hourly billing. With Mortlake property at around £450,000 for a flat and £900,000-£1.4m for a house, the professional drawing fee is a small fraction of the value the work adds to SW14's edwardian and inter-war terraces and semis around. Richmond Council charges its own statutory application fee on top (currently £258 for a householder planning application, £578 for a full application). We quote the drawings as one fixed price and the free site survey covers every SW14 address.
For a SW14 project across Mortlake, East Sheen, Sheen, North Sheen 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 Richmond Council (8 weeks for a householder application). We carry the Mortlake application through every officer query to the decision.
Mortlake (SW14) sits primarily in Richmond upon Thames, so applications are decided by Richmond Council. Article 4 in force in the borough: No. Conservation areas within SW14 include Mortlake / The Green, East Sheen, Sheen Common, 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 Mortlake — 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 Richmond Council Building Control or an approved inspector. On SW14'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. With Mortlake (SW14) property at around £450,000 for a flat and £900,000-£1.4m for a house, a well-designed extension or loft typically returns more than it costs in added floor area and sale value, while our fixed drawing fee from £1,225 keeps the professional cost predictable. 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 SW14 homes.
From £840.
From £840.
From £1,225.
From £1,575.
From £995.
From £1,950.
From £350.
From £540.
From £450.
From £1,225.
Pick a slot that suits you. No obligation and no sales pressure — just straight answers on your planning route, fixed fee and timescale.
Every SW14 postcode district we draw in, the stock that dominates it and the authority that validates a house extension there. SW14 fees below are the statutory England rates for 2026, not house extension estimates.
| Postcode | Area | Dominant stock | What it means for a house extension |
|---|---|---|---|
| SW14 | Mortlake / East Sheen | Edwardian villas, 1930s semi-detached | A house extension at an SW14 address in Mortlake / East Sheen is determined by Richmond Council under its own Local Plan policies for Mortlake / East Sheen. |
| SW14 | East Sheen | Edwardian villas, 1930s semi-detached | East Sheen sits inside SW14; house extension proposals here are determined by Richmond Council. |
| SW14 | Mortlake | Victorian and Edwardian terraces | Mortlake sits inside SW14; house extension proposals here are determined by Richmond Council. |
| SW13 | Barnes | Georgian villas, Edwardian terraces | Adjoining district to SW14, also inside Richmond upon Thames for house extension purposes. |
| TW1 | Twickenham | Georgian fragments, Victorian terraces, Edwardian villas | Adjoining district to SW14, also inside Richmond upon Thames for house extension purposes. |
| TW2 | Twickenham / Whitton | Georgian fragments, Victorian terraces, Edwardian villas | Adjoining district to SW14, also inside Richmond upon Thames for house extension purposes. |
Roof pitch, wall build-up and plot depth change every few SW14 streets, and each one changes what a house extension can achieve at that address.
SW14 (Mortlake / East Sheen) conservation designations: there are 72 across Richmond Council, Kew Green, Hampton Wick, Twickenham Riverside among them. Designation costs a SW14 (Mortlake / East Sheen) owner the permitted-development route: a house extension then needs a £258 householder application over 8 weeks, in place of the £120 prior approval route that takes 6 weeks. Ham Common is the SW14 (Mortlake / East Sheen) designation that most often changes a house extension design.
SW14 (Mortlake / East Sheen) permitted development status: there is no borough-wide direction from Richmond Council, so a house extension at a SW14 address is normally still permitted development. We certify that with a £129 Lawful Development Certificate rather than leaving a SW14 (Mortlake / East Sheen) sale to argue it later.
SW14 (Mortlake / East Sheen) housing stock: Georgian in Richmond Green and Twickenham; Edwardian villas in Barnes and East Sheen; 1930s semi-detached in Whitton; riverside cottages along the Thames. Highest conservation area coverage in London; Royal Parks and Thames corridor add heritage layers; design quality heavily scrutinised. Read that before choosing a house extension route in SW14 (Mortlake / East Sheen) — construction, not postcode, sets what is achievable. House extensions in SW14 (Mortlake / East Sheen) start at £1,225 on a fixed fee, or £1,750 for the Complete package covering both Richmond Council submissions.
Sources for this SW14 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.
Free fixed quote in 60 seconds. From £1,225. MCIAT chartered.
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