Merton's most space-efficient loft solution when PD-route dormers are blocked. Our chartered team designs mansards that get approved in Merton conservation areas — with heritage statements and planning officer negotiation built in.
Merton's most space-efficient loft solution when PD-route dormers are blocked. Our chartered team designs mansards that get approved in Merton conservation areas — with heritage statements and planning officer negotiation built in.
Housing stock in Merton: Victorian villas in Wimbledon; Edwardian terraces in Tooting and Colliers Wood; 1930s semi-detached in Morden and Raynes Park; post-war flats in Mitcham.
Character: Wimbledon is heavily conservation-controlled; outer Merton (Morden, Mitcham) is permissive.
We check against Merton Council's mansard design guide and design to match the terrace.
Required for Merton's conservation areas — demonstrates the mansard respects character and townscape.
Accurate photomontage showing how the mansard sits alongside neighbours — often decisive at Merton Council committee.
Mansards invariably trigger Party Wall notices in Merton's dense terraced streets. Structural package includes new ridge, tie beams, floor joists.
Full liaison with Merton Council planning officer, committee representation if called in.
Part L thermal, Part B fire (critical on mansards), Part E acoustic separation.
Single planning or regs submission.
Planning + building regs + structural.
Listed, conservation, complex sites.
Direct answers to the questions Merton homeowners ask every week about mansard roof extensions.
Start a free quote →Mansards in Merton are less common historically — Merton Council considers each application on its merits. Rear mansards on suitable terraced or semi-detached properties, matching the roofscape, have a reasonable approval rate with the right design and supporting heritage commentary where relevant.
A 70° front slope is typical for Merton mansards — steep enough to maximise floor area while reading as a roof rather than a full additional storey. Front dormers should be small and symmetrical. Merton Council's design guide (where published) takes precedence on detail.
Often yes, but Merton Council favours applications supported by wider street precedents. Where mansards already exist nearby in Merton, approval is far more likely. We review street precedents at the feasibility stage.
Our architectural fees for a Merton mansard start at £1,575 (planning + building regs + structural + heritage statement). Typical Merton build costs are £90,000–£150,000 depending on size, complexity and access.
Full-height — typically 2.3–2.5m ceiling from the new floor. Unlike a dormer, which gives partial head height, a mansard provides a complete additional storey within Merton's victorian villas in Wimbledon terraced context.
We cover all Merton postcodes — {postcodes} — and have submitted mansard applications across the borough. Our heritage statement and design-and-access statement are included in every mansard package.
Merton's victorian villas in Wimbledon terraced stock is the natural context for mansard extensions — they were originally designed for Victorian and Edwardian rows. Feasibility depends on street precedent, conservation area status and party wall implications. We assess all three at the free site visit.
A mansard adds a full upper storey — typically 35–45m² of usable floor space. In Merton this often converts a 3-bed house to 4 or 5 beds. The steep front slope (70°) and flat top read as a roof, not a full floor, which is why Merton Council accepts them more readily than a simple box extension.
We cover every London borough with the same fixed-fee approach. If your property sits on a boundary, here are the neighbouring options.
We cover every architectural technology service in Merton with one chartered team.
From £840. A fixed-fee, end-to-end service — measured survey, scaled drawings, Design & Access Statement where required, Planning P...
From £840. A construction-ready drawing package compliant with every Approved Document — Part A structure, Part B fire, Part L ther...
From £1,225. Every loft type across every Merton roof line — dormer, mansard, hip-to-gable, L-shape, Velux. LDC or full planning rout...
From £1,225. The whole spectrum — rear extensions, side returns, wraparounds, double-storey, basement digs. Planning-led design with ...
From £995. Turn your unused Merton garage into a bedroom, home office or open-plan kitchen-diner. Planning route assessment, full b...
From £1,950. Full architectural technology service for basement digs and cellar conversions in Merton — structural underpinning desig...
From £350. Chartered structural engineer calculations for every residential intervention in Merton — steel beams, lintels, pad foun...
From £540. Fixed-fee measured surveys across Merton from £540 — floor plans, elevations and sections to ±3mm accuracy. Leica Disto ...
From £450. End-to-end Party Wall Act 1996 service for Merton — Section 1, 3 and 6 notices, schedule of condition surveys, party wal...
From £1,225. London's most popular loft type — the full-width rear dormer. Planning or Permitted Development route assessed for your ...
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Free quote in 60 seconds. Fixed fee from £1,575. MCIAT chartered.
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