Bromley's most space-efficient loft solution when PD-route dormers are blocked. Our chartered team designs mansards that get approved in Bromley conservation areas — with heritage statements and planning officer negotiation built in.
Bromley's most space-efficient loft solution when PD-route dormers are blocked. Our chartered team designs mansards that get approved in Bromley conservation areas — with heritage statements and planning officer negotiation built in.
Housing stock in Bromley: 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.
Character: Largest London borough by area; substantial Green Belt; conservation areas in most town centres; generally permissive elsewhere.
We check against Bromley Council's mansard design guide and design to match the terrace.
Required for Bromley's conservation areas — demonstrates the mansard respects character and townscape.
Accurate photomontage showing how the mansard sits alongside neighbours — often decisive at Bromley Council committee.
Mansards invariably trigger Party Wall notices in Bromley's dense terraced streets. Structural package includes new ridge, tie beams, floor joists.
Full liaison with Bromley 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 Bromley homeowners ask every week about mansard roof extensions.
Start a free quote →Mansards in Bromley are less common historically — Bromley 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 Bromley 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. Bromley Council's design guide (where published) takes precedence on detail.
Often yes, but Bromley Council favours applications supported by wider street precedents. Where mansards already exist nearby in Bromley, approval is far more likely. We review street precedents at the feasibility stage.
Our architectural fees for a Bromley mansard start at £1,575 (planning + building regs + structural + heritage statement). Typical Bromley 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 Bromley's large 1930s detached and semi-detached in Chislehurst and Bickley terraced context.
We cover all Bromley postcodes — {postcodes} — and have submitted mansard applications across the borough. Our heritage statement and design-and-access statement are included in every mansard package.
Bromley's large 1930s detached and semi-detached in Chislehurst and Bickley 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 Bromley 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 Bromley 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 Bromley 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 Bromley roof line — dormer, mansard, hip-to-gable, L-shape, Velux. LDC or full planning rou...
From £1,225. The whole spectrum — rear extensions, side returns, wraparounds, double-storey, basement digs. Planning-led design with ...
From £995. Turn your unused Bromley garage into a bedroom, home office or open-plan kitchen-diner. Planning route assessment, full ...
From £1,950. Full architectural technology service for basement digs and cellar conversions in Bromley — structural underpinning desi...
From £350. Chartered structural engineer calculations for every residential intervention in Bromley — steel beams, lintels, pad fou...
From £540. Fixed-fee measured surveys across Bromley from £540 — floor plans, elevations and sections to ±3mm accuracy. Leica Disto...
From £450. End-to-end Party Wall Act 1996 service for Bromley — Section 1, 3 and 6 notices, schedule of condition surveys, party wa...
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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