Rear Dormer Loft Conversion Drawings in Bromley

Where in Bromley does a rear dormer actually get determined?

Each Bromley postcode district we draw in, the housing that dominates it, and which authority actually validates a dormer there. The charges shown below are the statutory England application fees for 2026, not an estimate of what a dormer costs to build.

What changes about a rear dormer in each part of Bromley?

Pitch, wall construction and plot depth can differ between one Bromley street and the next, and each of those differences alters what a dormer will realistically deliver at a given address.

• Keston (BR2) — a rear dormer in Keston starts from edwardian villas, 1930s semi-detached, and Keston reads as Edwardian and 1930s village. The deeper Edwardian rear slope takes a full-width dormer without breaching the 40 m³ or 50 m³ volume limits on most of these houses in BR2. Bromley Council assesses Keston rear dormers against its own Keston character guidance, and the location plan we draw for Keston references Keston Ponds.
• Penge (SE20) — Victorian and Edwardian terraces defines Penge, where victorian and edwardian terraces set what a rear dormer can do. Full-width rear dormers on Victorian terraces here are the default across SE20. Any Penge rear dormer is validated by Bromley Council, with Penge East station the usual Penge reference point on the site plan.
• Bromley (BR1, BR2) — Victorian and Edwardian centre defines Bromley, where victorian terraces, edwardian villas, post-war flats set what a rear dormer can do. Full-width rear dormers on Victorian terraces here are the default across BR1. Any Bromley rear dormer is validated by Bromley Council, with Bromley High Street the usual Bromley reference point on the site plan.
• Beckenham (BR3) — a rear dormer in Beckenham starts from edwardian villas, 1930s semi-detached, and Beckenham reads as Edwardian villas, 1930s semi-detached. The deeper Edwardian rear slope takes a full-width dormer without breaching the 40 m³ or 50 m³ volume limits on most of these houses in BR3. Bromley Council assesses Beckenham rear dormers against its own Beckenham character guidance, and the location plan we draw for Beckenham references Beckenham Junction.
• Chislehurst (BR7) — Large 1930s detached, conservation defines Chislehurst, where 1930s detached, edwardian villas set what a rear dormer can do. The deeper Edwardian rear slope takes a full-width dormer without breaching the 40 m³ or 50 m³ volume limits on most of these houses across BR7. Any Chislehurst rear dormer is validated by Bromley Council, with Chislehurst Caves the usual Chislehurst reference point on the site plan.
• Bickley (BR1) — a rear dormer in Bickley starts from 1930s detached, edwardian villas, and Bickley reads as 1930s detached, conservation. The deeper Edwardian rear slope takes a full-width dormer without breaching the 40 m³ or 50 m³ volume limits on most of these houses in BR1. Bromley Council assesses Bickley rear dormers against its own Bickley character guidance, and the location plan we draw for Bickley references Bickley station.
• Orpington (BR5, BR6) — 1930s semi-detached, post-war defines Orpington, where 1930s semi-detached set what a rear dormer can do. Hip-to-gable plus rear dormer is the standard sequence on these 1930s semis across BR5. Any Orpington rear dormer is validated by Bromley Council, with Orpington High Street the usual Orpington reference point on the site plan.

Does Bromley planning policy restrict a rear dormer?

Conservation areas covering Bromley: Bromley Council runs 48, and Bickley, Bromley Town, Chislehurst are the ones Bromley owners meet most. A rear dormer inside a Bromley conservation area loses permitted development, so the Bromley submission is a householder application at £548 decided in 8 weeks — not a £249 prior approval decided in 6 weeks. In Bromley Town a rear dormer is judged on the street elevation first.

Bromley has no borough-wide Article 4 direction: the council has not withdrawn permitted development rights across its area, so a dormer on a house outside a designated boundary normally keeps them. Keeping them is not the same as proving you had them, which is why an SE20 owner in particular still wants the £274 certificate on file: that district runs across into Croydon, and the two councils have not designated the same streets.

What Bromley is built from: 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. That mix decides the rear dormer route in Bromley more than the postcode does, and it is what a Bromley Council case officer reads first. A householder application costs £548 paid to Bromley Council direct, with 8 weeks to a decision once validated.

What happens if a Bromley property sits on a boundary?

• Southwark — the Southwark boundary runs against Bromley, so a rear dormer a street from Bromley is decided by Southwark Council instead. Southwark runs 43 conservation areas across SE1 and its neighbours, which is why rear dormers priced for Bromley are re-checked against Southwark policy whenever the Bromley address sits on that edge.
• Lewisham — the Lewisham boundary runs against Bromley, so a rear dormer a street from Bromley is decided by Lewisham Council instead. Lewisham runs 30 conservation areas across SE3 and its neighbours, which is why rear dormers priced for Bromley are re-checked against Lewisham policy whenever the Bromley address sits on that edge.
• Greenwich — cross the Bromley boundary and Greenwich Council takes the rear dormer instead, applying 20 conservation areas of its own around SE3. We re-price rear dormers at the Bromley edge because Greenwich policy and Bromley policy rarely align on rear dormer depth.
• Bexley — adjoining Bromley, with 16 conservation areas centred on DA1. A rear dormer on the far side of the Bromley line is determined by Bexley Council, so the Bromley quote for rear dormers is checked against Bexley guidance before it is issued.

Sources for this Bromley rear dormer 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.