SE15 is decided by Southwark Council. The Bellenden and Holly Grove conservation areas cover much of Peckham's best Victorian villa stock, where the council's design guidance and a Heritage Statement matter. Outside them, the dense terraced grids around Nunhead and Peckham Rye are strong rear-extension and loft candidates.


This page covers one part of the borough. For the full picture — fees, timelines and the council's current position — read mansard roof extensions in Southwark.
A mansard roof extension adds a full storey behind a new sloping front face — a strong option on SE15's terraces in Peckham where a standard dormer is too small. Southwark Council scrutinises mansards on townscape and precedent, especially within Holly Grove, Bellenden, Nunhead Green, Peckham Rye; we design to the borough's roof guidance with a Heritage Statement where the setting requires it.
Peckham's most space-efficient loft solution when PD-route dormers are blocked. Our chartered team designs mansards that get approved in Peckham conservation areas — with heritage statements and planning officer negotiation built in.
Across Peckham, Nunhead, Bellenden, Holly Grove, Peckham Rye in SE15, the dominant property is victorian terraces across peckham and nunhead, grand double-fronted villas in the holly grove and bellenden conservation areas, and ex-industrial warehouse conversions near the bussey building and copeland park. That stock shapes what mansard roof extensions looks like here: the right approach for a period terrace differs from a mansion-block flat or a new-build, and Southwark Council judges each on design quality and neighbour impact. We survey the specific Peckham property, confirm the planning route — Permitted Development, a Lawful Development Certificate, or full planning — and draw a council-ready set tailored to the SE15 streetscape.
Housing stock in SE15: Victorian terraces across Peckham and Nunhead, grand double-fronted villas in the Holly Grove and Bellenden conservation areas, and ex-industrial warehouse conversions near the Bussey Building and Copeland Park.
Within the district: Peckham, Nunhead, Bellenden, Holly Grove, Peckham Rye.
Conservation areas: Holly Grove, Bellenden, Nunhead Green, Peckham Rye. Inside these, most external work needs full planning and a Heritage Statement.
Getting around SE15: Peckham Rye and Queens Road Peckham (Overground/Southern), Nunhead (Thameslink/Southeastern).
Regeneration: Peckham falls within or beside the Peckham town centre / Old Kent Road Opportunity Area fringe, which shapes local planning policy and design expectations.
Property values: approx £600k–£1.2m for houses, £400k–£675k for flats (Land Registry, 2024) — a useful gauge of the build value an extension or loft adds in SE15.
Borough character: Dulwich Estate private planning scheme affects much of SE21 and SE22; Southwark planning for rest of borough; strong heritage context.
We check against Southwark Council's mansard design guide and design to match the terrace.
Required for Peckham's conservation areas — demonstrates the mansard respects character and townscape.
Accurate photomontage showing how the mansard sits alongside neighbours — often decisive at Southwark Council committee.
Mansards invariably trigger Party Wall notices in Peckham's dense terraced streets. Structural package includes new ridge, tie beams, floor joists.
Full liaison with Southwark Council planning officer, committee representation if called in.
Part L thermal, Part B fire (critical on mansards), Part E acoustic separation.
Single planning or building-regs submission.
Planning + building regs + structural.
Listed, conservation or complex sites.

The Bellenden and Holly Grove conservation areas in Peckham SE15 protect grand double-fronted Victorian villas, so rear extensions, loft dormers and external changes need full planning and a Heritage Statement addressing Southwark's character appraisal. The council is design-led here; subordinate rear additions in matching brick and traditional detailing have a good approval record. We confirm your street's conservation status before quoting.
Many do. The Victorian terraces around Nunhead and Peckham Rye in SE15 that sit outside the conservation areas keep permitted-development rights for single-storey rear extensions (up to 3m attached) and rear dormer lofts, decided by Southwark Council. Properties near Nunhead Green or within the Peckham Rye conservation area need full planning. We map your exact address first.
Peckham SE15's two-storey Victorian terraces take a rear or L-shaped dormer loft well, adding a double bedroom and bathroom. The larger Bellenden and Holly Grove villas can sometimes take a fuller mansard or hip-to-gable where precedents exist, subject to conservation-area design control. Building Regulations cover fire escape, floor structure and insulation; Party Wall notices are normally required.
With Peckham property at approx £600k–£1.2m for houses, £400k–£675k for flats (Land Registry, 2024), the professional drawing fee is a small fraction of the value the work adds to SE15's victorian terraces across peckham and nunhead, grand. Southwark Council charges its own statutory application fee on top (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 SE15 address.
For a SE15 project across Peckham, Nunhead, Bellenden, Holly Grove, Peckham Rye, 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 Southwark Council (8 weeks for a householder application). We carry the Peckham application through every officer query to the decision.
Peckham (SE15) sits primarily in Southwark, so applications are decided by Southwark Council. Conservation areas within SE15 include Holly Grove, Bellenden, Nunhead Green, Peckham Rye, 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 mansard roof extensions in Peckham — 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 Southwark Council Building Control or an approved inspector. On SE15'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 Peckham (SE15) property at approx £600k, £1.2m for houses, £400k, £675k for flats (Land Registry, 2024), a well-designed extension or loft typically returns more than it costs in added floor area and sale value. 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 SE15 homes.
Planning history and precedent stop at the borough line, so the comparable approvals nearby may sit elsewhere. See all services in SE5, SE21, SE22 and SE24.
Pick a slot that suits you. No obligation and no sales pressure, just straight answers on your planning route.
Every SE15 postcode district we draw in, the stock that dominates it and the authority that validates a mansard roof extension there. SE15 fees below are the statutory England rates for 2026, not mansard roof extension estimates.
| Postcode | Area | Dominant stock | What it means for a mansard roof extension |
|---|---|---|---|
| SE15 | Peckham / Nunhead | Victorian terraces, post-war estates | A mansard roof extension at an SE15 address in Peckham / Nunhead is determined by Southwark Council under its own Local Plan policies for Peckham / Nunhead. |
| SE15 | Peckham | Victorian terraces, post-war estates | Peckham sits inside SE15; mansard roof extension proposals here are determined by Southwark Council. |
| SE15 | Nunhead | Victorian terraces | Nunhead sits inside SE15; mansard roof extension proposals here are determined by Southwark Council. |
| SE1 | Bermondsey / Borough / Waterloo | Georgian terraces, post-war flats, new-build | Adjoining district to SE15, also inside Southwark for mansard roof extension purposes. |
| SE5 | Camberwell | Georgian villas, Victorian terraces | Adjoining district to SE15, also inside Southwark for mansard roof extension purposes. |
| SE16 | Bermondsey / Rotherhithe | Warehouse conversions, Georgian terraces, new-build | Adjoining district to SE15, also inside Southwark for mansard roof extension purposes. |
Roof pitch, wall build-up and plot depth change every few SE15 streets, and each one changes what a mansard roof extension can achieve at that address.
How designation changes a SE15 (Peckham / Nunhead) mansard roof extension: Southwark Council maintains 43 conservation areas, including Borough, Camberwell Grove, Bermondsey Street. Inside any of them a SE15 (Peckham / Nunhead) mansard roof extension cannot rely on permitted development, and the route becomes a £548 householder application determined in 8 weeks rather than a £249 prior approval in 6 weeks. Camberwell Grove sets the tone for SE15 (Peckham / Nunhead) casework.
What Article 4 removes near SE15 (Peckham / Nunhead): Article 4 for HMOs borough-wide; additional Article 4 for office-to-residential in Bermondsey and Elephant & Castle. Before pricing a mansard roof extension we check whether the SE15 address is inside the mapped area, because Southwark Council draws the SE15 (Peckham / Nunhead) boundary street by street rather than across the whole of SE15 (Peckham / Nunhead).
The building fabric around SE15 (Peckham / Nunhead): Georgian and Regency in Bermondsey and Borough; Victorian terraces in Camberwell and Peckham; Dulwich Estate controlled housing; riverside new-build. Dulwich Estate private planning scheme affects much of SE21 and SE22; Southwark planning for rest of borough; strong heritage context. A mansard roof extension in SE15 (Peckham / Nunhead) is scoped against that stock first, because it decides whether the scheme runs as permitted development, a £274 Lawful Development Certificate, or a full £548 application to Southwark Council.
Sources for this SE15 mansard roof 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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Local values run approx £600,000–£1.2m for houses, £400,000–£675,000 for flats. Source: Land Registry, 2024.
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