Project guideGPDO Class C

Roof alteration in Lambeth: Planning Permission Guide

What you need to know about roof alterations in Lambeth — re-roofing, rooflights, and changing materials.

84%
approved in Lambeth
£548
application fee
8 wks
typical decision
≤0.15m
rooflight proud

Based on 44 decided applications in Lambeth over 12 months (37 granted, 7 refused).

Lambeth has numerous conservation areas including Clapham, Brixton, Herne Hill, Stockwell, and Kennington. The borough has substantial Article 4 coverage restricting external alterations to Victorian and Edwardian terraces, particularly around Clapham and Stockwell. Listed buildings cluster around Kennington Park and Lambeth Palace. The Thames frontage adds flood zone considerations for properties in Vauxhall and Nine Elms.

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Recent roof alteration decisions in Lambeth

The 5 most recent decided applications. Addresses redacted to postcode area.

Granted

Addition of one roof light to flat 4.

SE52026-07-27
Granted

Erection of a 2x conservatory with Photovoltaic panels at 4th floor roof level for penthouse 1 and 2.

SW92026-07-27
Granted

Replacement of the rear return roof from flat roof to pitched roof with 2no. roof lights; replacement of the second floor side window wit…

SW92026-07-24
Granted

Approval of details pursuant to Condition 4 (full details of the existing and proposed windows) for planning permission 25/03277/FUL (Rep…

SW82026-07-15
Granted

Approval of details pursuant to conditions 5 (Cycle parking), 8 (Urban Greening Factor), 9 (Green roofs), 12 (Photovoltaic (PV) arrays), …

SW162026-07-08

These are borough-wide. See the 5 nearest to your address.

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Permitted Development Rules

Class CPart 1

Any other alteration to the roof of a dwellinghouse

GPDO 2015, Schedule 2, Part 1, Class C

Roof alterations (other than dormers and loft conversions) are covered by Part 1, Class C of the GPDO. The key rule is that the alteration must not project beyond the existing roof plane.

Key dimension limits

Must not project beyond existing roof planeMaterials must match existing

These are the maximum GPDO limits for a detached house with no constraints. Your actual limits depend on your property type, location, and any planning restrictions.

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Typical Costs in London

Roof alteration costs vary depending on the scope — adding rooflights is much cheaper than a full roof replacement.

Roof alterationLondon

Cost per m²

£800£2,000

construction rate

Typical total

£5,000£15,000

Typically includes

MaterialsLabourScaffolding

Typically excludes

Planning application feeBuilding regs fee

Covers re-roofing, changing roof materials, adding rooflights. Full roof replacement is at the higher end.

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Which Professionals Do You Need?

Most roof alterations don't need an architect, but a roofing contractor or draughtsperson can prepare any required drawings.

A draughtsperson or architectural technician can prepare any drawings needed. A full architect may not be necessary.

Architect / designerOptional

Roof alterations may need drawings for Building Regulations, but a draughtsperson or roofing contractor can often provide these.

Typical fee: £500£2,000 (Basic drawings if needed)

Structural engineerNot needed
Party wall surveyorNot needed
Planning consultantNot needed

This guidance is based on a typical semi-detached house with no special constraints. Listed buildings, conservation areas, and attached properties may require additional professional input.

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Conservation Areas & Listed Buildings

In conservation areas, roof alterations that change the appearance of the roof may be more tightly controlled. Materials should match the existing roof.

Conservation areas

Properties in conservation areas often have reduced permitted development rights. Some project types (like side extensions) lose PD rights entirely. An Article 4 Direction can remove additional PD rights.

Listed buildings

Listed buildings (Grade I, II*, or II) have no permitted development rights at all. Any external alteration requires Listed Building Consent in addition to any planning permission. An architect experienced in heritage work is essential.

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Frequently Asked Questions

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