Porch in Lewisham: Planning Permission Guide
Everything you need to know about building a porch in Lewisham — PD rules, costs, and when you need planning permission.
Check if your porch qualifiesPorchs in Lewisham at a glance
application fee
weeks typical
Lewisham has conservation areas in Blackheath, Telegraph Hill, Brockley, Lee Manor, and Forest Hill. Article 4 Directions restrict window and door alterations in several Victorian conservation areas. The borough mixes dense inner-city housing in the north with more suburban character in the south. Flood zones along the Ravensbourne and Quaggy rivers restrict outbuilding classes for riverside properties.
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Permitted Development Rules
Porches
GPDO 2015, Schedule 2, Part 1, Class D
Porches are covered by Part 1, Class D of the GPDO. They have simple, clear rules: stay under 3 square metres, under 3 metres high, and at least 2 metres from the highway.
Key dimension limits
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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Check my limitsTypical Costs in London
Porches are one of the more affordable home improvements, with costs depending mainly on materials and design.
Cost per m²
construction rate
Typical total
Based on 2–4 m²
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Costs depend heavily on materials and finish — a simple UPVC porch is at the low end, brick-built with tiled roof at the high end.
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Get my estimateWhich Professionals Do You Need?
Porches are relatively simple structures. In most cases, a builder can handle the project without needing an architect.
A draughtsperson or architectural technician can prepare any drawings needed. A full architect may not be necessary.
Porches are simple structures. A builder or draughtsperson can usually prepare any drawings needed.
Typical fee: £500–£1,500 (Basic drawings)
May apply if the work is within 3 metres of a shared boundary. Check with your builder.
Typical fee: £700–£1,500 (per neighbour (if applicable))
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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Get personalised guidanceConservation Areas & Listed Buildings
In conservation areas, the same PD rules apply to porches, but you should use materials sympathetic to the area character.
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 (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.
Check if your property is in a conservation area or has other planning constraints.
Check my propertyFrequently Asked Questions
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