Basement in Greenwich: Planning Permission Guide
What you need to know about basement extensions in Greenwich — planning requirements, costs, and professional guidance.
Based on 25 decided applications in Greenwich over 12 months (21 granted, 4 refused).
Greenwich has a UNESCO World Heritage Site at Maritime Greenwich, which triggers Article 2(3) designated land rules — standard permitted development dimension limits are effectively halved near the WHS. Conservation areas include Blackheath, Charlton Village, and Eltham. Listed buildings are particularly concentrated around the Royal Naval College and Greenwich Park. The Thames frontage adds flood zone considerations for properties along the river.
Recent basement decisions in Greenwich
The 5 most recent decided applications. Addresses redacted to postcode area.
Construction of rear basement and ground floor extension with terrace area and railings. Relocation of external rear staircase. Alteratio…
Change of use at basement, ground floor and first floor levels and of building at rear from commercial (Use Class E) to residential (Use …
Prior Approval is sought to change the use of rear section of basement from (Class E) to form 2 x Studio flats.
Construction of a part one and part two-storey building with basement for office use (Class E).
Excavation of front garden, installation of dropped kerb and all associated works.
These are borough-wide. See the 5 nearest to your address.
Check your address freePermitted Development Rules
Basement excavation requires a full planning application.
Basement excavation does not have permitted development rights under Part 1 of the GPDO. A full planning application is always required.
Typical Costs in London
Basements are among the most expensive home improvement projects. Costs vary enormously depending on depth, ground conditions, and access.
Cost per m²
construction rate
Typical total
Based on 25–50 m²
Typically includes
Typically excludes
Basement projects are complex and costs vary enormously depending on depth, ground conditions, waterproofing, and access. Professional advice is essential.
Get a personalised cost estimate based on your actual basement dimensions.
Get my estimateWhich Professionals Do You Need?
Basement projects are complex and always require specialist professional input — an architect, structural engineer, and usually a party wall surveyor.
You'll need an architect, a structural engineer, and a party wall surveyor for this project.
Basement projects are complex and require specialist architectural and structural design.
Typical fee: £5,000–£15,000 (Full architectural service)
Basement excavation requires detailed structural engineering for underpinning, retaining walls, and waterproofing.
Typical fee: £2,000–£5,000
Basement excavation almost always triggers the Party Wall Act due to work near neighbouring foundations.
Typical fee: £700–£1,500 (per neighbour)
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.
Find out exactly which professionals you need for your basement.
Get personalised guidanceConservation Areas & Listed Buildings
In conservation areas, basement applications receive additional scrutiny. The council will consider the impact on neighbouring properties and the character of the area.
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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