Basement in Wandsworth: Planning Permission Guide
What you need to know about basement extensions in Wandsworth — planning requirements, costs, and professional guidance.
Based on 122 decided applications in Wandsworth over 12 months (106 granted, 16 refused).
Wandsworth has numerous conservation areas including Battersea, Clapham Common West Side, Wandsworth Common, and Putney. Article 4 Directions restrict external alterations to Victorian terraces, particularly around Clapham and Battersea. Listed buildings cluster around Battersea Park and Putney High Street. Flood zones along the Thames affect riverside properties in Battersea, Putney, and Wandsworth.
Recent basement decisions in Wandsworth
The 5 most recent decided applications. Addresses redacted to postcode area.
T001 - Sessile Oak in back garden of 7 Blenkarne Road which requires root pruning to allow space for building agreed in planning permissi…
Alterations including excavation to enlarge basement including formation front lightwell and alterations to side boundary wall.
Alterations and extension to existing rear additions including provision of new glazed doors and windows/rooflights and formation of grou…
Details of Landscape and Ecological Enhancement Plan pursuant to condition 8 of planning permission dated 13/08/2025 ref 2024/3766 (Demol…
Change of use of ground and basement floors from Class E (commercial, business and service) to a dog daycare and grooming salon (Sui Gene…
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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