The area this guide covers
This guide treats the South Hampstead conservation area, about 59.2 hectares in the London Borough of Camden, as the area. Within that boundary the planning record has several layers: as well as the conservation-area designation itself, planning.data.gov.uk shows two named Article 4 directions that each cover all of it.
Almost every dwelling in the surrounding statistical areas is a flat, so lease terms and shared structure come up as often as planning controls. Borough-wide context is in the Camden guide.
Designation, directions and housing stock
Every statement below links to the public record it comes from; sources were re-checked on .
Designation
The planning.data.gov.uk entry for the designation carries Camden reference CA36, a record start date of 1 August 1988 (the date the dataset uses for a designation or its latest boundary change) and a mapped area of about 59.2 hectares.
Camden's conservation area web page and its appraisal and management strategy are the local documents to read alongside that national record.
Two named Article 4 directions
Two named directions in the Article 4 records held on planning.data.gov.uk each cover 100% of the conservation area.
The first is named Basements and has a start date recorded as 3 October 2016, so it is checked before any basement or lower-ground excavation is planned.
The second is the South Hampstead Conservation Area Non-immediate Article 4, with a start date of 9 June 2026 on the same dataset.
A non-immediate direction comes into force at a later date than it is made, so the planning.data entry is read with Camden's heritage and conservation Article 4 page to confirm which permitted development rights are now withdrawn and from when.
With both directions spanning the whole boundary on the Article 4 dataset, any external alteration or basement proposal should be checked with Camden before it is assumed to be permitted development.
Very little listing
Inside the 59.2-hectare boundary the NHLE listed-building data returns just 2 list entries, both Grade II, as queried on 1 November 2026.
So few entries means conservation-area control, not listed building consent, governs nearly every alteration here, although the NHLE record is still checked for any address where listing is suspected.
London Clay with no cover
At each of the five sample points, BGS geology at 1:50,000 shows London Clay Formation (clay, silt and sand), with no superficial deposits recorded on top.
London Clay changes volume with its moisture content, and street and garden trees can dry it out in summer, so the BGS geology viewer is a reminder to look at tree positions, drains and any past underpinning when cracks appear.
Excavating a basement in clay also raises groundwater and neighbouring-structure questions, which is one reason the mapped geology is read together with the Basements direction before a scheme is costed.
Flood zones
Nothing inside the boundary falls in Flood Zone 2 or Flood Zone 3 on the Flood Map for Planning.
Planning flood zones cover rivers and the sea only, disregard defences and are not drawn for single buildings, so any basement or lower-ground flat is looked up on the long-term flood risk service for its surface-water result.
Flats in older buildings
Five statistical areas, LSOAs E01000966, E01000962, E01000965, E01000964 and E01000968, give about 4,130 dwellings in the Valuation Office Agency's 2025 stock counts, with each count rounded to the nearest 10.
Of those dwellings, 78.0% date from before 1900 in the VOA build-period figures, and only 1.5% to 2000 or later, with 9.7% from 1945-1972 and 5.6% from 1919-1939.
By type the VOA figures show 92.5% flats or maisonettes, 2.4% terraced houses, 1.5% semi-detached houses and 1.0% detached houses.
Put together, those two shares mean at least seven in ten dwellings are flats in buildings that the VOA dates to before 1900.
Bands F to H hold 29.1% of these dwellings, with bands D and E the largest at 26.2% and 27.4%, in the VOA band counts.
For a flat in an older converted building, the lease plan, the split of repair liability for the roof, main walls and foundations, and any recent major works matter as much as the flat itself, and the VOA stock figures show how typical that case is here.
Published guides for this conservation area
Each local guide below takes a single kind of instruction in depth, and the matching practice page explains the service in general terms.
Areas next door
The Camden guide sits above this one, and the neighbouring guides for Swiss Cottage, West Hampstead, Belsize Park, St John's Wood and Kilburn each cover their own records.
South Hampstead questions
Do the Article 4 directions affect my flat?
Possibly. Two named directions, Basements and the South Hampstead Conservation Area Non-immediate Article 4, each span the entire boundary according to planning.data.gov.uk. Which rights they remove, and from when, should be confirmed with Camden before any external change or excavation.
Can I add a basement under a house or flat here?
That turns on planning as much as engineering. A direction named Basements covers the whole conservation area on planning.data.gov.uk, so a basement proposal should be assumed to need a planning application. Mapped London Clay, groundwater and the neighbouring buildings then shape what can be designed.
How many listed buildings are inside the boundary?
Very few. The NHLE data returns 2 list entries inside the conservation area, both Grade II. Conservation-area controls therefore matter far more than listing for most addresses, although the record should still be checked for any building you think may be listed.
What date does the national record give for the conservation area?
The planning.data.gov.uk record gives a start date of 1 August 1988, under Camden reference CA36, with a mapped area of about 59.2 hectares; the dataset uses that field for a designation or its latest boundary change. Camden's own appraisal and management strategy is the local document for the designation history.
What share of homes nearby are flats?
In the five surrounding LSOAs, the VOA 2025 tables class 92.5% of about 4,130 dwellings as flats or maisonettes, while 78.0% of dwellings date from before 1900. Lease terms, shared roofs and service charges are therefore part of nearly every purchase in these streets.
What should a flat buyer send before an inspection?
The address and floor, the lease or its key clauses, recent service charge accounts, any notice of major works, and details of alterations such as a loft or basement conversion. If the freeholder holds a recent repair or insurance report for the building, mention it so the inspection can focus on what is still unknown.
How we work on an instruction
Hampstead Chartered Surveyors is a RICS-regulated firm (RICS Regulated Firm No. 923064) working from its registered Hampstead NW3 office. The firm does not claim premises, staff or completed instructions in an individual locality, and it does not treat a neighbourhood name as evidence about a particular building.
An instruction starts with the full address, the decision the client faces and the documents already available, such as leases, drawings, notices or earlier reports. The scope, fee and inspection date are confirmed in writing only after that review, and access to roofs, lofts, basements or common parts is agreed before the visit.
Reports include RICS Level 2 and Level 3 home surveys, building and defect investigations, party wall appointments, reinstatement cost assessments, contract administration and schedules of condition. Each report records what was inspected, what could not be seen and what further investigation the evidence supports.
Public datasets such as the conservation-area register, the National Heritage List for England, British Geological Survey mapping, the Environment Agency flood map and Valuation Office Agency housing statistics describe areas rather than individual properties. They frame questions before an inspection; they never replace it.
Reviewed by Savas Bulduk BSc (Hons) MRICS, Director & Chartered Building Surveyor at Hampstead Chartered Surveyors & Building Consultancy. Last reviewed: . Our people · RICS firm record