Two small designations in a larger town
Orpington is a town in the London Borough of Bromley, and its two conservation areas covered here, The Priory and Broomhill, together extend to only about 8.1 hectares. Most of the town therefore lies outside these two boundaries, and the records below describe the two designations plus the statistical areas around them, not the whole town.
That distinction matters for planning, because an address inside either conservation area faces different controls from one a few streets away. The South East London guide gives the broader context for this corner of London.
What the datasets record for the two areas
Every statement below links to the public record it comes from; sources were re-checked on .
Two designations
The Priory, Orpington is Bromley conservation area CA25; planning.data.gov.uk gives it a designation date of 14 May 1985 and an area of about 6.6 hectares.
Broomhill, Orpington, reference CA24, is smaller at about 1.5 hectares and carries a designation date of 16 May 1989 on the same dataset.
With the two boundaries totalling about 8.1 hectares on the national conservation-area map, an address is checked against both lines, since standing just outside changes what can be done without consent.
Bromley's Town Centre SPD is the council's supplementary planning guidance for the centre and is worth reading for any property near it, whether or not it is in a conservation area.
No Article 4 polygon over either area appears on the Article 4 layer of planning.data.gov.uk, and because that absence is not confirmation from the council, Bromley is asked directly before permitted development rights are relied on.
Listed entries and Priory Gardens
Across both conservation areas the NHLE data returns 5 list entries for a query made on 1 November 2026, two of them Grade II* and three Grade II.
The two Grade II* entries are The Priory and the Church of All Saints.
Priory Gardens, on the register of parks and gardens at Grade II, shares about 1.53 hectares with the conservation areas, so a garden wall or rear extension near it can raise questions about the registered landscape as well as the designation.
Listing applies to a handful of buildings across the two areas, and it is the NHLE record for the specific address that settles whether listed building consent is in play.
Chalk under gravel
On the BGS bedrock layer at 1:50,000, four of the five sample points fall on Seaford Chalk Formation and one on Thanet Formation, a mix of sand, silt and clay.
Taplow Gravel Member sand and gravel is mapped over four points on the superficial layer of the same map, and the fifth has no superficial deposit recorded.
Chalk can contain solution features and gravel can be washed out by leaking drains, so where the geology viewer shows this pairing, a soakaway, a damaged drain run or a localised dip in a floor is followed up rather than assumed to be minor.
Thanet Formation varies between sandy and clayey beds, and where BGS mapping places a house on it, the possibility of different ground under different parts of the building is kept in mind.
No river or sea flood zone
No land in either area is shown as Flood Zone 2 or 3 on the planning map that the Environment Agency publishes, the Flood Map for Planning.
The zones cover only rivers and the sea, ignore defences and do not assess buildings, so surface water at an address is looked up separately with the government's long-term flood risk tool.
Homes in three surrounding LSOAs
For housing, three surrounding LSOAs, E01000788, E01000812 and E01000790, give about 2,590 dwellings in the VOA council tax stock statistics for 2025, where each count is rounded to the nearest 10.
Interwar dwellings lead the period breakdown at 39.8%, ahead of 23.6% from 2000 onwards, with 12.7% from 1945-1972, 9.3% from 1973-1999, 8.5% from 1900-1918 and 6.2% from before 1900.
By type, flats or maisonettes are 36.3%, semi-detached houses 22.4%, detached houses 18.5%, terraced houses 16.2% and bungalows 5.4% on the VOA property figures.
Council tax bands F to H cover 23.6% of these dwellings on the VOA band counts, with band D the largest at 30.1%.
The VOA figures pair a large interwar share with almost a quarter built since 2000, so the questions range from original 1930s detailing and later extensions to the lease and warranty position of a newer flat.
Orpington guides by type of instruction
Local guides on the left go into one instruction each for this town, while the practice pages on the right describe the service as a whole.
Other guides in Bromley and beyond
The Chislehurst, Bromley, Hayes, Bromley and Beckenham guides cover other parts of the same borough, Sidcup and Sevenoaks, in Kent, have their own guides, and the South East London guide lists the rest.
What people ask about The Priory and Broomhill
Which conservation areas does this guide cover?
Two: The Priory, Orpington, about 6.6 hectares, and Broomhill, Orpington, about 1.5 hectares. Together they cover about 8.1 hectares, so most addresses in the town fall outside both, and each property is checked against the mapped lines.
Is The Priory a listed building?
Yes. The Priory is listed at Grade II*, as is the Church of All Saints, and the NHLE data returns 5 list entries in total inside the two conservation areas. Priory Gardens is separately registered as a Grade II park and garden.
Is the town built on chalk?
In places. The BGS geology map shows Seaford Chalk at four of five sample points in the conservation areas, mostly under Taplow Gravel. Chalk can hold solution features, so unexplained settlement, a failing soakaway or a sudden dip in the ground is investigated rather than dismissed.
Is there flood risk in the conservation areas?
Not from rivers or the sea on the planning map: the Flood Map for Planning puts neither area in Flood Zone 2 or 3. Surface water is a separate layer on the long-term flood risk service, and that is the check to run for an individual address.
What sort of homes surround the two areas?
Across the three surrounding LSOAs, VOA figures for 2025 show 39.8% of about 2,590 dwellings built in 1919-1939 and 23.6% since 2000. Flats make up 36.3%, with semi-detached, detached and terraced houses sharing most of the rest.
What should I mention when asking about an interwar house?
The address, what prompted the question, and any record of extensions, loft conversions, underpinning or drainage repairs. If the house is in either conservation area or near Priory Gardens, mention any planning advice already received, since it affects which changes are realistic.
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