Subsidence risk in Birmingham, district by district
Across the 43 Birmingham postcode districts with a guide, the British Geological Survey rates clay shrink-swell, the usual cause of subsidence, as low at all 396 sampled postcodes.
Old non-coal mine workings are a moderate or significant hazard near 13 of the 396 postcodes we checked (in B20, B21 and B42). Coal mining isn't included: your solicitor orders that search separately.
From British Geological Survey GeoSure and mining hazard grids, checked at the sampled postcodes of each district guide in October 2026. Facts with their sources, not a rating: a district with nothing found isn't safe, and one with findings isn't unsafe. The maps describe the ground, not any home.
Check a postcode in Birmingham
Free, from the British Geological Survey. No account needed. Coal mining isn't included.
District by district
Sampled: British Geological Survey ratings around 7 to 9 postcodes in each district
| District | Clay shrink-swell | Other ground hazards | Non-coal mining |
|---|---|---|---|
| B1 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B2 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B3 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B4 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B5 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B6 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B7 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B8 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B9 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B10 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B11 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B12 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B13 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B14 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B15 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B16 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B17 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B18 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B19 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B20 | Low at all 8 postcodes | None moderate or significant | Moderate or significant near 5 of 8 |
| B21 | Low at all 8 postcodes | None moderate or significant | Moderate or significant near 6 of 8 |
| B23 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B24 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B25 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B26 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B27 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B28 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B29 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B30 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B31 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B32 | Low at all 8 postcodes | landslides: moderate near 8 of 8 | Low or none at all 8 |
| B33 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B34 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B35 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B38 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B42 | Low at all 8 postcodes | None moderate or significant | Moderate or significant near 2 of 8 |
| B44 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B45 | Low at all 8 postcodes | landslides: moderate near 8 of 8 | Low or none at all 8 |
| B72 | Low at all 12 postcodes | None moderate or significant | Low or none at all 12 |
| B73 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B74 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B75 | Low at all 8 postcodes | None moderate or significant | Low or none at all 8 |
| B76 | Low at all 8 postcodes | compressible ground: significant near 1 of 8; landslides: moderate near 1 of 8 | Low or none at all 8 |
Each district guide checks 7 to 9 postcodes spread across the district. "2 of 8 postcodes" means the finding was at two of those centres, not at a quarter of homes. Open a district for its own guide, with every postcode listed.
What it means when you buy in Birmingham
Check the ground around it, then the house itself:
- British Geological Survey ratings for shrink-swell clay, landslides, compressible ground, collapsible deposits, dissolution and running sand.
- Whether the house has had a subsidence claim or been underpinned: ask the seller.
- Cracks, sticking doors and windows, and trees close to the walls: ask your surveyor.
- In coal mining areas, your conveyancer can order a separate coal mining report.
Subsidence can be expensive to put right and can make a home harder to insure. A past claim stays on the record and usually has to be declared.
Clay is common under many towns and most homes on it never have a problem. Knowing the ground helps you decide which survey to get and what to ask your surveyor to look at.
Questions to ask about a home in Birmingham
- Has the house had subsidence, or an insurance claim for it?
- Has it been underpinned, and is there a certificate of structural adequacy?
- Are there large trees close to the house, and whose are they?
- Is the area a former coalfield, and has a mining search been done?
The full report checks the house itself, not the postcode, and ties each question to what it found. See an example report.