Coal Mining Search by Postcode — Do You Need a CON29M?

The question most buyers actually have isn't "is there coal under here" — it's "do I need to pay for a CON29M coal mining search, and what happens if it flags something?" This check screens any UK postcode against coalfield referral areas using official Mining Remediation Authority (formerly Coal Authority) data, so you know up front whether a formal CON29M is likely to be required. Then it explains the rest: what a CON29M actually covers, how mine-entry proximity and subsidence claims work, and why lenders insist on the report. Around 25% of homes in England, Scotland and Wales sit on coalfield ground. The £24.99 Complete report includes the coalfield screen for a specific address, alongside flood, EPC and more — 15+ checks from official sources.

No signup. Postcode-area screen of Mining Remediation Authority (formerly the Coal Authority) open data, published under the Open Government Licence.

This check runs on screen, no signup. The full property report is £9.99 Lite / £24.99 Complete — one report, one price, no subscription.

Do you actually need a coal mining search?

If you're buying a home in a former coalfield, a CON29M coal mining search is almost certainly coming — not because you asked for it, but because your lender requires it and your conveyancer orders it as standard. This page exists to answer the question buyers really have: am I in coalfield territory, will I need the search, and what happens if it flags something? Enter a postcode above to screen against the official Mining Remediation Authority (the body that took over the Coal Authority's functions) coalfield referral areas, then read on for what the formal search covers and how to act on it.

What a CON29M coal mining search covers

The CON29M (often written Con29M) is the Law Society's standard coal mining and brine search. For the specific property it answers a fixed set of questions:

  • Underground workings — whether the property is within the likely zone of influence of past, present or future recorded coal mining.
  • Mine entries — the presence and distance of shafts and adits, the highest-risk surface features in any coalfield.
  • Surface hazards and gas — whether the site is in a surface-hazard zone or an area of potential mine-gas emission.
  • Subsidence claims — any recorded coal-mining subsidence damage claim or notice affecting the property.
  • Past remediation — works the Authority has previously carried out, such as shaft capping or grouting.
  • Development high risk areas — whether the site falls in a zone that would require a full Coal Mining Risk Assessment for new development.

It is a desktop legal search, not a structural survey — but it is the document lenders and solicitors rely on, and it costs only around £30–£50.

Mine entries — the feature that drives the risk

The single most important thing a coal mining search reports is proximity to mine entries — the shafts and adits that gave historic access to the workings. A poorly capped, displaced or unrecorded shaft can collapse and open a void at the surface, which is why a property sitting very close to a recorded entry (commonly within around 20 metres) can trigger a referral for a more detailed assessment. Close mine-entry proximity can affect insurability and, in some cases, require ground investigation or grouting before a lender will release funds. If your search flags a nearby entry, that is the line to take to your surveyor first.

Coal-mining subsidence claims and your rights

Where past workings cause a building to subside, the Coal Mining Subsidence Act 1991 gives owners a route to have damage put right, administered by the Mining Remediation Authority — which can fund repair or preventive works. The CON29M discloses whether any subsidence damage claim has previously been made for the property. A history of claims is a genuine material fact: it confirms known ground movement, can affect your buildings insurance, and is precisely the kind of finding your solicitor will raise before exchange. A clean record is reassuring; a claims history is something to price in or investigate.

Why lenders insist on it — and what an adverse search means

Mortgage lenders lend against the property as security, and unstable mine workings threaten that security. Under the Council of Mortgage Lenders' Handbook and the Law Society's coal-mining guidance, the lender's solicitor must obtain a coal mining search for any property in a coalfield and act on adverse findings. In practice an adverse CON29M can require remediation, a specialist ground report, or occasionally stop the lender proceeding altogether — which is why the search is effectively mandatory in mining areas, regardless of the buyer's own appetite for detail. Knowing in advance that you're in coalfield territory means none of this catches you out late in the transaction.

Coalfield Britain — where the risk concentrates

About a quarter of homes in England, Scotland and Wales sit on coalfield ground. The main belts are South Wales, Yorkshire, Nottinghamshire and Derbyshire, the North East (Durham and Northumberland), Lancashire, the Midlands, and the central belt of Scotland. Being "in a coalfield" does not automatically mean high risk — only a subset of coalfield land falls into the development high risk or referral zones that trigger extra assessment. This postcode screen tells you which side of that line a property sits on, before you pay for searches or commit to an offer.

Coal mining vs general ground stability

A coal mining search answers a specific question — risk from coal workings. It does not cover the natural ground hazards that cause most UK subsidence: shrink-swell clay, landslides, compressible ground and dissolution (the mechanism behind sinkholes). Those come from British Geological Survey data. A complete underground picture needs both, which is why our wider subsidence check by postcode screens BGS GeoSure and coalfield data together. Use this page for the coal-mining and CON29M question specifically, and the ground-stability check for the natural-ground side.

From a postcode screen to an address report

This check works at postcode level — enough to tell you whether a CON29M is likely in play. When you've shortlisted a property, the Complete report (£24.99) runs the coalfield screen for the specific address, alongside flood risk, the EPC, ground stability, crime and the rest of its 15+ official-source checks — the underground and environmental picture that decides whether a home survives due diligence. The formal CON29M from your conveyancer remains the legal document of record; this tells you to expect it.

Sources: Mining Remediation Authority (formerly the Coal Authority) coalfield and development-risk data; CON29M is the Law Society's standard coal mining and brine search. Contains public sector information licensed under the Open Government Licence v3.0. Coverage: the coalfields of England, Scotland and Wales.

Frequently asked questions

You need one if the property sits within a coalfield 'development high risk' or referral area — and your conveyancer will almost always order it for any property in a coalfield, because mortgage lenders require it under the Law Society's guidance. The CON29M (Con29M) is the Law Society's standard coal mining and brine search. If a postcode is well outside any coalfield, a CON29M is not needed and your solicitor will say so. This check tells you whether you're in coalfield territory before you reach that stage, so the search isn't a surprise line on your completion statement.
A CON29M report from the Mining Remediation Authority answers a fixed set of questions for the property: whether it is within the zone of influence of past, present or planned underground coal workings; the presence and proximity of mine entries (shafts and adits); any recorded coal-mining subsidence damage claims; whether the property is in a surface-hazard or gas-emission area; details of any past Coal Authority remediation; and whether the site is in a 'development high risk area' that would trigger a Coal Mining Risk Assessment for development. It is a desktop legal search, not a structural survey — but it is the document lenders and solicitors rely on.
A residential CON29M coal mining search from the Mining Remediation Authority typically costs around £30–£50, usually ordered by your conveyancer as part of the standard searches pack (which also includes local authority, water and drainage, and environmental searches). Personal-search providers offer equivalent products at similar prices. It is one of the cheaper searches and, in a coalfield, non-negotiable — lenders won't proceed without it. Use this postcode check first so you know whether it applies before you commit to a property in a mining area.
A 'mine entry' is a shaft or adit (a horizontal tunnel) giving historic access to the workings. They are the highest-risk feature in any coalfield because a poorly capped or unrecorded shaft can collapse, opening a void at the surface. The CON29M reports the distance to the nearest recorded mine entry, and a property sitting very close to one (typically within 20 metres) can trigger a referral for a more detailed Coal Mining Risk Assessment, may affect insurability, and can require ground-investigation or grouting before a lender will lend. Distance to mine entries is one of the first things a surveyor and lender look at.
If past coal workings cause your property to subside, you may have a claim under the Coal Mining Subsidence Act 1991, administered by the Mining Remediation Authority — which can fund repairs or, in some cases, the cost of preventive work. The CON29M discloses whether any subsidence damage claim has previously been made or notified for the property. A history of claims is a material fact: it signals known ground movement, can affect insurance, and is something your solicitor and surveyor will want to examine before exchange.
Because unstable mine workings can damage or destroy the security the loan is lent against. The Council of Mortgage Lenders' Handbook and the Law Society's coal-mining search guidance mean that for any property in a coalfield, the lender's solicitor must obtain a coal mining search and act on any adverse findings. An adverse CON29M can require remediation, a specialist ground report, or — occasionally — stop the lender proceeding. This is why the search is effectively mandatory in mining areas regardless of what the buyer personally wants to know.
Approximately 25% of properties in England, Scotland and Wales lie within a coalfield. The main areas are South Wales, Yorkshire, Nottinghamshire, Derbyshire, the North East (Durham and Northumberland), Lancashire, the Midlands, and the central belt of Scotland. Within those coalfields, only a subset fall into the 'development high risk' or referral zones that trigger extra assessment — which is exactly what this postcode check screens for.
No — they overlap but answer different questions. A coal mining search (CON29M) looks specifically at risks from former and present coal workings: mine entries, recorded workings, gas, and mining subsidence claims. A general ground-stability check screens natural hazards like shrink-swell clay, landslides and dissolution (sinkholes) from British Geological Survey data. A complete picture needs both, which is why our wider ground check screens BGS GeoSure and coalfield data together — see the subsidence check by postcode for the natural-ground side.

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