Home extensions and improvements in former coal mining areas
Source: gov.uk (2025-11-10)

Find out what you need to do before building home extensions or making improvements to your property in areas affected by past coal mining activity.

When you need to check for coal mining risks

You must check for mining risks if your home is in a development high risk area. This includes many areas where coal was mined in the past across England, Scotland and Wales.

You can check if your property is in a high risk area, along with recorded mining information, using our free online map (https://datamine-cauk.hub.arcgis.com/).

Many home improvements in these areas do not need planning permission but could still require building regulations approval. You need to consider mining risks for both.

What home improvements are covered

This guidance applies to typical home improvements including:

house extensions

conservatories

garages and outbuildings

driveways and patios

garden structures

Understanding planning permission and building regulations

Planning permission controls what you can build and where. Building regulations ensure your building work is safe and meets technical standards.

Many extensions and home improvements can be built under permitted development rights (https://www.gov.uk/government/publications/permitted-development-rights-for-householders-technical-guidance), without planning permission, but most building work still needs building regulations approval.

Find out about when you need building regulations approval (https://www.gov.uk/building-regulations-approval).

Your building control body (either your local authority or a private approved inspector) will check that your building work complies with building regulations.

They could also ask you to demonstrate that your development is safe and stable with respect to coal mining.

The Mining Remediation Authority does not sign off or approve householder development proposals.

Your responsibilities as a homeowner

You are responsible for making sure your development is safe and stable. The Mining Remediation Authority will not carry out any investigatory or remedial safety work for you.

You should consider mining risks at the earliest stage of planning your project, ideally before submitting a planning application or building regulations application.

The Mining Remediation Authority is not consulted on householder developments as part of the planning process, but your local planning authority or building control body could still ask you to prove your development will be safe.

What coal mining risks to consider

Potential hazards include:

mine entries (old shafts and tunnels)

shallow mine workings underground

coal seam outcrops at the surface

opencast mining sites

ground fissures and break lines

mine gas

mine water

All of these features must be given appropriate consideration as part of your development proposals.

Getting a mining report

You can buy detailed information about coal mining features at your property. There are different types of report:

CON29M report: basic conveyancing information for house purchases – this should not be used to inform a coal mining risk assessment for development

consultants’ report: detailed technical information that may be useful in informing a coal mining risk assessment – this should be reviewed alongside all other appropriate information

coal mining risk assessment: professional assessment of risks to your specific development

When you need a coal mining risk assessment

Your local planning authority or building control body can request the submission of a coal mining risk assessment if they consider this necessary to inform their decision making.

A coal mining risk assessment is not the same as a mining report. It must be prepared by a qualified professional (#professional-advice) who reviews all available information for your site to determine what risk, if any, coal mining may pose to your development, and what further actions could be required.

Find out about coal mining risk assessments (https://www.gov.uk/guidance/planning-applications-coal-mining-risk-assessments).

When you need a separate permit from us

You must get a permit from the Mining Remediation Authority before starting work if your development could:

disturb or enter coal seams

affect historical coal mine workings or mine entries

This includes digging foundations or putting in new drainage that could intersect the Mining Remediation Authority’s property.

Find out about our permits and apply for one online (https://www.gov.uk/guidance/get-a-permit-to-deal-with-coal-or-coal-mines).

When you need an agreement for coal

If your building work involves removing any coal, you also need an incidental coal agreement from the Mining Remediation Authority.

Find out about our incidental coal agreements (https://www.gov.uk/government/publications/incidental-coal-agreement).

Building near mine entries

Avoid building over or close to mine entries. This includes old mine shafts and tunnel entrances. Building over or within influencing distance of a mine entry can be dangerous.

Read our policy for building over or within the influencing distance of a mine entry (https://www.gov.uk/government/publications/building-on-or-within-the-influencing-distance-of-mine-entries).

Mine gas considerations

Mine gas can be dangerous and should be assessed by a qualified specialist (#professional-advice) if there’s any risk at your site. This is especially important where there are:

coal seams or old workings nearby

mine entries or ground fissures

enclosed spaces like basements

It is prudent to undertake a gas risk assessment where a source (such as a coal seam or workings), pathway (such as a mine entry or geological faulting) and receptor (such as an occupied development) could be present.

The Mining Remediation Authority does not carry out gas risk assessments.

Getting professional advice

You should get advice from a professional who understands ground stability and mining hazards. Look for someone with qualifications in:

geology

geotechnical engineering

mining engineering

structural engineering

They should also be a member of a relevant professional body, like the Geological Society or Institution of Civil Engineers.

Further help

Find out about householder planning consent (https://www.planningportal.co.uk/planning/planning-applications/consent-types/householder-planning-consent).

For planning permission questions, contact your local planning authority (https://www.gov.uk/find-local-council).

For building regulations questions, contact your building control body (your local authority or private approved inspector).

If you discover any mining features during your work, immediately call our 24-hour hazard line: xx-xxxx-xxxx.

Customer services, mining reports and records

Mining Remediation Authority200 Lichfield LaneMansfieldNottinghamshireNG18 4RG

Email xxx@xxx.xx (mailto:xxx@xxx.xx)

Telephone xx-xxxx-xxxx