Property risks
Flood & environment — explained
Flood risk, radon, mining and ground stability — what affects lending, insurance and safety, and how to check each one.
In OfferCheck this is the Flood & Environment component (20% of the PropertyCheck IQ), sourced from Environment Agency · UKHSA radon · Mining Remediation Authority · BGS.
Check a property’s risks →Questions buyers ask
Can I get a mortgage on a high flood-risk property?
Rarely declined on flood alone, but buildings insurance (and sometimes a flood report) will be required.
Has this house ever flooded?
Risk ≠ history; flooding history comes from the TA6 form, insurer claims, or local knowledge — not the EA rating.
What's the difference between Flood Zone 3 and "high risk"?
Flood Zones (1/2/3) are the planning tool; buyers see High/Medium/Low/Very low from NaFRA2.
Can I insure a home at flood risk?
Usually yes via Flood Re for eligible homes — but Flood Re excludes homes built after 2009.
Why is surface-water risk high when I'm not near a river?
Surface water is rainfall/drainage-driven and independent of rivers.
There are flood defences — am I safe?
Defences reduce but don't remove risk; insurers and the rating already factor known defences in.
Is radon a reason not to buy?
Almost never — remediation (ventilation/sump) is usually cheap and effective.
How do I find my home's radon level?
A 3-month UKHSA-validated test kit (~£50); maps only give a probability.
What's the safe radon level?
UK Action Level 200 Bq/m³, target 100 Bq/m³.
Can I get a mortgage over old coal workings?
Almost always; a CON29M mining search is routine in coalfields.
Could the house collapse into a mine?
Extremely unlikely; the flag matters only with recorded shallow workings/shafts near the plot.
Who pays for mining subsidence?
For coal, the Mining Remediation Authority (Coal Mining Subsidence Act 1991); Cheshire has a brine scheme.
Do I need a search if it's not a coal area?
Yes if tin/salt/limestone — those need their own mineral search.
Is this house subsiding?
Area data shows potential; cracks/movement need a structural engineer.
Are big trees near the house a problem?
On clay, yes enough to get advice — but you may not be able to remove them (TPO/conservation), and fast removal risks heave.
Can I insure a house on clay?
Usually yes; past subsidence must be declared and limits insurer choice.
Should I buy a house with past subsidence?
Not fatal if fully remediated and documented, but it narrows lender/insurer options.