Radon
A radon map colour was quoted for a different postcode. Why is that colour still not a measurement taken in this house?
That colour is still not a measurement taken in this house because it belongs to a different postcode and because a map is not a reading in these rooms. UKradon maps, produced with the British Geological Survey, show indicative radon potential by area. They do not sample the air here. Quoting the colour for another postcode is the wrong area as well as the wrong kind of evidence. No radon measurement was made on this visit. The survey has not decided the level in this house.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Radon potential changes with the ground, and a neighbouring postcode can sit on a different band. Even the correct square on the map would still be an area indication, not a result from a detector in the living space. UKradon publishes an Action Level and a Target Level as benchmarks for a proper test. A borrowed colour meets neither of them. The report should not be read as if a monitor had been left in the house and analysed.
If you want a figure for this house, that is a radon test instructed separately, using this address, not a colour from another postcode. Ask the solicitor not to attach the wrong map extract to the replies as if it were a measurement. A lender may want its own requirement met by a test or the right search. This survey has not carried out that test and must not be edited into one.
What should you ask your surveyor?
- Which postcode was the map colour actually quoted for?
- What does the report say was not measured in these rooms?
- Does any sentence present the colour as a house reading?
What are the typical next steps?
- Discard the other postcode as a result for this house.
- Keep any radon test as a separate instruction.
- Do not describe the map colour as a measurement.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Does the right postcode’s colour become a house reading?
No. Even the colour for this postcode would be an area indication on the UKradon maps, not a measurement in these rooms. A different postcode is further off still. This visit did not test the air. A house reading needs its own test at this address, reported separately from the map.
Did the surveyor place a detector and then reject it?
No detector was placed. The visit did not measure radon in this house at all. Someone quoted a map colour for a different postcode, and that colour is not a result the surveyor obtained and then set aside. There is no house measurement to reinterpret. The report has not produced one.