Electrics and gas
What did the visit record about a cast-iron radiator, about a dripping valve, and about floorboards stained under it?
The visit recorded a cast-iron radiator, a dripping valve and floorboards stained under that drip. Those are three things that could be seen. The drip shows water was leaving the valve at the time, or that a wet valve was still wet. The stain shows water has reached the boards before. The survey did not test the heating pressure, did not probe the boards, and has not decided how far any damp timber extends. It has described a leak at a valve and a mark on the floor. It has not measured either.
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?
Cast-iron radiators often outlast the valves on their ends. A gland or a union can weep, and the water follows the pipe, the valve tail or the floor. A stain on the boards records that this has happened, not how deep the wetting goes or whether the timber is only marked. The surveyor sees the radiator, the drip and the discolouration. They do not see the underside of the board, and they do not know whether the drip is a slow weep. The note is visual.
Ask a heating engineer to repair the dripping valve and to say whether the boards need more than drying. The survey has not specified that repair and has not tested the timber. Tell the solicitor there is an active-looking drip and a stain, so the floor under the radiator is not a clear surface. If the boiler is gas, appliance work sits with a Gas Safe registered engineer. Do not lift the boards as a casual check. The depth of any damage stays outside this visit.
What should you ask your surveyor?
- Was the valve dripping during the visit, or only stained from an older weep?
- How far did the staining on the floorboards extend from the valve?
- Did the boards feel soft, or was the note colour alone?
What are the typical next steps?
- Record the radiator, the drip and the stained boards as three seen facts.
- Ask a heating engineer to deal with the leaking valve.
- Tell the solicitor the boards were not probed.
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 a cast-iron radiator have to be replaced because a valve drips?
No. The drip is at the valve, which can often be repacked or replaced while the radiator stays. The survey recorded the radiator, the drip and the stain. It did not decide the radiator has failed, and it did not test the system. Ask a heating engineer about the valve. Do not scrap the radiator on this note alone.
Is the stain proof the boards are rotten?
No. A stain shows water has been on the boards. It does not show how deep the wetting goes or whether the timber has decayed. The survey did not probe the floor and did not test the heating. The drip explains why the stain is there to be asked about. The condition of the timber under the colour stays unknown.