Electrics and gas
The cold-water header tank in the loft has no lid. Does the missing lid, by itself, mean the drinking water fails a standard?
No. A missing lid on the cold-water header tank does not, by itself, mean the drinking water fails a standard. The survey has recorded what it saw in the loft: a tank with no cover. That is an observation about the cistern, not a water-quality prosecution and not a rating of the whole cold-water system. The survey did not sample the water and it does not set a drinking-water limit. Ask a plumber about a proper cover. Do not treat the open top as a failed laboratory result.
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?
A header tank stores cold water that feeds a vented cylinder or the cold taps. A lid keeps debris and light off that stored water. Seeing no lid means the cover was absent on the day. It does not mean a sample was taken, and it does not mean the mains supply has failed any standard. The buried pipe, the rising main and the kitchen tap are different parts of the story. One missing cover is not a verdict on all of them.
Have a proper cistern lid fitted once you own the house, or sooner if the seller agrees in writing. Until then, do not climb into the loft and improvise a board. Tell your solicitor the survey recorded no lid, so the sentence is not later described as a water test. If you have a separate concern about the incoming supply, that belongs with the water company. Replacing a cover does not rewrite what the survey simply found missing.
What should you ask your surveyor?
- Did you see the header tank fully, and was the lid absent rather than only displaced?
- What did the tank appear to feed, if the pipework in the loft made that clear?
- Was there debris or staining in the open tank, or only the missing cover?
What are the typical next steps?
- Treat the missing lid as an observation, not a failed drinking-water test.
- Ask a plumber for a proper cover once you are entitled to have one fitted.
- Do not describe the open tank as a prosecution of the water supply.
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 an open header tank mean you should not drink from the kitchen tap?
No. The survey did not test the kitchen tap, and a missing lid is not a result for the water in the glass. The incoming main and the loft tank are not the same length of pipe.
Should you drop a board on the tank during the viewing?
No. Do not alter the seller's cistern on a viewing. A borrowed board is not a proper lid, and it would not turn the survey sentence into a pass.