Electrics and gas
The stopcock under the sink would not turn. Is that a failed plumbing test, or a record that the supply could not be isolated?
Not a failed plumbing test. The stopcock under the sink would not turn, so the record is that the supply could not be isolated from there. A home survey does not pressure-test the plumbing. Finding this valve seized is an observation about that stopcock, not a verdict on every pipe in the house. It does not prove a leak and it does not prove the main is sound. Ask a plumber to free or replace the valve with the seller's agreement. Do not force the handle yourself on a viewing.
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?
Isolation means being able to shut the water off. A stopcock that will not turn means the surveyor could not do that at the point they tried. It is not a pressure trial, a drain-down, or a check of every joint. A home survey does not certify the plumbing. One stiff valve under the sink does not rate the whole cold-water installation, and it does not say the pipes above it have failed.
Ask the seller whether another stop exists, in a pavement chamber or a cupboard that was not opened, and ask a plumber what it would take to free this one without snapping it. Do not lean on the handle at a second viewing. If your solicitor needs to know that indoor isolation was not demonstrated, give them the survey sentence. Freeing the valve later is ordinary plumbing, not a rewrite of a test the survey never claimed to pass or fail.
What should you ask your surveyor?
- Where was the stopcock, and how far would the handle actually move?
- Did you find any other indoor valve that did isolate a branch?
- Was the spindle painted in, leaking at the gland, or simply stiff?
What are the typical next steps?
- Read the note as a seized stopcock, not a failed pressure test.
- Ask whether another stop exists outside or elsewhere indoors.
- Do not force the handle on a viewing.
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
If you cannot isolate the water at that valve, must you withdraw?
No. A stopcock that would not turn is not an order to leave the purchase. It means isolation was not shown there. Ask a plumber before you decide anything wider.
Does a seized stopcock mean the pipes are lead?
No. The valve and the pipe material are different facts. A handle that would not turn does not show whether the buried supply or the indoor tubes are lead.