Drainage and septic tanks
The interceptor stopper is missing and the chamber smells. What fresh-air inlet question is that, and what camera survey has it not replaced?
The missing stopper raises a fresh-air inlet question: whether air and smell are still meant to move at the inlet, or are simply pouring through the open interceptor. It has not replaced a camera survey. The chamber smells and the stopper is gone, which the survey can see. Nobody ran a camera along the drain. A smell and an empty socket are not a picture of the pipe, and they do not show whether the fresh-air inlet still works.
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?
An interceptor sits between the house drain and the sewer, with a stopper and, traditionally, a fresh-air inlet so the house side can ventilate. Without the stopper, sewer air can take the wrong route and the inlet may no longer be doing the job it was built for. That is the question the smell poses. It is not a map of cracks, roots or a collapsed pipe. A camera survey is the visit that looks along the bore. This inspection did not commission one.
Ask a drainage contractor about the missing stopper and the fresh-air inlet as a ventilation and fitting question, and ask separately if a camera is still warranted. Tell the solicitor the survey saw a smell and a missing stopper only. Do not write to a lender that the drain was camera-surveyed. The home survey has not replaced that test, and replacing a stopper is not the same job as filming the run.
What should you ask your surveyor?
- What fresh-air inlet question does the missing stopper leave open?
- Which camera survey has this chamber note not replaced?
- Did you see the smell and the empty socket, and nothing further along the pipe?
What are the typical next steps?
- Treat the smell as a fresh-air inlet and stopper question.
- Do not call the chamber note a camera survey.
- Ask a drainage contractor if the stopper and the inlet need a separate look.
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 the smell fades with the cover on, has the pipe been filmed?
No. A cover that damps a smell changes the air at the chamber. It does not film the drain and it does not answer whether the fresh-air inlet still works. The missing stopper is still missing. The survey has not replaced a camera survey with a lid that happens to seat.
Does a new plastic stopper, if fitted later, clear the run?
A new stopper would close the socket the survey found empty. It would not camera the pipe and would not, by itself, prove the fresh-air inlet is correctly arranged. The inspection has not done either job. Fitting a cap later is a repair someone else would make, not a survey already completed.