Old Gully Under Floor

[j0nb0y]

My friend has been getting sewerage smells under her kitchen cabinets. I have taken the floor boards up and found an old gully grid under the floor from before the kitchen extension was built. I am assuming this is the source of the smell. Is it ok to concrete over it and stop the smells??? Also we have now found she has rats under her floor too, I am assuming they are getting in through this gully too? Although the cast iron gully grid is still in tact. Any advice, much appreciated.

[Canary42]

Just make sure it is an old gully no longer in use - it may become active in flood conditions otherwise.

[KARL]

Covering it with a sheet or plate of some sort might be the better approach, assuming that could then be thoroughly sealed. The sheet/plate can also be weighed down with mortar if desired/appropriate. I am assuming nothing from above this drain point, i.e. within the kitchen, drains to it (seems not as it is enclosed underneath the cabinets). Clearly Canary is correct that if the kitchen is flooded then it will no longer drain to this point and if there is back-flow through the sewer then the seal may be lifted away if the flood is severe enough. Rats inhabit most/all sewers and are capable of passing through very narrow passages, including (especially as juveniles) through some gratings.

[The Builder]

Very bad practice to just leave a gully like that. In this weather especially, it will dry up, leaving you with no water trap, hence the smell.

Best practice would be to remove the gully and fit a stop-end to the pipe. I guess this would be quite disruptive, so sealing it off is the next option.

Actually, a better job would be to trace where the pipe runs, then cut and seal it there. Of course, you really would have to be sure that there are no other connections first.