in our utility room we have what is basically an open drain with the pipe from the sinks and washing machine going into it. there is a plastic grille on it like you have in outside drains to catch leaves and it is about the same size.
our builder reckons it is a diy job: get a rubber bung/seal of some type and fill it with concrete above. it sounds simple but I don't know the name of the product to buy.
can anyone help please?