downstairs toilet

You would need to contact your gas and electric suppliers first of all. But before all that, if it’s possible, put a chair in there and see if you can get up from it without banging your head on the ceiling or the wall opposite !! This way you’ll no whether it’s suitable before you go to the expense of moving meters etc.

First I would check to see if your drain (fowl) is near by for you to tap into. Secondly I would contact the gas/electric board, they would recommend to move these outside for smart meter reasons. Cold and hot water feed is also something to think about Mike MJC

The problem with this suggestion is that once you install the proposed toilet you would be restricting the access to the alleged gas and electric supplies, these appliances need to be free from obstruction and generally the width of a stair case would be very tight for all this to be squeezed in. My advice if you are insisting on utilising this space would be to perhaps investigate the relocation of these two appliances distribution points and free up the entire space, all be it more work it would future proof your desired new Toilet.

Quite expensive to move meters but then you need to get at least a cold water feed and then a pipe to your fowl. You could look for a saniflo system with pumps your waste away