Hi

In my 1909 house , the downstairs toilet closet was "semi outside" that is, it was within the rear wall of the house but opened onto a short covered walkway and then to the outside rear of the house.

I decommissioned the toilet and small sink some years ago and the closet has since been a "glory hole." There is just the vertical ceramic soil pipe just above floor level remaining of the toilet system.
I did , again some years ago ,purchase a proper plastic two piece, screw on, blank to seal the soil pipe. However the plastic collar part was just a little too big for the diameter of the ceramic pipe. Therefore so far, the soil pipe has been blanked off by just a plastic bag with newspaper in it being gently wedged in the pipe mouth. There have been no problems with odour or other
nasty things.

I now intend to incorporate this closet area within the Kitchen area.
This will involve internal wall demolition but before this I need to dig out and raise the floor level of the closet and walkway up to the higher level of the kitchen floor with DPC,insulation,concrete etc.

So this will permanently cover the soil outlet and this is issue.

In principle , is this ok ?
& How ?
just concrete over ?
Try to get another size plastic cover ? or maybe grind out the ceramic pipe a little to to get this one to fit . & concrete over the screw on cap.
Of course the screw on nature of the cap suggests that this is really intended for occasional access .
Any thoughts or suggestions gratefully received.


Thanks

Moggs