Toilet bowl height and bore hole in wall issue

[Rachel G]

If your joists are @ 300mm centres then 18mm should be fine but best to check (not the gap between them, rather centre of one joist to the centre of the next) ... check how deep they are too, not just the width.

Oh dear, so they are actually 40mm centre to centre, 48mm wide and 190mm deep. The previous ply was 19mm.

I have another potential issue now too (!) I know I should leave a bit of a gap at the bottom of the plasterboard on the stud partition wall so it doesn't get damp if the floor does. By the time I've got all the layers on the floor (underfloor heating, tiles etc) I'll be halfway up the 2x4 I used for the sole plate. If I then leave a gap, the insulation in the middle of the wall will be exposed! Or rather, not exposed but only covered by the skirting board. What to do??

 

[denso13]

so they are actually 40mm centre to centre

400mm is ok for 18mm.

I should leave a bit of a gap at the bottom of the plasterboard on the stud partition wall so it doesn't get damp if the floor does

Are you tiling the wall as well? If so, it'll be ok with no gap, it should be all sealed by the tiles anyway.

 

[Madrab]

Or just use a 9mm strip of any wood fill it in.