Re underlay… but you’ll also get away without it. We just laid some similar stuff in - what will be - the bike/turbo room, and went without.
There was a small divot where we’ve taken out a toilet and the waste - we used some left over fibreboard (from the wood floor in the rest of the flat) to fill that divot.
If the Corka stuff is as easy as what we have, you’ll be done in a morning in a nice big room like that. Not much cutting.
Re underlay… but you’ll also get away without it. We just laid some similar stuff in - what will be - the bike/turbo room, and went without.
There was a small divot where we’ve taken out a toilet and the waste - we used some left over fibreboard (from the wood floor in the rest of the flat) to fill that divot.
If the Corka stuff is as easy as what we have, you’ll be done in a morning in a nice big room like that. Not much cutting.
Good luck!