access to a leaking pipe

[sterowley]

We've got what we believe is a leaking waste pipe, I know how to fix that if i can get access, but this house is a new build with a chipwood floor.

When we called out the insurance block he reckoned is would be cheaper to cut though the plaster board ceiling instead. Our insurance has a clause that means that they won't pay for the new ceiling and plasterwork required only pay out if the ceiling collapses .

Also we have lino flooring down which I Haven't lifted yet to take a look due to being silicon sealed around the edges and I believe glued down.
Any suggestions for the best and cleanest diy way.

 

[xr4x4]

Cut a section of the ceiling out, keep the piece or replace after, easy fill, fill and paint.

 

[IJWS15]

New build?

NHBC warranty?