Gaps in celotex floor insulation

[Rich49]

Hello all

Thought this would be pretty obvious but came home from work yesterday to find the builder has laid the floor insulation in my new extension and seems to be large gaps everywhere…. I thought the joints were supposed to be butted up tight together… some of the gaps look 20mm wide along the whole length of the board in places…. Should he replace some of them? I wouldn’t imagine expanding foam for this many gaps was a good idea, and not comfortable having screed laid where there is these gaps, surely it would affect the structure over time?
Any advice welcome, pics attached
Thanks

 

[King Billy]

It's not acceptable. If the concrete gets under the insulation, despite the membrane, the insulation could well float up.
There's no excuse for it not butting up.
I wouldn't accept it.
If it's tongue and grooved, and that prevents butting up, it's been installed wrong.
It's just a matter of flipping some of the boards.

 

[freddiemercurystwin]

Agree it's not acceptable, also once he's redone it and you've seen it or seen photo evidence check the membrane is sealed where its joined else screed may seep through the gap.

 

[noseall]

Hello all

Thought this would be pretty obvious but came home from work yesterday to find the builder has laid the floor insulation in my new extension and seems to be large gaps everywhere…. I thought the joints were supposed to be butted up tight together… some of the gaps look 20mm wide along the whole length of the board in places…. Should he replace some of them? I wouldn’t imagine expanding foam for this many gaps was a good idea, and not comfortable having screed laid where there is these gaps, surely it would affect the structure over time?
Any advice welcome, pics attached
Thanks

Poor. 3/10.