Ceiling membrane

[LaChab]

Hi,

 

I'd really welcome some thoughts and advice about selecting an air tight membrane for the upper floor ceiling.

 

I've done loads of searches and read lots of topics, but I can't really find an answer.

 

It's an ICF house, with a ventilated cold roof built with attic trusses.

My plan is to have some PIR hung under the attic floor joists to give a continuous layer, then possibly some more PIR and/or rockwool in between the joists.

 

But I've no idea what to use for the membrane. I'm sure it needs to be airtight, but would just polythene sheet be good, or do I need something more technical?

And do I put it between the plasterboard ceiling and the PIR, or above the PIR and under the truss joists?  Or fit both?

And any recomendations for what adhesive to use for bonding the membrane to the EPS walls would be great.

 

Thanks for reading,

[jayc89]

Plenty of people have used Pro Clima Intello Plus. I used DuPont Tyvek AirGuard.

[LaChab]

@jayc89 Thanks for the reference to Airguard. I'll have a look. I'm sure Intello is good, but as I've got a cold roof I'm not sure that I need variable membrane, just airtight. Hoping for advice!

[Eric]

@LaChab if you decide to use DuPont Tyvek Airguard I have a new roll leftover for sale.

[Nickfromwales]

5 minutes ago, Eric said:

@LaChab if you decide to use DuPont Tyvek Airguard I have a new roll leftover for sale.

Whack them on the marketplace here, they'll soon be gone