Do I need a waterproof membrane?

[RichD1]

I'm building a timber framed workshop. Construction as follows: -

70mm studs @ 400 centres
70mm Celotex between studs
9mm WBP sheath on outside
Breathable membrane paper
25mm battens
uPVC shiplap cladding

Do I need to add a polythene membrane to the face of the studs before fitting the internal wall covering?

Richard

 

[pinenot]

You could opt or duplex (foil backed) plasterboard rather than plain backed...pinenot

 

[RichD1]

I was planning on using higher density acoustic plasterboard to try and reduce the noise getting out. Does this come with a foil backing?

Richard

 

[pinenot]

Not aware of acoustic duplex boards, sorry...pinenot

 

[RichD1]

So does that mean I need to fit a waterproof membrane between studs and plasterboard?

Richard

 

[freddiemercurystwin]

Either foil backed plasterboard or a separate vapour barrier in between the studs and plasterboard eg http://www.screwfix.com/p/vapour-barrier-2-5m-x-20m/12869 The purpose of the vapour barrier is to prevent any moisture entering the insulation from the inside and condensing within the insulation.

(I don't think British Gypsum Soundbloc (acoustic plasterboard) is available with a foil facing)

 

[RichD1]

Hi Freddie, yes Soundbloc does not come foiled backed, so need a poly sheet then. Thanks guys.

Richard