membrane behind hardie or not

[mache]

Hi if you have Hardie board on studs and are tanking.the area do you also put a membrane between the Hardie boards and studding as a precaution as well. Instinct tells me membrane not required but I think Hardie recommend a membrane in wet area as long term protection of studs in case of vapour penetration.
Your thoughts please, thanks.

 

[One Day]

My thoughts - scrap the Hardi and use a proper "waterproof" board like Kerdi board or Wedi and tape the seams / screw heads.

Save time+money+headaches.

 

[mache]

Thanks for input impish, bit far down the road to change now as boards need to go up today. Your post will help others searching threads in the future I'm sure.

 

[Spud]

If hardie recommend it then I would install a membrane

 

[The D]

are you looking at UK or USA spec

 

[mache]

are you looking at UK or USA spec

Good point, just looked again from Hardie UK site at installation instructions and just says see applicable building regs re vapour barrier requirements. Maybe I had picked something up from a USA you tube video which made me think it was required. Looking with fresh eyes seems OK with just tanking. Thanks.

 

[Perry]

yes you should tank Hardie as its not waterproof only water resistant.

 

[mache]

yes you should tank Hardie as its not waterproof only water resistant.

Thanks pjc, definitely tanking but had got in my head that maybe a vapour barrier was required between boards and studding.

 

[Perry]

Thanks pjc, definitely tanking but had got in my head that maybe a vapour barrier was required between boards and studding.

not if you are tanking it