Drywall adhesive - waterproof?

[jimjamyahauk]

Hi,

I'm about to dot and dab some laminated insulation plasterboards (Kingspan K17) to the internal face of an external wall.

There will be a fire-stop line of adhesive at the top and around the edges to also reduce interstitial condensation risk. Once dry a few mechanical nailable plugs will also be added to secure for fire regs.

I've been recommended that I use a waterproof drywall adhesive as this is an external wall in case any passing penetrating damp occurs in the future.

Had a look around and can't seem to find any waterproof drywall adhesive or additives that seem suitable.

Does anyone have some advice on this - or should I just use standard drywall adhesive: http://www.british-gypsum.com/produ...roc_accessories/gyproc_dri-wall_adhesive.aspx

Thanks,

James.