I have filled with kingspan between some studding, (on the inside of a stone wall with lime mortar) and foamed most of the gaps with pink drywall foam.
Now it needs a vapour barrier before I put the plywood back, to stop condensation in the wall from warm wet indoors air drifting outwards.
Someone suggested using aluminium kitchen foil for this: someone said plastic sheeting is not vapour-proof.
What sort of glue will stick the foil to the wood and kingspan?
Any better ideas andor advice please?
[g]