As i understand it, when fitting celotex foil backed boards between rafters ready for plasterboarding over to make a ceiling, I need to seal any gaps with something. I have a large amount of black duct tape - is that OK or should it be foil tape?
Also, with the celotex being foiled on both sides, do I still need a vapour barrier between them and the plasterboards?
Also, with the celotex being foiled on both sides, do I still need a vapour barrier between them and the plasterboards?