sealing celotex with tape

[WabbitPoo]

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?

 

[noseall]

We always use the (recommended) foil tape. We also use foam and silicon on larger gaps. We then fix foil back plasterboards to complete the vapour barrier.

Can't say about the duct tape.

 

[drpepe]

We always use the (recommended) foil tape. We also use foam and silicon on larger gaps. We then fix foil back plasterboards to complete the vapour barrier.

Can't say about the duct tape.

I've been using foil tape for this purpose, but I am a bit concerned that general stickiness and strength of the foil is much less than duct tape.

In tricky areas I've been doubling up with duct tape.