Quick insulation question

[MIHP]

Quick question chaps:

Insulating man shed for winter. Is it

insulation (jabwall) / polythene sheet - water proof vapour barrier / cladding ?

or

Polythene vapour barrier / insualtion / cladding ?

Thanks guys

 

[EddieM]

if the insulation is permeable vapour barrier on the warm side (interior)

 

[MIHP]

The insulation is jabwell which is 'moisture resistant'.

I am going to need to add battens to the pitched roof to enable me attach the cladding after I've put jabwell in the roof.

The only way I can think to do it is to drill externally through the roof felt to attach the batons. I am obviously concerned about water getting in. Do you reckon I could get away with applying some sort of sealant over and around the screw head?

Or can you think of another way?

I'd appreciate thoughts guys

thanks.