Remove Condensation & insulate shed
I have a colourbond garage used as a workshop and had thoughts of insulating the roof to make it more useable in the hotter and colder months. I did not install any sarking when the shed was built and I get a little bit of condensation on cold mornings. The roof is a gable with 3 purlins on each side of the roof. I was thinking of putting in a false sealing about 6 inches from roof and installing some fibreglass batts. If I do this will I get more condensation and end up with damp batts. If I install sarking, I am guessing I will still get condensation on the inside of the roof but that it will then drop onto the sarking. How is the moisture then removed from the sarking.
With sarking, do I need to purchase foil sarking or can I use a polytarp which is cheaper.
It could be that I don't understand how the sarking works.
What is the best approach.