I'm trying to find out what insulation material is best for a typical flat roof here in Malta.
I have a quote for 50mm polystyrene sheets, and I'm told this is a lot cheaper than having the foam process carried out - but I've still to work out the difference in terms of thermal insulation, which is key for us - we don't want to cook in summer :-)
If anyone has experience with this, I'd love to hear about it.