You can apply Liquid Rubber straight to metal, rubber and fiberglass roofs. If the surface is shiny we highly recommend rubbing it down first to give it a good key, so the coating can stick well. Under no circumstances can it be applied to silicon, silicone should always be removed first.  

Only if on porous surfaces or anything bitumen related, we have a primer called Proflex that can be used, call 01453 872850 to order now.

Liquid rubber is easy to work with as it has a long working time, approximately 5 hours. However this means it needs about 16 hours before if it skinned over properly and rain won't distort the surface. Curing will continue unseen for many days but weather will have no affect, as it is surface dry you are good to go. 

If coating the whole roof Liquid roof covers 3.9 sqm per US Gallon. If it is just for coating the seams the you will need a much smaller amount, people often just start off with a quart for smaller areas but if doing all seams then they may buy a single gallon. 

Yes, but don't confuse with filing hollows. Self-leveling means it smooths out leaving a flat finish but only has a film of 0.5 mm so must not be used for filling hollows. 

No, only pinprick size

No, it can only be used on the outside.