Good idea sealing the osb roof with bitumin paint and using the flashband to seal the joints.Great tips.Dont forget to drill through the tee hinges in a couple of places and bolt through with 6mm coach bolts for extra security, also the hasp.
Almost always invest in better roof felt than supplied if you can. Can get stuff with a 25 year guarantee for not much more than the big store stuff. Worth the extra investment in the long run.
