As anyone who has an Ob knows leaks are one of the banes of your life.
The fact that you have to roll back or move a roof away introduces all sorts of possible entry points. I've had a few small intrusions and drips ( and one big intrusion ) and have been searching for a solution when i spotted an Ob build thread on Cloudy Nights.
The builder lived in a high rainfall area and was using a tin shed solution which he knew was not leakproof particularly at the roof overlaps which is one of my problems. His solution was to buy a Tarpaulin, one of the heavy duty silvery coloured types used to cover cars and then wrap the whole roof with it. Having recently sold on my project car I happened to have a spare tarp so applied said solution to my problem.
My roof swivels and has a wooden frame near the edge so I just stapled the tarp up underneath the eaves line then cut off the excess leaving enough to cover the junction of roof and walls. A closed door test during the day revealed I'd not only sealed every possible leak from above but created a total darkroom ! Bring on the rain !
It also creates an insulation layer which will manage inside temperatures. I possibly may lift one side and slide some sheet styrene in to improve that.
Cheap and very effective fix with extra benefits.
