Advice re lean-to please

whitesatin

My house (built in the early 60s) is next to a much older property. Victorian I think. When we bought it, there was a lean to built between our house (garage wall) to next door. It is difficult to see if it is actually joined but there are certainly some long pieces of wood attached to their wall. The roof used to leak quite badly so we had it replaced (actually by the neighbour who was a builder) using better quality polycarbonate sheeting. We use the area for a variety of storage, including paper, fabric etc. Anyway, the rain seems to still be getting into it which resulted in having to throw items away. I am not sure what my options are really. It is a useful, if not permanent, structure and I would really like to try to make it more weatherproof. There are bricks to the back (garden end) of it, with a door, and the front wall has been bricked in when the front driveway was renewed. I think there used to be side access but there no longer is on that side. I like having the light polycarbonate lets through as I use it to bring plants on in Spring, like a greenhouse, up on surfaces, off the concrete floor, so I would prefer to keep as much light as possible. Knocking it down is not really an option as it would be a shame to lose the storage but I would welcome any ideas, thanks.

wrightk

Only suggestion i can think of is to get out there and get a helper to sprinkle the top of it with a hose and try to locate where water is coming in (most probably on the wall side)
Depending on how severe the leak is you could install some pvc flashing to divert any rainwater away or for minor leaks apply some marine silicone

phil24_7

It could just be moisture/condensation from it being stored 'outside'.