Greenhouses, Sheds and Sun Rooms - Sunroom leaking

We are having problems with our sunroom roof leaking when it rains. We've lived here for a year and a half and it steadily gets worse to the point we have a long puddle running across the floor of our sunroom when it rains. The ceiling is made of metal panels and it leaks from one of the cracks where two are fit together. We've been battling carpenter ants in the roof panels as well, so I don't know if that is adding to the problem or not. Is there a low-cost way we can fix this ourselves?

I would suspect that the leak would either be occuring at the highest point of the roof, where it attaches to the house, or at the end of that panel you mentioned and running around the end and back toward the house. Hard to say without seeing it or knowing exactly where the leak is. Unless you can figure out exactly where the leak is originating, all you can do is keep trying different things to fix it until one of them finally works. One product I like using can be found at: http://www.doityourself.com/store/6696132.htm It can be applied with a disposable foam brush, or you can just pour it on, it's self-leveling. Its great for fixing leaks on metal roofs.