Does anyone know of an attic ventilation product that sit inside a window? I just bought a 3 bed ranch style that has ventilation problems.. Roof sheeting looks like its been damp and previous owner said when the seasons changed water would drip from the ceiling fans. It has a ridge vent but it doesn't appear to be allowing any air movement. The only other thing up there is a long window on the South side. I'm imagining something that would fit kind of like a window a/c unit where I could just open the window, set it up and close the window back down on top of it to hold it in place. Any suggestions? There is an outlet near the window so I'm thinking the ideal product would be a temperature sensing vent fan. It has older asphalt shingles that I'm hoping will last another 3-5 years before I put stone-coated steel on. Thanks!
It sounds like what you have is condensation that's probably stemming from an underlying insulation problem. Adding space for air flow may be part of a solution, but you'll probably need to go a lot further and dig into what's causing the condensation in the first place. Badly installed or poorly-planned insulation can cause condensation issues, especially in places where snow and frost are part of life. Unfortunately, it's unlikely that there's going to be a simple bandaid solution.
What you need to do is get someone out there who understands the building science behind insulation strategies and can help troubleshoot the actual reason for the condensation to be happening.