bathroom moisture / ventilation problem

syd barrett

Hi folks, need some advice please. We have one very small bathroom that has a tremendous moisture problem. A long shower translates into water literally running down the walls, brand new light fixtures rusting within a few months, etc. It's bad. And this bathroom is next to my 14 year old son's bedroom, so he uses it all the time...mostly for 30 minute showers.

We thought about withholding food and shelter until he moved in with the neighbors, but that didn't seem fair to them. So we're considering upgrading the ventilation fan to remove more moisture. At first I thought this would be simple - just go buy the biggest baddest fan I can find at Lowes or Home Depot and install it.

But now I'm doing a little research and I see all of these calculations involving CFM, Static Pressure, Equivalent Duct Lengths, etc. My question is - is this really necessary? Do I really need to do the math and go up in the attic to investigate the exhaust pipe and all of that crap? Or will it be OK to just use a bigass fan that's probably overkill for this tiny little 9x5 bathroom?

Thanks in advance for any comments and/or observations.

mattedfred

maybe just go buy the strongest residential fan for sale at HD, make sure the ducting isn't clogged etc and install a timer switch with a 60 minute selection.