You might try caulking around the fan where it meets the ceiling. How about
getting some aluminum duct tape and taping over the holes inside the fan
housing? I bet the fan and motor comes out. Tape any seam.

You might try adding an inline damper such as that offered for clothes
dryer. Make sure the fan have enough CFM's to open all dampers.

Regardless of what you do, when it is windy the dampers will open and you
will lose heat. It is a matter of low pressure outside and higher pressure
inside.

"HeyBub" wrote in message
...
Donna wrote:
Our bathroom has a ceiling fan/light combination that lets in one
hell of a draft. During our saga about the leaking bathroom roof
(resolved, it seems, finally), I got a look at the construction, and
the exhaust fan shunts the air through something that looks a bit
like a dryer hose, to a circular exterior port on the house. That
port is hooded, and there is some kind of apparently useless circular
"flap" that does very little to keep cold (!!! it was 20 below last
night) air out of the bathroom.
If you wizards can suggest a way to solve this, other than only
showering in the summer, I would be eternally grateful.

Donna

Got a spare towel to stuff int he hole?