I know that you are not a great fan of installing skylights in a bathroom but our bathroom is in the middle of the house and a skylight was the only way to get light in. Our house, in the Ottawa, Ontario area, is 10 years old and the opening for the skylight is about 20" wide and between 5' and 7'. The skylight faces West and we can't keep paint on it. We are planning to install an exhaust fan near the top of the opening to eliminate the heat and condensation build up. Is there a joint compound that will perform better in high heat/condensation. Secondly for the exhaust fan, can I put a thermostat in parallel with the wall switch so that I can turn the fan on manually when necessary but it will also go on when the heat gets too high.
Answer:
You might be better off just to install a 200 or 300 CFM squirrel cage type bathroom exhaust fan on each side of the skylight well walls. To get rid of the noise, the motor and fan could be quite dislocated from the well somewhere in the attic and still be very effective. I would then certainly install the humidistat the way you suggest.
