When my siding was redone they found a vent on the back wall that had been closed over that seems to be a vent for the small space between our ceiling and flat roof. Since this has been blocked off 32 years that I know of and never knew existed is this breather space necessary?
Also when I insulate my new bathroom ceiling is it necessary to leave any space between the ceiling and roof or should I fill it completely with insulation?
Replies
There are too many variables to give you a a concise answer. What's your climate like/where are you located? How old is the house? What's on the interior wall? What kind of insulation? What kind of housewrap? What kind of heat source? Do you have air conditioning? Humidity control? Whole house fan? Heat exchange ventilator? Bathroom/kitchen fans?
Check out http://buildingscience.com to get some ideas....
What Mike said.
Also,
"Since this has been blocked off 32 years that I know of and never knew existed is this breather space necessary?"
I am of the school "if it ain't broke". If you can see into the space (remove vent if necessary and there is no sign of mildew or mold, etc., then the vent isn't necessary.
HOWEVER, it is clear you are doing some remodeling and that insulating is part of the process. By making the changes you are making, you might change the way that space "works" and the new dynamic may cause the vent to be necessary.
Rich Beckman
Coming to the Fest? Don't forget pencils!!!!!!!!!!!!!