Whole House Exhaust Fan?
I am working with a client that would like to install a through roof (roof mounted) whole house exhaust fan. The house has all cathedral ceilings. It is currently poorly insulated, poorly air sealed and has a ton of glass in bad locations.
It is in Zone 5. Interior can get pretty warm inside during the summer. His previous house had a whole house fan that he thinks did a great job flushing hot air at night to “quickly” bring down the interior air temp.
We will be drastically improving the air sealing and R value of walls and roofs along with replacing all the windows over the course of a couple of phases of work. Also, will be replacing all mechanicals including central air and an HRV.
I have always been skeptical of whole fans..pressurization issues (noted on this site), leaky (air and potentially water with a through roof unit). I just don’t see the benefit of installing the fan. Am I missing something?
Thoughts?
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Replies
Chris,
Whole-house fans are actually a great way to keep a house cool during the summer, using far less energy than air conditioning. They work best in a climate with nighttime temperatures that are usually 65 degrees F or lower.
Homeowners have to remember to open downstairs windows before they go to bed. (Of course, if you live in a high-crime neighborhood that doesn't allow you to sleep with your windows open, a whole-house fan may not be a good solution.)
Choose a whole-house fan with motorized insulated shutters. The best models are those from Tamarack Technologies. These fans are designed for attic installation -- they aren't through-the-roof fans.
Thanks Martin. Any suggestions for through roof options? There is no attic space in the house.