Whole-house fan in cathedral ceiling design
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I’m building in climate zone 6B and I’m trying really hard not to put in AC. Our house is at 7000ft but we still get a few weeks of hot temperatures that are bearable during the day but are too hot for us to sleep at night. My thought was to do an air flush in the evening using a whole house fan.
We are doing cathedral ceilings and all the whole house fans I’ve seen have been installed into an attic space which we obviously don’t have. Is there another option for us? Maybe a ducted whole house fan that can be ducted up through a chase and vent directly outside. I imagine a motorized baffle on the exterior side to provide sealing during the winter months and when we are not using it.
BTW we are planning radiant floor heating so we don’t have forced air duct work except for our smaller HRV ducting.
Any suggestions on how to get a whole house air change at night with cathedral ceilings while maintaining my air barrier and thermal integrity in winter?
Steve
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Replies
Steve,
Several manufacturers produce whole-house fans for sloping insulated roofs. The fans are exposed to the weather.
Click here to see a website with many inexpensive models of whole-house exhaust fans for homes without attics.
A better option would be the TC1000-H fan from Tamarack -- a model with an automatic insulated damper that prevents heat flow and air flow when the unit is not in use.
I have this exact same question. Unfortunately, the link you point to is down. Can the Tamarack fan be installed with the damper outside of the house? Or would this work inside the chase he suggests?
Here's the tamtech manufacturer website. As for which will work, I'd probably call them. I don't think they aren't so big that they won't answer the phone and help you.
https://www.tamtech.com/product-category/whole-house-fans/
Operating skylight window?
Tom,
IMHO
Unless he buys a really expensive one and has great natural stack effect, I think a roof window would add more load during the afternoon while he's at work than it would remove during the summer evening.
Depends which way it faces. Some have internal shades that operate with remote to open both window and shade. If it is a cathedral, it should have some stack effect I would think.