Spray foam and IAQ, possible upgrades
I live in zone 2b and am considering doing a bunch of upgrades to my home or moving and building a new one. Current house was built in 2010:
Single story
Medium/High pitch roof
Shingle roof
Hvac and ducts in vented attic
Blow in insulation in attic
Here is my current plan and just wanted to get any input/advice that anyone has
Remove blow in from the perimeter of attic (leaving in middle as I’m going to deck some more for storage and want the blow in for noise reduction)
Open cell spray foam
Install exhaust fan to put attic under negative pressure
Put dehumidifier in attic to regulate humidity
Put in new hvac system that is properly sized for my new setup
Install exhaust fan in garage as well
I’m planning to install solar panels as well after I see what my new energy requirements will be
Where are the flaws/what am I missing?
Thanks for any input
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Replies
Run BeOpt simulation to validate your payback (if any). You will be... surprised.
T. Davis,
You haven't really described your plans very well. You mention "open-cell spray foam," but you don't tell use where you want to install it.
Will the open-cell spray foam be installed just near the eaves?
Will the open-cell spray foam be installed against the exposed drywall ceiling?
Will the open-cell spray foam be installed on the underside of the roof sheathing?
How thick will this open-cell spray foam be?
It's a bad idea to install an attic fan to put your attic at negative pressure with respect to the house. This article explains why: Fans in the Attic: Do They Help or Do They Hurt?
Foam is lousy for noise attenuation as compared to Roxul or cellulose.