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If you know of any painters, an extendable and retractable painters pole is handier than a pocket on a shirt for blowing in insulation. Duct taped to the blower hose and you're GTG.
 

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going from R-19 to R-49 is not that costly. Once you have blown in that is what you need to stick with. you can have batts then cover with blown in but not the other way around.
 

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Yes, I've used that link to show convective loops are always in an attic (with passive venting), cold------ ; or hot climate; http://www.fsec.ucf.edu/en/publications/html/FSEC-PF-226-91/

Now I'm trying to convert the heat flux (using same outside temps) through the attic insulation (R-20) compared to heat through a 2x4 (R-13) exterior wall-- pp.86: http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ved=0CFMQFjAH&url=http://www.diva-portal.org/smash/get/diva2:506266/FULLTEXT01&ei=l-5-UtznJoKKiALH_oGQAQ&usg=AFQjCNGxnp4-9hrPSTKbC5n6vQVAkslv7g&bvm=bv.56146854,d.cGE&cad=rja But the wall outside temp is 5*F, with 10 W/m2 loss and the ceiling (R-20) with 32*F outside and 37 W/m2 loss, and 21*F out with 48 W/m2 loss; almost 5 times more loss and temps are warmer in attic (w. 4cm vents) than wall exterior..... anybody?

Send me a PM if you want, I'd love some help on this. Thanks, Gary

PS. the colder air (less dense) settles on the attic floor being warmed by the heat loss through the insulation to rise/exit the high vents; http://learn-science.20m.com/tmyths.htm#myth2

http://www.usatoday.com/tech/columnist/aprilholladay/2005-02-18-wonderquest_x.htm
Huh? translate to laymen's terms please
 

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With an infrared gun (Lowes has em cheap) I've seen the temp fluctuations (from air currents in my glass insulation) while aimed at the ceiling and the colder it is the wider the fluctuations.
I'm at min code here with blown R38 glass ...will upgrade to R60 I think and the link about the tyvek covering sounds like a great idea.
Great thread !
 

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With an infrared gun (Lowes has em cheap) I've seen the temp fluctuations (from air currents in my glass insulation) while aimed at the ceiling and the colder it is the wider the fluctuations.
I'm at min code here with blown R38 glass ...will upgrade to R60 I think and the link about the tyvek covering sounds like a great idea.
Great thread !
R38 is code.

There is a diminishing law of return on depths beyond that really but insulation is relatively cheap.

Tyvek does stop the wind washing but if you install cellulose, it is denser to begin with.

FYI...what you have is a Infrared Thermometer.
 
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