# Attic Insulation - How to?



## Signal Guy (Feb 21, 2012)

Hi,

Something I’ve been confused about is attic insulation. I’m planning to insulate before next winter, but I’m not sure which way to go about it.


I live in NE Ohio. When I was young, my Dad, & I insulated our attic but installing foil-faced insulation between the eaves. This enabled us to use the attic as storage/living space. 

Now, I bought a (different) house from an estate. The fellow who used to own it had tried to insulate between the eaves, but never finished the whole attic. 
I am considering either 



A) insulating between the eaves, as the previous owner started to do, and sacrificing the R-factor.
B) laying batt insulation on the floor. To the proper depth for my climate. I would also include proper roof venting in my plan. Right now. There are vents at both ends of the attic, that have been closed off by the previous owner. If I choose option B, I would re-open the vents, and likely install roof vents.
C) insulate both in the floor, and the eaves.
 The only problem with option B is that I lose the storage space in the attic, which my wife isn’t exactly thrilled about. 


As you can see, I need input.

I have added pictures facing east, & west.


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## Windows on Wash (Aug 30, 2011)

Pictures are worth a thousand words in this case.


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## Signal Guy (Feb 21, 2012)

Windows on Wash said:


> Pictures are worth a thousand words in this case.


I understand. I'm away from home at the moment, but will post pix of the attic as soon as possible. 

Thanks


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## SPS-1 (Oct 21, 2008)

From my understanding, an attic should be either same temperature as outdoors (insulation on the floor) or same temperature as your living space (insulation on the roof). You seem to have half and half. Most people in cold climates find it a waste to try to heat their attic. From the photos, it looks about 4 feet tall. Thats not living space. What are you storing that needs to be kept warm? I would suggest the proper place for insulation is on an attic floor ( over-top of the vapor barrier and after sealing any air leaks). Hopefully you have vents under the soffits also.


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## Signal Guy (Feb 21, 2012)

Thanks for your reply. First of all, you are correct; the height is about 4', give or take. The previous owner had tried to have it both ways, with insulation in the floor, and the ceiling.

I'm leaning towards insulating the floor. To get the required R value, I'll need to lay batt insulation above the floor joists. I'm thinking that I'll need to build up the joists at least in the section that I want to use for storage. 

I don't know if I have soffit vents, or not. If I do, they aren't visible from outside. The house is a colonial, with contoured ceilings on the top floor. This makes it a bit difficult to check for soffit vents from the inside. But, I'll be spending a lot of time up there doing some re-wiring, and I will check more thoroughly.


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## joecaption (Nov 30, 2011)

It would be best to go back and tap on your name and add where you live for better advice.
http://www.energystar.gov/index.cfm?c=home_sealing.hm_improvement_insulation_table
This is what you need for insulation.
For the new insulation to work, shingles to last longer, no ice dams. You need soffit vents and a ridge vent on the roof at the peak.
Total waist of time to have insulation on those gable ends.
Far more important to have proper insulation in that attic then have that small a room for storage.
There's no coller ties keeping the roof from spreading, and now where near enough insulation in that attic no matter where you live.


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## Signal Guy (Feb 21, 2012)

joecaption said:


> It would be best to go back and tap on your name and add where you live for better advice.
> http://www.energystar.gov/index.cfm?c=home_sealing.hm_improvement_insulation_table
> This is what you need for insulation.
> For the new insulation to work, shingles to last longer, no ice dams. You need soffit vents and a ridge vent on the roof at the peak.
> ...


Thank you for the reminder. Though the means to edit the profile is likely included in the Android app, I have yet to find it. So, I hadn't gotten around to doing it. 

Guilty as charged on the collar ties. The house was built in '46, and the builders apparently didn't see a need. 
Are they important enough to consider adding? 

The insulation won't be done till after the re-wiring is completed. I have a lot of old wiring to deal with.


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## Windows on Wash (Aug 30, 2011)

I would just put off the wiring until the temps aren't quite as bad.

Here is what I would do:


Vacuum up all the old insulation to give yourself a nice clear work area.
Make all the wiring changes/updates without having to breath in the fiberglass and fuddle with it.
Air seal all the top plates, penetrations, etc prior to insulation
Make sure envelope and thermal barriers are complete, aligned, and share the same plane
Blow in cellulose to R-50+


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## Gary in WA (Mar 11, 2009)

"Guilty as charged on the collar ties. The house was built in '46, and the builders apparently didn't see a need. 
Are they important enough to consider adding? "--------

You need collar ties if you live in a high wind area, tornado alley, Gulf Coast, etc. They are to keep the rafters from spreading at the ridge board, and blowing away; "Collar ties or ridge straps to resist wind uplift shall be connected in the upper third of the _attic _space in accordance with Table R602.3(1). 

Collar ties shall be a minimum of 1-inch by 4-inch (25 mm by 102 mm) (nominal), spaced not more than 4 feet (1219 mm) on center." From: http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_8_sec002_par018.htm

Another good read on removing them: http://www.finehomebuilding.com/how-to/qa/removing-collar-ties.aspx

If you haven't seen any sign of mold, mildew, or ice dams over the years, you may not need soffit venting, especially as you are within 50 miles of a Great Lake (moisture source). Air sealing the attic, AND the crawlspace/basement to stop the "stack effect" is as important as ventilation; http://www.jlconline.com/cgi-local/...e.storefront/4d17fa04053d6e9327170a32100a05c7

Think about an unvented roof assembly and control the indoor humidity: http://www.fpl.fs.fed.us/documnts/pdf2002/rose02a.pdf Notice the shingle temperatures...

As the house style won't accept soffit vents or roof edge vents: http://www.cor-a-vent.com/in-vent.cfm
you may want to go with a conditioned attic; http://www.buildingscience.com/documents/digests/bsd-149-unvented-roof-assemblies-for-all-climates


Code has requirements for this, you are in Zone 5 and about 15 days of snow- http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_8_sec006_par003.htm R-20 or 4" of foamboard, closed-cell, PLUS
this is code minimum (R-38) requirements, not "Energy Star" requirements, 6" of f.g. at R-19 would bring you to requirements.

Then you would be insulating in the rafter bays, not the attic floor at all, utilizing the space for mold-free storage with no fears. Close up the gable vents for good, reinstall the gable insulation after adding rigid f.b. first (equal to wall requirements). 

Be aware, loading cellulose on 1/2" drywall at 2' on-center framing: http://www.energyguide.com/library/EnergyLibraryTopic.asp?bid=austin&prd=10&TID=17324&SubjectID=8375 Just check before you spray.

Gary


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