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jackpine 12-05-2011 07:59 PM

New Insulation problem
 
I am in the process of vaulting our upstairs ceiling and have finally come to the insulation step. My wife brought me home 10 batts of unfaced R38 that is supposed to be 16" wide and 12" thick, 4 feet long BU80 is the code number on it, Owens Corning.

I cut the bags open and was surprised that the batts didn't expand hardly at all, maybe got 6 to 8 inches thick. Well I shook them out best I could and put them up, disappointing but figuring that maybe this is the way the stuff is. (I am not experienced in insulation matters). It kind of sags in between the rafters even, not wanting to stay up. I am going to poly it so again, I was not real happy.

Well, I finished those 10 bundles and my wife brought me a second 10 bundle load home. I cut the first one open and all the batts in that bundle expanded to the 12 inches thick, nice fluffy and they friction fit great in the cavities!

Now I am faced with the thought that maybe there was a problem with the first load that I fought to stick up in the rafters. Should I tear it all down and bring it back? And how does one go about bringing back 430 square feet of insulation?

ratherbefishing 12-06-2011 12:54 AM

It sounds to me that a call to Owens Corning is in order.

jackpine 12-06-2011 02:41 PM

Here is a photo of the good one and the bad one. I am not pleased at all right now.

http://img.photobucket.com/albums/v2...hunter/321.jpg

joecaption 12-06-2011 03:05 PM

Why are you not using faced insulation instead of unfaced?
What's the width of these rafters your trying to fit this insulation in.
I've never seen 2 X 12 rafters before.
http://insulation.owenscorning.com/a...ddec360170.pdf
By the pictures your showing this sure looks like 2 totaly differant products.

jackpine 12-06-2011 03:15 PM

Quote:

Originally Posted by joecaption (Post 787565)
Why are you not using faced insulation instead of unfaced?
What's the width of these rafters your trying to fit this insulation in.
I've never seen 2 X 12 rafters before.
http://insulation.owenscorning.com/a...ddec360170.pdf
By the pictures your showing this sure looks like 2 totaly differant products.

Even though I didn't ask those questions, I will answer them. I originally had 2x6 rafters with r19 crammed in there and no vents. I am vaulting the ceiling. I since then put continuous soffet vents in, cut in and installed a ridge vent continuous, then furred down the 2x6 with ripped osb with a 2x2 attached to give me 14 inches of room for ventilation and 12 inches of r38. Collar ties on every third rafter and will be putting poly on before the tongue and groove pine.

Yes, looks like two different products yet same code, BU80.

Rod Barney 12-06-2011 07:02 PM

Just a comment:I experienced the same exact thing except the insulation was Johns Manville.Two identical bags, one bag expanded to 10-12 inches (per batt) when I cut it open, the other stayed at about 6 inches. I work for an insulation company and I called the warehouse about it, they said it would expand over time with gravity and it did.

Windows on Wash 12-06-2011 09:54 PM

Quote:

Originally Posted by jackpine (Post 787573)
Even though I didn't ask those questions, I will answer them. I originally had 2x6 rafters with r19 crammed in there and no vents. I am vaulting the ceiling. I since then put continuous soffet vents in, cut in and installed a ridge vent continuous, then furred down the 2x6 with ripped osb with a 2x2 attached to give me 14 inches of room for ventilation and 12 inches of r38. Collar ties on every third rafter and will be putting poly on before the tongue and groove pine.

Yes, looks like two different products yet same code, BU80.

T&G leaks a ton of air. You need to make sure that vapor barrier/air barrier is complete and sealed.

Do you have any can lights in this proposed assembly?

I would suggest you re-visit the insulation detail if it is not too late. I think you would have been better suited with construction of your own vent chutes made from rigid foam and 1-2" spacers of rigid foam against the deck. You then could dense pack that cavity with cellulose for an air barrier to prevent any migrating air through the roof assembly.

The 2" of XPS would give you an R-10 + the R-28 of the cellulose (8") will give you and R-38, add 2" of taped and sealed foil faced iso (no additional vapor barrier required) and you have an R-51 in total.

Ceiling R-value requirement in zones 6 and 7 are R-49. By the time you figure in the thermal bridging of your current assembly, it is less than R-30.

Air loss will carry +20X as much moisture as diffusion so make sure it is sealed up.

jackpine 12-06-2011 10:13 PM

Quote:

Originally Posted by Windows on Wash (Post 787886)
T&G leaks a ton of air. You need to make sure that vapor barrier/air barrier is complete and sealed.

Do you have any can lights in this proposed assembly?

I would suggest you re-visit the insulation detail if it is not too late. I think you would have been better suited with construction of your own vent chutes made from rigid foam and 1-2" spacers of rigid foam against the deck. You then could dense pack that cavity with cellulose for an air barrier to prevent any migrating air through the roof assembly.

The 2" of XPS would give you an R-10 + the R-28 of the cellulose (8") will give you and R-38, add 2" of taped and sealed foil faced iso (no additional vapor barrier required) and you have an R-51 in total.

Ceiling R-value requirement in zones 6 and 7 are R-49. By the time you figure in the thermal bridging of your current assembly, it is less than R-30.

Air loss will carry +20X as much moisture as diffusion so make sure it is sealed up.

I appreciate your advice but it is too late. I am returning the defective R38 Tomorrow morning and replacing it with good product. I will be especially careful to make sure the poly is tight and I have considered foil faced foam before I put up the paneling. Money is a factor, that foam is expensive stuff. Going from a screwed up no vent R19 that created ice dams and damaged shingles and sheeting, this will be so much better. I did look into your way but just the money factor and the fact that I am living in this house right now, it isn't feasible.

Windows on Wash 12-06-2011 10:36 PM

Make sure you at least get the high density batts and sealing the baffles for proper air tightness will go along way.

http://www.buildingscience.com/docum...f-venting/view

Gary in WA 12-07-2011 09:55 PM

WW, seems like I've seen that link before..... recently...

" I am vaulting the ceiling. I since then put continuous soffet vents in, cut in and installed a ridge vent continuous, then furred down the 2x6 with ripped osb with a 2x2 attached to give me 14 inches of room for ventilation and 12 inches of r38. Collar ties on every third rafter and will be putting poly on before the tongue and groove pine."---- bold is mine. Did you remove any framing from the attic structure? Collar ties do not replace rafter ties--- two different beasts; http://publicecodes.citation.com/ico...002_par018.htm

Is the ridge a board or a beam?

Gary

jackpine 12-08-2011 10:56 AM

Quote:

Originally Posted by GBR in WA (Post 788708)
Seems like I've seen that link before..... recently...

" I am vaulting the ceiling. I since then put continuous soffet vents in, cut in and installed a ridge vent continuous, then furred down the 2x6 with ripped osb with a 2x2 attached to give me 14 inches of room for ventilation and 12 inches of r38. Collar ties on every third rafter and will be putting poly on before the tongue and groove pine."---- bold is mine. Did you remove any framing from the attic structure? Collar ties do not replace rafter ties--- two different beasts; http://publicecodes.citation.com/ico...002_par018.htm

Is the ridge a board or a beam?

Gary

Thanks for your concern but this seems to be an insulation thread.

Windows on Wash 12-08-2011 05:45 PM

Uh oh...

http://media.247sports.com/Uploads/B...424/290249.jpg

jackpine 12-08-2011 07:49 PM

Quote:

Originally Posted by Windows on Wash (Post 787913)
Make sure you at least get the high density batts and sealing the baffles for proper air tightness will go along way.

http://www.buildingscience.com/docum...f-venting/view

Because of your advise I purchased 500 bucks worth of foil faced rigid foam insulation to put up as an interior vapor barrier. I hope you are correct or I will have to send you a bill :)

I stopped listening to advice from some members here because all they want to do is spout code back and not answer my questions properly. If money wasn't an issue, or if I lived in a town that had strict building codes, it would be beneficial. All I can say to them is that they should have seen the structure before I started improving it, something they don't understand. Thank you for your advice and for making sense.

Oh, as far as the insulation, Home Depot replaced every single batt. It is opened up and expanding to the proper width and I am happy I took the original purchase stuff back. Don't buy insulation that has sat in a store for years, that is my advise after this.

Windows on Wash 12-08-2011 09:11 PM

Good luck with the project.

I think you will be pleasantly surprised with the overall comfort improvement.

Send the bill to :whistling2:

Gary in WA 12-12-2011 07:58 PM

Jackpine, this was not addressed to you; "Seems like I've seen that link before..... recently..."--- it was for WW as he and I posted in another link recently where I first used that article by Joe. I'll fix it now.

I can't keep all the links straight, due to getting older or ..... I don't want a roof system falling on a poster, so I sometimes read more between the lines..... Sorry if I brought up some bad thoughts for you, though checking your older posts, my answers were last in 5 of them, so hopefully they helped.

Gary


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