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Gerry Wagoner Posted: Mar 24, 2006 12:19 PM	What thickness are you guys spraying for attic envelopes? We are spraying 4" of rigid or, 8" of half-pound. Working well. gcw
Posted: Mar 24, 2006 07:22 PM	what is your climate zone? are you applying to these depths and covering with a less expensive product to obtain rvalue design specs? or are you applying to these depths with no additional material added? when i apply an attic envelope..shooting down to the drywall lid,,i will apply 2" closed cell or 3-4" open cell to detail the lids penetrations and to create a uniform air barrier and then have the fiberglass crew blow to an r-40 minimum total..in the larger customs i encourage the owner to allow the glass to be applied to an r-50,,it dont cost that much more at this time,,and the dept of energy has recently increased their recomendations,,,and will again im sure if our energy costs continue to rise... i tend to shoot cathedrals and vaults to design specs, either material,,,when space allows.. and obviously a closed cell in area's that have space restrictions prohibiting a decent rvalue.
Posted: Mar 24, 2006 11:57 PM	What exactly do you mean by attic envelope?
Posted: Mar 25, 2006 05:39 PM	that is the term i use when i go into the attic and shoot down onto the drywall lid to seal the lid and complete the building envelope... i shoot the minimum of foam to do the job right and then a fiberglass crew installs to R40 total to meet design specs...this is affordable for the consumer...
Posted: Mar 25, 2006 06:20 PM	When the sheetrock meets the eve, how are you getting that with the foam? Are you crawling on your belly? If so, how are you avoiding falling through the sheetrock? What are you putting, 2" of foam and then R-40 blow-in on top of that? Thanks.
Posted: Mar 26, 2006 07:03 AM	Q:When the sheetrock meets the eve, how are you getting that with the foam? Are you crawling on your belly? sometimes,,yes,,4:12's are a bitch..figure its gonna take more product out there.. If so, how are you avoiding falling through the sheetrock? by not getting on the rock..stepped thru once.in my first year..short cross planks to put across the rafters helps sometimes..moveing them is a pain and slows the process.. What are you putting, 2" of foam and then R-40 blow-in on top of that? depends..2" closed cell will allow me to do the job right (ie: seal the lid)i have sprayed 3-4 inch closed cell upstairs before and,,when allowed to cure..it becomes solid enough to step onto without going thru the lid..i still avoid this though,,an ounce of prevention is worth a pound of cure.. 3-4" open cell...this works good for the truss heels...point blast away and watch her rise... some jurisdictions will not allow exposed foam in the attic either...(damn stuffs explosive ya know!) and want it covered with cell or glass. remember R value is R value..foam is not a "miracle product" and you "only need R19 of it in an attic". bull hunky,,thats what you got R19,,dont matter if its foam, glass,,cell or poop r-19 is r-19. i have personally witnessed r19 open cell foam in an attic,,hole cut into rock lid then foam to install speakers..water running out of foam..(skin held it in)r19 is not enough to prevent condensation in our cold weather zone..r19 in a lid will not manifest "40-50% energy savings" by using foams..nor will 2/4" in sidewalls..r value is r value..yes we stop uncontrolled air movement into and out of the wall cavity..and this does allow the wall to maintain design rvalues in adverse environmental conditions.. where traditional insulation products tend to loose some of their thermal performance.. let me see if i can dig up an interesting article on this design failure...
Posted: Mar 26, 2006 07:20 AM	sorry,,i missed the last 1/2 of question #2 yes we are then blowing to R-40 total (although, if the customer is paying for a foam upgrade..i tell em to go to r50..its cheaper to do it now than later, and with the energy costs sky rocketing..dept of energys attic rvalue recomendations are being elevated in some areas, may as well do it now..and glass/cell is cheap)
Gerry Wagoner Posted: Mar 26, 2006 09:23 AM	Hi guys. Thanks for your input. We are in Ohio. The attic envelope is a term referring to insulating the underside of a roof deck with spray foam. This turns the attic into conditioned air, free from the hot & cold swings normally experienced in an attic. Sometimes it is referred to as unvented attics. gcw
Gerry Wagoner Posted: Mar 26, 2006 09:29 AM	Our experience with fiberglass indicates that it is the absolute least effective insulation in the market. Cellulose is far better (not as good as foam of course) at loose fill in an attic situation. ORNL (Oak Ridge national Laboratory) has demonstrated the incredible weakness of fiberglass as an insulation material. Recently they tested both foams (open and closed) and fiberglass in an attic situation. Results at 0°: fiberglass retained 47% of its stated R-value Open Cell retained 74% Closed cell retained 84% interesting, eh? gcw
Posted: Mar 26, 2006 03:33 PM	Olger, do you have a link to a web site that gives that info.? I would like to print it out and have it with me when I talk to customers. Thanks
Posted: Mar 26, 2006 09:15 PM	www.sprayfoam.org (spfa) has the document..
Posted: Mar 29, 2006 09:40 PM	Again I have to disagree with foamdude. No foam is not a miracle product, but R- value only takes into consideration conductive properties. It doesn't deal with convection or radiation. There are a lot of real world problems that are remedied with foam starting with the major form of heat lose. The thermal stacking effect.R-14 sidewalls and an R-21-28 attic will be as cost effective as you can get. Spraying more would only waste homeowners money.Lets be realistic we don't need to pour 2' think basement walls that would be a waste of money.
Posted: Mar 30, 2006 07:02 PM	you are absolutely correct..real world experience tells us this is true... but the energy companys,,the government...builders,,architects & homeowners want to see numbers,,not ancedotal evidence...there is a thing called code...should we knowingly endorse applying to less than mandated levels? how do these lower r values walls affect the structures energy star rating (read REBATE)...
Posted: Mar 30, 2006 09:43 PM	I understand where you are coming from our hands are tied with R-value rope.Someone once compared R-value to land. Lets say 1 acre is 1 acre, However if someone offered to sell it to us for $10,000 sound good but is that enough info. I would want to know more,is it rocky, flat, wetland dry? To me there is a lot of similarity, you cant just sell land based on the size. You shouldn't sell insulation just based on R-value. I have a home show display that is a box with 3 dividers 1-2"foam R-14 1-9" cellulose 1-10"fiberglass. I heat the lower box to 160 degrees and put thermometers 1" from top of insulation in each, the foam maintains 5 degrees above ambient temp continously after thermal saturation, the cellulose 20 degrees above ambient and the fiberglass about 60 degrees above ambient temp. Remember the foam is rated R-14 the cell and fiberglass are both rated R-30 go figure.
Gerry Wagoner Posted: Mar 31, 2006 10:03 AM	About this demo. Did you buy or make it? Thanks, gcw
Posted: Apr 01, 2006 08:42 AM	bought mine...$500 last i looked.. fiber/foam/cell is good for the home show table..
Gerry Wagoner Posted: Apr 11, 2006 12:58 PM	Thanks. Where can I purchase a foam/fiber/glass display? gcw
SprayFoamSupply.com Posted: Apr 11, 2006 08:35 PM	Here you are Mr. GCW http://www.macsimum.com/products.asp?filter=N George
Gerry Wagoner Posted: Apr 12, 2006 01:20 PM	:)
Posted: Apr 17, 2006 12:05 PM	Sorry Olger I wasn't ignoring you haven't been on the forum for some time business has been crazy. Just finally checking in today 4/17 I made mine if interested I'd be happy to E-mail you pictures of it. We need to all be doing home shows and the like to promote this industry.With fuel prices where they are its our time to clear the muddy waters made by the fiber manufactures. Well I better get back to work.
SprayFoamSupply.com Posted: Apr 19, 2006 08:42 PM	I'd like some pics of your homemade unit. It's over $500 with shipping to buy one. George info@nhsprayfoammagazine.com

Author

Comments

Gerry Wagoner

Posted: Mar 24, 2006 12:19 PM

What thickness are you guys spraying for attic envelopes?

We are spraying 4" of rigid or,
8" of half-pound.

Working well.

gcw

Posted: Mar 24, 2006 07:22 PM

what is your climate zone?
are you applying to these depths and covering with a less expensive product to obtain rvalue design specs?
or are you applying to these depths with no additional material added?

when i apply an attic envelope..shooting down to the drywall lid,,i will apply 2" closed cell or 3-4" open cell to detail the lids penetrations and to create a uniform air barrier and then have the fiberglass crew blow to an r-40 minimum total..in the larger customs i encourage the owner to allow the glass to be applied to an r-50,,it dont cost that much more at this time,,and the dept of energy has recently increased their recomendations,,,and will again im sure if our energy costs continue to rise...
i tend to shoot cathedrals and vaults to design specs, either material,,,when space allows.. and obviously a closed cell in area's that have space restrictions prohibiting a decent rvalue.

Posted: Mar 24, 2006 11:57 PM

What exactly do you mean by attic envelope?

Posted: Mar 25, 2006 05:39 PM

that is the term i use when i go into the attic and shoot down onto the drywall lid to seal the lid and complete the building envelope...
i shoot the minimum of foam to do the job right and then a fiberglass crew installs to R40 total to meet design specs...this is affordable for the consumer...

Posted: Mar 25, 2006 06:20 PM

When the sheetrock meets the eve, how are you getting that with the foam? Are you crawling on your belly? If so, how are you avoiding falling through the sheetrock?

What are you putting, 2" of foam and then R-40 blow-in on top of that?

Thanks.

Posted: Mar 26, 2006 07:03 AM

Q:When the sheetrock meets the eve, how are you getting that with the foam? Are you crawling on your belly?
sometimes,,yes,,4:12's are a bitch..figure its gonna take more product out there..
If so, how are you avoiding falling through the sheetrock?
by not getting on the rock..stepped thru once.in my first year..short cross planks to put across the rafters helps sometimes..moveing them is a pain and slows the process..

What are you putting, 2" of foam and then R-40 blow-in on top of that?
depends..2" closed cell will allow me to do the job right (ie: seal the lid)i have sprayed 3-4 inch closed cell upstairs before and,,when allowed to cure..it becomes solid enough to step onto without going thru the lid..i still avoid this though,,an ounce of prevention is worth a pound of cure..
3-4" open cell...this works good for the truss heels...point blast away and watch her rise...

some jurisdictions will not allow exposed foam in the attic either...(damn stuffs explosive ya know!) and want it covered with cell or glass.

remember R value is R value..foam is not a "miracle product" and you "only need R19 of it in an attic". bull hunky,,thats what you got R19,,dont matter if its foam, glass,,cell or poop r-19 is r-19.

i have personally witnessed r19 open cell foam in an attic,,hole cut into rock lid then foam to install speakers..water running out of foam..(skin held it in)r19 is not enough to prevent condensation in our cold weather zone..r19 in a lid will not manifest "40-50% energy savings" by using foams..nor will 2/4" in sidewalls..r value is r value..yes we stop uncontrolled air movement into and out of the wall cavity..and this does allow the wall to maintain design rvalues in adverse environmental conditions..
where traditional insulation products tend to loose some of their thermal performance..

let me see if i can dig up an interesting article on this design failure...

Posted: Mar 26, 2006 07:20 AM

sorry,,i missed the last 1/2 of question #2
yes we are then blowing to R-40 total (although, if the customer is paying for a foam upgrade..i tell em to go to r50..its cheaper to do it now than later, and with the energy costs sky rocketing..dept of energys attic rvalue recomendations are being elevated in some areas, may as well do it now..and glass/cell is cheap)

Gerry Wagoner

Posted: Mar 26, 2006 09:23 AM

Hi guys. Thanks for your input.

We are in Ohio. The attic envelope is a term referring to insulating the underside of a roof deck with spray foam. This turns the attic into conditioned air, free from the hot & cold swings normally experienced in an attic. Sometimes it is referred to as unvented attics.

gcw

Gerry Wagoner

Posted: Mar 26, 2006 09:29 AM

Our experience with fiberglass indicates that it is the absolute least effective insulation in the market. Cellulose is far better (not as good as foam of course) at loose fill in an attic situation.

ORNL (Oak Ridge national Laboratory) has demonstrated the incredible weakness of fiberglass as an insulation material. Recently they tested both foams (open and closed) and fiberglass in an attic situation. Results at 0°:

fiberglass retained 47% of its stated R-value
Open Cell retained 74%
Closed cell retained 84%

interesting, eh?

gcw

Posted: Mar 26, 2006 03:33 PM

Olger, do you have a link to a web site that gives that info.? I would like to print it out and have it with me when I talk to customers.

Thanks

Posted: Mar 26, 2006 09:15 PM

www.sprayfoam.org (spfa) has the document..

Posted: Mar 29, 2006 09:40 PM

Again I have to disagree with foamdude. No foam is not a miracle product, but R- value only takes into consideration conductive properties. It doesn't deal with convection or radiation. There are a lot of real world problems that are remedied with foam starting with the major form of heat lose. The thermal stacking effect.R-14 sidewalls and an R-21-28 attic will be as cost effective as you can get. Spraying more would only waste homeowners money.Lets be realistic we don't need to pour 2' think basement walls that would be a waste of money.

Posted: Mar 30, 2006 07:02 PM

you are absolutely correct..real world experience tells us this is true...
but the energy companys,,the government...builders,,architects & homeowners want to see numbers,,not ancedotal evidence...there is a thing called code...should we knowingly endorse applying to less than mandated levels? how do these lower r values walls affect the structures energy star rating (read REBATE)...

Posted: Mar 30, 2006 09:43 PM

I understand where you are coming from our hands are tied with R-value rope.Someone once compared R-value to land. Lets say 1 acre is 1 acre, However if someone offered to sell it to us for $10,000 sound good but is that enough info. I would want to know more,is it rocky, flat, wetland dry? To me there is a lot of similarity, you cant just sell land based on the size. You shouldn't sell insulation just based on R-value. I have a home show display that is a box with 3 dividers 1-2"foam R-14 1-9" cellulose 1-10"fiberglass. I heat the lower box to 160 degrees and put thermometers 1" from top of insulation in each, the foam maintains 5 degrees above ambient temp continously after thermal saturation, the cellulose 20 degrees above ambient and the fiberglass about 60 degrees above ambient temp. Remember the foam is rated R-14 the cell and fiberglass are both rated R-30 go figure.

Gerry Wagoner

Posted: Mar 31, 2006 10:03 AM

About this demo. Did you buy or make it?

Thanks,

gcw

Posted: Apr 01, 2006 08:42 AM

bought mine...$500 last i looked..
fiber/foam/cell
is good for the home show table..

Gerry Wagoner

Posted: Apr 11, 2006 12:58 PM

Thanks. Where can I purchase a foam/fiber/glass display?

gcw

SprayFoamSupply.com

Posted: Apr 11, 2006 08:35 PM

Here you are Mr. GCW
http://www.macsimum.com/products.asp?filter=N

George

Gerry Wagoner

Posted: Apr 12, 2006 01:20 PM

Posted: Apr 17, 2006 12:05 PM

Sorry Olger
I wasn't ignoring you haven't been on the forum for some time business has been crazy. Just finally checking in today 4/17
I made mine if interested I'd be happy to E-mail you pictures of it. We need to all be doing home shows and the like to promote this industry.With fuel prices where they are its our time to clear the muddy waters made by the fiber manufactures.
Well I better get back to work.

SprayFoamSupply.com

Posted: Apr 19, 2006 08:42 PM

I'd like some pics of your homemade unit. It's over $500 with shipping to buy one.

George

info@nhsprayfoammagazine.com

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