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Author	Comments
David Stanislawski Posted: Jan 26, 2007 08:02 PM	Attic insulation I like to thank all who contribute to this board. Your knowledge is invaluable. I'm interested in insulating my attic with FOAM! I'm rather confused on which route to take. I have a contractor coming to give me an estimate on 4 inches of open cell sprayed to the roof deck and seal my attic (hot roof). I'm skeptical on the product he is going to use. Not sure I can list it here, but if your interested PLEASE e-mail me. Would 4 inches of open cell be enough? Or should I get an estimate on shooting closed cell onto the sheetrock? I'm assuming 2 inches of closed would be enough. I also have a cathedral ceiling in the master bedroom. There is plenty of clearance between the ceiling and the roof deck for foam; however, the one wall in the bedroom is up against the side of the house. Help guys. I really would appreciate it.
SprayFoamSupply.com Posted: Jan 26, 2007 08:23 PM	Where are you located. 4" of open cell in the roof will not meet code anywhere that I am aware of. George
Glenn Gamblin Posted: Jan 27, 2007 09:40 AM	You need at least 5 1/2 inches of foam on any roof deck and if you decide to go with closed I would recommend at least 3inches in the roofline or attic floor. Spraying the roofline and having a closed attic works excellent with lower pitched roofs and smaller attics, but if you have a huge attic, just have him spray the attic floor with 5 1/2 inches of open cell, you can't beat it. Just make sure that the can lights are sealed, but not sprayed over. Place a cardboard box or 5 gallon bucket over them before foaming. Also remember to check his work, if he bid you 4 inches, then his work is probably substandard. If the attic is not properly sealed, then it is defeating the purpose of foaming it.
David Stanislawski Posted: Jan 27, 2007 03:52 PM	Thanks for your responses gentlemen. The filterglass guys that installed the insulation when the home was build did a terrible job. I only have R-30 and there are many gaps and falling insualtion on the cathedral ceiling. Nothing is sealed in the attic. I can see light coming through from the light fictures below and bath fans, the wire penetrations are not seal, and there are gaps on the top plate where it meets the sheetrock. Are these the areas you are talking about sealing prior to foam? Also, I have no can lights and there is plenty of room to stand in my attic. I can take pictures and e-mail them to anyone that is interested in giving me suggestions. I think I will entertain the contractors bid and recommendations, but feel I will go else where thanks to all of you.
Glenn Gamblin Posted: Jan 28, 2007 07:23 PM	All the gaps will be filled as long as the applicator sprays everything. Just make sure that you are getting a good job by looking over the job after they finish and make sure that they have not missed any spots. Also, if there is already insulation in the attic you will have to remove it because it can not be sprayed over, or better yet, just have the attic sealed off. Make sure that at least 5 1/2 inches of open cell are applied to the roofline and gables and that any vents are sealed off. All vent pipes and bathroom fans will need to be vented to the outside to decrease the amount of moisture buildup. The closed attic is beneficial because it is putting your heating and cooling system in air conditioned space and it will work more efficiently. The duct work is only an R 6 rating. There is typically around 15 percent of leakage from your cooling system, which will heat and cool the attic. And remember, tell the contractor that you are very picky up front, sometimes that will make them rethink trying to con you. Feel free to email me any pictures if you need help. glenngamblin1@yahoo.com
Posted: Feb 03, 2007 04:50 PM	Stan, you need to make certain also about any combustion air requirement that you may have. I did not see any information regarding your AC system here. Likewise you may email me any pictures to kenneth@coolsprayllc.com or kenneth@coolservice.com. Spray foam is a great choice, make the contractor a great choice also. As bad as we all hate to admit it there are flakes in every industry. Kenneth
David Stanislawski Posted: Feb 05, 2007 02:20 AM	Thanks for the help guys. I'm gonna go with 4" of cc for the cathedral and 2" of cc on the flat surface in the attic and cover it with cellulose. The old fiber glass will go on top of the foam first. I know about the r-fairy tale, but I'll have and r-69 in my attic when I'm done. They keep raising the recommendations so I figure I should do it now and be done with it. Once I close the attic door I want to be done with it. Do it right the first time. I am working with a contractor and I'm also getting my rim joist sprayed. When the home was built they never sealed the gap between the foundation blocks and the decorative block. There is major cold air coming in. Ken sorry for the delay; I'll send u the pictures I took.
David Stanislawski Posted: Feb 16, 2007 09:47 PM	I received the estimate to have my attic and rim joist sprayed; I noticed in the estimate they will be using BIOFOAM. The contractors web site shows it is soy and castor oils. After reading the post prior to mine I don't believe this is my answer. Can I request he use another product that is a petroleum base? Please email me with reputable brands of oc and cc. Again, thank you all.
Thomas Kasper Posted: Feb 17, 2007 11:33 AM	Stan, I think the soy foam can give the installer trouble, but if it is done right it is done right. You will be able to tell. Watch for shrinkage and be certain it is laminated to the surface.(that goes for all foams) I spray soy oc for certain jobs, I like to use it in the attic down on drywall(vented attic) rim joists and sometimes under floors. These are my main applications for oc otherwise I go with cc. I don't use cc soy, at this time.

Author

Comments

David Stanislawski

Posted: Jan 26, 2007 08:02 PM

Attic insulation

I like to thank all who contribute to this board. Your knowledge is invaluable.
I'm interested in insulating my attic with FOAM! I'm rather confused on which route to take. I have a contractor coming to give me an estimate on 4 inches of open cell sprayed to the roof deck and seal my attic (hot roof). I'm skeptical on the product he is going to use. Not sure I can list it here, but if your interested PLEASE e-mail me.
Would 4 inches of open cell be enough? Or should I get an estimate on shooting closed cell onto the sheetrock? I'm assuming 2 inches of closed would be enough.
I also have a cathedral ceiling in the master bedroom. There is plenty of clearance between the ceiling and the roof deck for foam; however, the one wall in the bedroom is up against the side of the house.
Help guys. I really would appreciate it.

SprayFoamSupply.com

Posted: Jan 26, 2007 08:23 PM

Where are you located. 4" of open cell in the roof will not meet code anywhere that I am aware of.

George

Glenn Gamblin

Posted: Jan 27, 2007 09:40 AM

You need at least 5 1/2 inches of foam on any roof deck and if you decide to go with closed I would recommend at least 3inches in the roofline or attic floor. Spraying the roofline and having a closed attic works excellent with lower pitched roofs and smaller attics, but if you have a huge attic, just have him spray the attic floor with 5 1/2 inches of open cell, you can't beat it. Just make sure that the can lights are sealed, but not sprayed over. Place a cardboard box or 5 gallon bucket over them before foaming. Also remember to check his work, if he bid you 4 inches, then his work is probably substandard. If the attic is not properly sealed, then it is defeating the purpose of foaming it.

David Stanislawski

Posted: Jan 27, 2007 03:52 PM

Thanks for your responses gentlemen.
The filterglass guys that installed the insulation when the home was build did a terrible job. I only have R-30 and there are many gaps and falling insualtion on the cathedral ceiling.
Nothing is sealed in the attic. I can see light coming through from the light fictures below and bath fans, the wire penetrations are not seal, and there are gaps on the top plate where it meets the sheetrock. Are these the areas you are talking about sealing prior to foam?
Also, I have no can lights and there is plenty of room to stand in my attic.
I can take pictures and e-mail them to anyone that is interested in giving me suggestions.
I think I will entertain the contractors bid and recommendations, but feel I will go else where thanks to all of you.

Glenn Gamblin

Posted: Jan 28, 2007 07:23 PM

All the gaps will be filled as long as the applicator sprays everything. Just make sure that you are getting a good job by looking over the job after they finish and make sure that they have not missed any spots. Also, if there is already insulation in the attic you will have to remove it because it can not be sprayed over, or better yet, just have the attic sealed off. Make sure that at least 5 1/2 inches of open cell are applied to the roofline and gables and that any vents are sealed off. All vent pipes and bathroom fans will need to be vented to the outside to decrease the amount of moisture buildup. The closed attic is beneficial because it is putting your heating and cooling system in air conditioned space and it will work more efficiently. The duct work is only an R 6 rating. There is typically around 15 percent of leakage from your cooling system, which will heat and cool the attic. And remember, tell the contractor that you are very picky up front, sometimes that will make them rethink trying to con you. Feel free to email me any pictures if you need help. glenngamblin1@yahoo.com

Posted: Feb 03, 2007 04:50 PM

Stan, you need to make certain also about any combustion air requirement that you may have. I did not see any information regarding your AC system here. Likewise you may email me any pictures to kenneth@coolsprayllc.com or kenneth@coolservice.com. Spray foam is a great choice, make the contractor a great choice also. As bad as we all hate to admit it there are flakes in every industry. Kenneth

David Stanislawski

Posted: Feb 05, 2007 02:20 AM

Thanks for the help guys. I'm gonna go with 4" of cc for the cathedral and 2" of cc on the flat surface in the attic and cover it with cellulose. The old fiber glass will go on top of the foam first.
I know about the r-fairy tale, but I'll have and r-69 in my attic when I'm done. They keep raising the recommendations so I figure I should do it now and be done with it. Once I close the attic door I want to be done with it. Do it right the first time.
I am working with a contractor and I'm also getting my rim joist sprayed. When the home was built they never sealed the gap between the foundation blocks and the decorative block. There is major cold air coming in.
Ken sorry for the delay; I'll send u the pictures I took.

David Stanislawski

Posted: Feb 16, 2007 09:47 PM

I received the estimate to have my attic and rim joist sprayed; I noticed in the estimate they will be using BIOFOAM. The contractors web site shows it is soy and castor oils. After reading the post prior to mine I don't believe this is my answer.
Can I request he use another product that is a petroleum base? Please email me with reputable brands of oc and cc.
Again, thank you all.

Thomas Kasper

Posted: Feb 17, 2007 11:33 AM

Stan,
I think the soy foam can give the installer trouble, but if it is done right it is done right. You will be able to tell. Watch for shrinkage and be certain it is laminated to the surface.(that goes for all foams) I spray soy oc for certain jobs, I like to use it in the attic down on drywall(vented attic) rim joists and sometimes under floors. These are my main applications for oc otherwise I go with cc. I don't use cc soy, at this time.

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