[midwestfoam]

I know some of you have touched on the vaulted ceiling thing. Understand that half pound or 2 pound foam can be used for this application can someone give me there full opinion on this subject I would like as much info as possible the do and don't about the subject ventilation etc. thanks gerald

[21boat]

Some background on insulating ceilings.
Insulation code

http://www.southface.org/web/resourc...lings_4pdf.pdf

Compare Spray Foam | McGlaughlin Spray Foam Insulation

http://www.healthgoods.com/Education...insulation.htm

http://www.ornl.gov/sci/roofs+walls/...on/ins_08.html

http://www.healthgoods.com/Education...foam_board.htm

http://www.xpsa.com/tech/Tech%20Talk...lue%20Roof.pdf

Section 1203 of the 2006 IBC requires the total ventilation to be 1/150 of the of the space being vented. 50% of this venting should be by eave/cornice vents, the balance should be at least three feet above the eave/cornice vents. There is an exception that allows you to reduce the amount if ventilation to less - 1/300 if you have a vapor barrier installed on “the warm side”. A minimum of 1” clearance is required between roof sheathing and insulation in all cases.

I don't know what code your area is following, As of 2006. Check with your local building official. Your local municipality may have additional information pertaining to this section.
Basically if you baffle under the roof sheeting and spray the remainder with spray foam you should be good to go.

Spray foam is usually 3 times more expensive but the pay backs are quick

Foam is the best way to insulate without a doubt. Its perfect for vaulted ceilings simply because the rafters are to small in with to get the proper (R) value needed in that GEO