When designing and building a cathedral ceiling using spray foam insulation you need to take into account code related to.
Vaulted ceiling insulation code.
Building codes require a minimum amount of insulation in ceilings and exterior walls to help a house maintain consistent temperature.
But codes rarely make the distinction between attics and cathedral ceilings in the minimum insulation requirements.
This article series gives suggestions for insulating cathedral ceilings on older homes providing under roof ventilation for cathedral ceilings while obtaining higher insulation values or r values for these areas.
Section r806 4 local codes based on irc 2012.
Unvented cathedral ceiling code local codes based on irc 2009.
Retrofit or add on cathedral ceiling insulation questions answers set 2.
Section r806 1 local codes based on irc 2012.
R 38 shall be deemed to satisfy the requirement for r 49 wherever the full height of uncompressed r 38 insulation extends over the wall top plate at the eaves.
The 2015 irc requires r 49 insulation for ceilings with attic spaces.
However there is an exception.
How to install fiberglass insulation in vaulted ceilings.
Pa302 1 ceilings with attic spaces n1102 2 1 r402 2 1.
Section r806 5 vented cathedral ceiling code local codes based on irc 2009.
Bernice from midland ontario wants to know how to get more insulation into her vaulted or cathedral ceiling the common problem with structures like this that we call compact roofs is that there is not usually enough space for a lot of insulation and a lot of ventilation.