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Discussion Starter #1
Hi all,

I have some questions on dormer insulation/air flow

The dormers on the house are gable dormers with flat ceiling joists. There will be insulation in the flat ceiling joists.

The space above the ceiling joist is connected to the attic space, but not such that I will be able to use the blown in insulation that I will use in the attic.

The dormers do not have ridge vents.

Question #1

Do I use R30 or R38 insulation in the dormer ceiling? (code requires R-38, but don't know if this would be applicable to the dormer ceiling since it's 10/12 pitch and R-38 would be really tall out at the eaves)


Question #2

Do the soffits on the dormers need to be vented?

Question #3 will be answered by question #2 which will is do I need to use spacers on the roof of the dormers to keep the insulation from stopping air flow.


Thanks, Mike
 

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Yes you need baffles and a small ridge vent.
It's no different then any other roof on the house.
 
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Discussion Starter #3
Hi Joe,

The person who installed the shingles and also the county inspector indicated I don't need to vent the dormer. I received an answer from them after I posted this.

The inspector indicated that since the dormers were part of the attic circuit, vents would not be required. I also read somewhere that if the dormer ridge were lower than the main ridge that venting the dormer ridge would short circuit the main soffit to ridge vent flow.
 
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