Spray foam over fiberglass batt
I am building a new house that is required to have a fire sprinkler system. In order to prevent frozen pipes, they are “tented” with a R-38 kraft faced fiberglass batt.
I am in CZ 4, Maryland follows IECC 2015. I am attempting to build a “pretty good” house. My insulation plan for the ceiling is a 1″ layer of closed cell with R-49 blown in fiberglass on top of the closed cell. Attic is vented.
Will the 1″ of closed cell work over the top of the r-38 batts to provide an air barrier? I am having trouble locating good information about air sealing fire sprinklers. Should I have them cover the tops of the batts with 1/4″ fan fold? Or remove the batts and use 1/4″ fan fold as the top of the “tent” which would be sprayed with foam?
Ceiling has no can lights, just junction boxes for surface mount LED lights and pendants. Other penetrations include the sprinkler heads and outlet boxes for smoke alarm.
Thanks for any ideas and suggestions.
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