Insulating a strapped attic floor
Need to insulate an attic floor with 24oc/12in high truss joists that have been strapped with 1×3 strapping, 16 oc across the underneath of the joists. 1/2 blue board is attached under the strapping and veneer plaster makes up the ceiling. 2 coats of Behr ceiling paint is on the plaster.
My concern. The strapping creates a space under the joists, so it’ll make the joist bays “connected”. Air could communicate from bay to bay if I were to use unfaced roxul batts which is my preference because I have plenty. I also have some cellulose that I could spread as my first layer to fill the voids that the strapping made.
What are my options?
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