What needs to go behind a shower surround on an exterior wall with 2″ of exterior foam sheathing?
ecoecompany
| Posted in Green Building Techniques on
I have a client doing a whole house remodel. They’ve already wrapped the entire exterior with 2″ of EPS and are insulating the interior with blown in fiberglass. What insulation / air sealing is needed behind the fiberglass shower surround on an exterior wall to achieve a dry, air-sealed envelope? Can they get away with just fiberglass batts there or is a rigid air barrier needed on the interior?
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Replies
Elizabeth,
Fiberglass batts can work if they are installed carefully. Of course, the exterior EPS needs to be thick enough to keep the stud bays above the dew point during the winter.
If the wall studs are filled with fiberglass batts, the batts need to be covered with a durable air barrier (gypsum drywall or ThermoPly) before the fiberglass tub shower is installed. All of the seams in the air barrier must be carefully sealed.