1.5.zip (2025)

The 1.5-inch panel is a composite material consisting of three primary layers:

: In Climate Zone 5, the R-6.6 provided by the 1.5-inch panel is sufficient to keep the sheathing boundary above the dew point, preventing internal condensation when using fiber insulation in the stud cavity. 4. Application and Code Compliance 1.5.zip

: A 1-inch thick layer of polyisocyanurate (polyiso) foam bonded to the back of the OSB. 1.5.zip

, significantly lower than standard OSB and housewrap combinations ( 3. Advantages in Construction 1.5.zip