Due to aesthetics, R-20 (4 1/2 inches of rigid foam) above the roof is my limit
Due to aesthetics, R-20 (4 1/2 inches of rigid foam) above the roof is my limit. Would Roxul plus an airspace in the rafter bays be a good choice for the remainder of the needed R-value?
Jesse, 80% of home is concrete slab with remaining 20% being crawl space I closed in - conditioned basement. In a high water table area with no vapor barrier under slab or crawl. De-humidifier runs constantly.
I plan to include air space in rafter bays under sheathing along with batt insulation for remainder of needed R-value. Is an airspace necessary with R-20 foam above roof sheathing?
Posted Tue, 07/01/2014 - 09:31
Edited Tue, 07/01/2014 - 10:34
Other Questions in Green building techniques