Helpful? 0

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?

Asked by cameron morris
Posted Tue, 07/01/2014 - 09:31
Edited Tue, 07/01/2014 - 10:34

Tags:

1 Answer

Select your preferred way to display the comments and click "Save settings" to activate your changes.
1.
Helpful? 0

Cameron,
It looks like you intended to post this on a different page. In most cases, it makes sense to maintain just one thread for a series of questions, rather than starting a new thread each time.

Here is a link to the original thread:
http://www.greenbuildingadvisor.com/community/forum/green-building-techn...

It would be a good idea to post all answers back on that page.

Answered by Martin Holladay, GBA Advisor
Posted Tue, 07/01/2014 - 10:36

Other Questions in Green building techniques

How do deviations in average winter temperature affect energy consumption?

In Energy efficiency and durability | Asked by norm farwell | Oct 24, 14

Flat roof insulation

In Energy efficiency and durability | Asked by Angela M | Nov 22, 13

Roof insulation

In GBA Pro help | Asked by Steven Clark | Oct 24, 14

Add R-14 Roxul between the garage attic and the house?

In Energy efficiency and durability | Asked by Mike Lucas | Oct 23, 14
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!