What R-value Do I Need? | Johns Manville
https://www.jm.com/en/homeowner-insulation/homeowner-faq/what-r-value-do-i-need-/
WEBDepending on where you live and the part of your home you’re insulating (walls, crawlspace, attic, etc.), you’ll need a different R-Value. Typical recommendations for exterior walls are R-13 to R-23, while R-30, R-38 and R-49 are common for ceilings and attic spaces.
DA: 29 PA: 38 MOZ Rank: 19