Is Johns Manville insulation good?

Yes, Johns Manville insulation is considered very good and is one of the most respected insulation brands among contractors, builders, and energy auditors in the United States. Johns Manville has been in business since 1858, is owned by Berkshire Hathaway, and manufactures its products in the USA with strict quality control. Its residential fiberglass line, including ComfortTherm encapsulated batts and Climate Pro blown-in fiberglass, is well regarded because it uses a formaldehyde-free bio-based binder that produces less dust and itching than older fiberglass, and it is GREENGUARD Gold certified for low chemical emissions. Contractors often prefer Johns Manville over Owens Corning Pink because it is typically 10 to 15 percent cheaper per square foot while delivering the same R-value and ASTM performance. In independent tests, Johns Manville batts achieve their labeled R-value consistently and resist settling. Its Spider spray-in fiberglass system is considered one of the best wall insulation systems for new construction because it fills all gaps and achieves R15 in 2x4 walls and R23 in 2x6 walls with excellent air sealing. Its mineral wool MinWool products are excellent for soundproofing and fire safety, rated for 2-hour fire walls. The only downsides mentioned by installers are that Johns Manville batts can be slightly less rigid than Owens Corning, so they need stapling in some cases, and retail availability is more limited in some eastern states. Overall it is a high-quality, professional-grade insulation.