Spray-foam has a reputation of providing superior insulating qualities compared to fiberglass batt, mineral wool, cellulose, and other insulation alternatives.
Johns Manville (JM) has announced that JM Corbond III® closed-cell spray polyurethane foam insulation now delivers an R-value of R-7 per inch, a change that translates to a 9-percent increase in thermal resistance compared to the previous R-6.4 per inch.