Johns Manville ComfortTherm® poly-encapsulated thermal and acoustical insulation offers R-Values up to R-30 and is available in precut batts to fit standard wall cavities or rolls for custom installation in any size of wall cavity. ComfortTherm® insulation is wrapped in plastic for dust-free, itch-free installation, and can be used in a wide variety of wood frame, engineered wood and steel frame construction applications, including new construction and retrofit.