Get this Owens Corning R-1 Rigid Insulation – FOAMULAR for delivery. Dimensions: 1/4 in. x 4 ft. x 50 ft.. Insulation Application: backer board for under new or replacement siding. Closed cell light weight foam board. Thermal performance of R1. FOAMULAR 150 and 250 are available in various thicknesses and R-values, the difference is the compressive strength, FOAMULAR 150 has a compressive strength of 15 psi and FOAMULAR 250 is 25 psi. FOAMULAR is not rated for STC (sound transmission) and does not have any soundproofing properties. When using FOAMULAR or any low perm insulation, always verify the moisture vapor flow and dew point characteristics of the wall system, please check your local building codes for vapor retarder/barrier information. Being used in an interior construction application, painting the FOAMULAR is not recommended as FOAMULAR cannot be left exposed and will need to be covered by a 15-minute thermal barrier such as drywall. If being used for crafts, acrylic or latex based paints can be used with FOAMULAR products. FOAMULAR is available in two edge configurations. Square edge – designed to fit flush next to adjoining boards. Scored Square Edge – comes with 3 factory scores, so that you can take a 4 ft. sheet, break it in two and have two, 2 in. wide sheets (middle score) or you can break it into three 16 in. wide pieces by snapping at the left and right score.