$54.99 Super TUFF-R 1/2 in. x 4 ft. x 8 ft. R-3.3 Foam Insulation-268413 - The Home Depot
R-5 1-in x 8-ft x 2-ft Faced Polystyrene Foam Board Insulation in the Foam Board Insulation 
Johns Manville CI Max® Polyiso Foam Board Insulation 4' x 8' at Menards®
