Dg Exhaust Insulation Services Involve The Use Of Thermal Insulators To Reduce Heat Transmission Between Spaces, Such As Between The Interior And Exterior Of A Home, Or Between Spaces Within The Same Home. Thermal Insulators Are Materials With Very Low Thermal Conductivity, Such As Wool, Fiberglass, Rock Wool, Polystyrene, Polyurethane, And Goose Feather, prices are not fixed.