Abstract: In a metal reheating furnace, a resilient, vibration resistant and easily installed thermal insulative structure is defined by an inner batt of refractory fibers held in place by an outer wrapping of woven refractory fibers and so arranged as to be self-retaining. This relatively soft, resilient structure supports an outer shell of refractory mortar which adheres to but does not substantially penetrate the woven wrapping, such that vibration and mechanical shock are absorbed in the soft insulation while the exterior layer protects against molten slag and high speed impinging gas flows.