A study was conducted to provide data on which to base a corrosiveness test for the thermal insulating materials used in residential structures. Several possible test methods were compared. The materials tested included celluloses containing several different fire-retardant additives, glass fiber, rock wool, and a urea formaldehyde foam. Because of their widely differing physical properties, testing was conducted in water leachants made from the insulations. In addition, a test was performed that simulated the condensation conditions that might occur in a residence. It was found that two leachant-based methods could be suitable for accelerated corrosiveness testing of thermal insulation. One method involved determining the corrosion rate of metal coupons immersed in leachant for 14 days at 45°C. The other test was cyclic potentiodynamic voltammetry, which can be completed in only a few hours.