Compression is a function of the total weight load of the object divided by the square inches the load is spread over. So, while a horse applies only 25 psi, a woman standing in a stiletto heel of ¼ sq inch can apply 471 psi.

Impact: InsulHeat is laminated with .020 aluminum sheet metal. This surface can withstand the normal impacts of construction and floor use. If  extremely high impact accident occurs, the resulting dent or gouge can be filled with readily available leveling compound.

From a practical standpoint, a radiant designer should apply cement backboard over areas where extreme impact and compression conditions can be expected.

Note: Home center and lumber yards usually have inexpensive 10 psi foam board for use in walls and ceiling and sometimes 25 psi foam. These products can provide adequate support under slabs, however these lower density foam products are not recommended for underlayment assemblies

InsulHeat Exposed: InsulHeat is designed for interior use only. InsulHeat will easily withstand the traffic associated with normal construction. If left exposed to rain during construction plastic should be applied temporarily. InsulHeat is not, like Gypsum cement, designed as a finished flooring surface. See Finished flooring guide. Link.

InsulHeat Cement Backer Board Assembly: InsulHeat covered with Cement Backer Board offers a large increase in compression and impact resistance as well as being an industry approved surface for a number of finished flooring goods including tile. The use of cement boards are commonly used over InsulHeat in garage applications where higher compression loads are experienced and then covered with epoxy coating for oil, solvent and water resistance. Backerboard is not required over InsulHeat for many types of finished flooring goods.