To prevent the degradation of exterior foundation insulation from backhoes, ultraviolet radiation, and kids' bikes, rigid foam should be covered above grade. Two products, Polyskirt (Plymouth Foam Products) and Retro-Tek (Retro Technologies), provide alternatives to real stucco or pressure-treated plywood. Polyskirt is a rigid foam insulation panel covered with a plastic laminate. The plastic – polyolefin – can be cut with a utility knife and reportedly expands less than vinyl Based on a sample we saw, the panels seem strong enough to withstand a modest bump from a lawnmower but a fast baseball would probably break the surface. In freezing temperatures, it seems even more brittle. Joints between panels are covered by a plastic I-channel (a noticeable improvement to T-moldings used with