At Last, a System for Insulating Slabs

You have to hand it to CertainTeed's R&D division. They pay close attention to the elements of home construction where an innovative product can save time and money. Recently, they've come out with partially recycled insulated vinyl siding. A few years ago they introduced a basement drainage system. And now they've addressed one of the longest standing "missing links" of home insulation--the slab.

The new product is called EnergyEdge. I looked over the specs (available here), and they look pretty straightforward. One thing you'll note right away is that the forms stay in place after the pour. The EnergyEdge is essentially a rigid form solves the age-old problem of how to protect above-grade insulation from the elements. It also saves on form materials. One area for improvement: At present, the outer rail system is made of virgin PVC. A better environmental option would be another polymer that has a high recycled content--and better performance. EPDM "crumb rubber" from tire rubber seems like a natural fit for such a low-profile use.

From their webste: "EnergyEdge rails can be used as the concrete form with a kicker system or as a form liner. EnergyEdge braces should be used as rail connectors, occur within 18" of the joint or corner and 36" on-center thereafter. Rails should be laid corners first and straight runs last- minimizing cutting to the middle rail completing the run. Align, level and mechanically secure the rails to the kickers with screws on the exterior face of the rail. After the concrete has been poured and finished, screws may be backed out of the rails and kickers removed. EnergyEdge products remain in place, leaving a finished and insulated edge."