Product Review

Rastra-Recycled Polystyrene Foam Forms

The Rastra system uses 100% recycled expanded polystyrene (EPS) foam, ground into small beads and mixed with Portland cement. A proprietary additive helps with the mixing process. Rastra has some intriguing features, but estimates of the pollution associated with its manufacture show that it may not be significantly “greener” than many competing systems.

Like most other foam-form wall systems, Rastra should be quite energy efficient, though the actual R-value of the material won’t be known until independent laboratory tests are completed later this summer. This efficiency, together with the use of recycled EPS, makes Rastra environmentally attractive. Functionally, Rastra has a big advantage over most other foam form systems in that the cement prevents insect infestations. Although insects don’t eat polystyrene, they often nest in it and can be hard to remove.

Published July 1, 1996

(1996, July 1). Rastra-Recycled Polystyrene Foam Forms. Retrieved from