EPS), where concrete is poured into the cores. They come in different configurations, use different connectors, and achieve varying R-values. Some of the forms may not directly reduce concrete use, but they definitely increase its thermal efficiency and longevity . Finally, although a comprehensive discussion of the impact of land use planning on materials consumption is beyond the scope of this dissertation, our discussion of concrete reduction strategies must at least mention that a green economy means many fewer highways. A shift away from large loops of production and consumption requires more compact development patterns with mixed commercial, residential and even industrial uses. About 40 percent of the surface area of North American cities is currently highways, parking lots, etc., and much of this area can and must be taken over by green space. This means both a drastic reduction in concrete and asphalt use, as well as the substitution of new kinds of porous paving (Environmenal Building News, 1999).