COLUMN BUILDING SCIENCES FIGURE 6 Crawl Spaces Insulated on the Interior. Don't forget the inspection gap. This is a requirement in many, many jurisdictions. It is a good idea in general. Carbondale, Colo., in 2006-where the exterior foundation insulation is protected by rigid metal sheeting installed directly over the insulation. The design credit goes to architect Steve Novy. What else works well? Cellular PVC. Check out the detail in Figure 7, a shallow frost-protected foundation that has the rigid horizontal insulation protected by a concrete " skirt " as well as a fully adhered membrane and a strip of aluminum or alternatively a strip of cellular PVC (Photo 7, Photo 8 and Photo 9). So, where are we after all of these years? Stucco works-just be careful. Fully adhered membrane strips work. Aluminum sheets work. Fibercement and cement board sheets work-just follow the manufacturer's installation instructions. Note that not all manufacturer's recommend their products for this application. Cellular PVC works. Lots of options. Just remember to absolutely, positively deal with the insect pathways. Did I mention the insect pathways? Insects can be a pest. FIGURE 7 Shallow Frost Protected Foundation. Rigid horizontal insulation protected by a concrete " skirt " as well as a fully adhered membrane and a strip of aluminum or alternatively a strip of cellular PVC. 38 ASHRAE JOURNAL ashrae.o rg M AY 2023http://www.ashrae.org