Can you recommend a method of insulating regular 8-inch concrete masonry units that performs as well as an insulated 6-inch wood-frame house and is still cost competitive? Would rigid insulation on the exterior and veneer or lathe and stucco do the trick? I need some statistics to show comparisons. My area is in the White Mountains of Arizona: 7,000 feet elevation, -20º F to +88º F. This may help us get into the housing market in this area.

Following the chart shown here, you can build a concrete masonry wall with an R value equal to the R value of an insulated 6-inch wood-frame wall. Check with your local material suppliers for exact R values and prices of materials. Using molded expanded polystyrene or extruded expanded polystyrene instead of expanded polyurethane would provide R values of 7.00 or 10.00 instead of 12.50.

INSULATION NEEDED TO GIVE 8-INCH CMU WALL SAME R VALUE AS INSULATED 6-INCH WOOD-FRAME WALL
6-inch wood-frame wall R value
1. Outside surface film 0.17
2. Wood siding 0.81
3. Sheathing felt 0.06
4. Plywood sheathing, 1/2 inch 0.62
5. Batt insulation 19.00
6. Gypsum plasterboard, 1/2 inch 0.45
7. Inside surface film 0.68
  Total 21.79
8-inch concrete masonry wall R value
1. Outside surface film 0.17
2. Stucco, 3/4 inch 0.15
3. Lightweight concrete masonry 2.12
4. Cores filled with insulation 4.85
5. Expanded polyurethane rigid insulation, 2-inch 12.50
6. Gypsum plasterboard, 1/2 inch 0.45
7. Inside surface film 0.68
Total 20.92
SourcesMeans, R. S., Building Systems Cost Guide, 100 Construction Plaza, Kingston, MA 02364.Olin, Schmidt, and Lewis, Construction--Principles, Materials and Methods, Institute of Financial Education, 111 E. Wacker Dr., Chicago, IL 60601."Thermal Insulation of Concrete Masonry Walls," NCMA-TEK 38-A, National Concrete Masonry Association, 2302 Horsepen Rd., Herndon, VA 22070.