ESCSI INFORMATION SHEET 3530 - MARCH 2000

Life Cycle Energy Cost Analysis
Shows That SmartWall Systems Provides Significant Savings in All Climates

SmartWall Systems is a concrete masonry wall system that outperforms other masonry and non-masonry wall systems. SmartWall Systems offers superior performance, especially in terms of energy efficiency, maintenance, appearance, fire resistance, durability, and strength to weight ratio.

The built-in thermal resistance and low thermal bridging of SmartWall Systems saves energy in both warm and cold climates.

The Life Cycle Cost analysis illustrated in the graph uses local climate data and energy costs for heating and cooling, and show the significant life cycle energy cost savings achieved by SmartWall Systems. In many cases the present value of these savings will pay for the SmartWall System itself. For example, the analysis shows that a SmartWall building in Omaha saves $1.15 per block over the first ten years of the building’s life, and $2.86 over a thirty-year period.

The analysis compares SmartWall Systems concrete masonry units at 90 lb/ft³ density to ordinary 135 lb/ft³ units. Units are standard 8" x 8" x 16" dimensions. The analysis uses steady-state heat flow calculations.

Detailed information on the thermal values, energy costs and the methodology of the Life Cycle Costing analysis illustrated above is shown on the following pages. For more information about SmartWall Systems, contact the Expanded, Shale, Clay, and Slate Institute office or any ESCSI member.

Table 1:
Life Cycle Energy Cost Analysis Present Value of Annual Energy Cost Savings Using SmartWall Systems Over a Thirty Year Period

Wall construction: Single wythe 8" w/foamed in place core insulation
Location: Omaha, Nebraska

Table 2:
Life Cycle Energy Cost Savings by City for Ten and Thirty Year Periods with Climate and Energy Costs

References for Table 1 and Table 2:

(1) Appendix A, Climatic Data for the US and Canada, ASHRAE 90.2, 1993.

(2) Natural Gas Costs: Natural Gas Monthly, US Department of Energy – Energy Information Administration, October, 1999. Table 22, page 57-59. Commercial gas costs by state were used for the most recent complete year available. Contact ESCSI for details.

Electricity Cost: Electric Sales and Revenue 1998, US Department of Energy – Energy Information Administration, October 1999, Table 15. Commercial Average Rates for the Utility serving the selected city.

(3) R-values for Single Wythe Concrete Masonry Walls, TEK 6-2A, National Concrete Masonry Association, 1996. The R-value is interpolated for 90 pcf. Values are for unreinforced walls. For walls with 32" o/c vertical grouting and reinforcing, the difference in U values between a 90 lb/ft³ wall and 135 lb/ft³ wall drops to 0.153, a 2.5% reduction. Life cycle savings will be reduced by a similar amount. Calculation procedures for grouted walls are shown in the
referenced NCMA TEK.

(4) The 2% nominal discount rate was chosen as appropriate for this analysis because it represents the typical long-term two percent difference between short-term US T-bill rates and the CPI inflation rate. See Office of Management and Budget Circular A-94 Guidelines and Discount Rates for Benefit-Cost Analysis of Federal Programs.

This analysis was developed by Buildex Inc. for use with permission by members of the Expanded Shale, Clay, and Slate Institute, Salt Lake City, Utah and is © 2000 ESCSI. This March 2000 edition replaces earlier versions of this publication, which used different furnace efficiencies and cooling SEER and a less comprehensive source of commercial electricity costs.

ESCSI INFORMATION SHEET 3530 - MARCH 2000