SECTION 7 : APPENDICES

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1 SECTION 7 : APPENDICES APPENDIX A: Life Cycle Cost Analysis The following life cycle cost analysis for EIFS and precast concrete panels is based on methods and factors provided by ASTM Standard Practice for Measuring Life Cycle Costs of Buildings and Building Systems. Assumptions: Cladding - Typical three story commercial office building ft x 200 ft footprint - Non-load bearing exterior walls - Wall surface area 23,000 SF Structural - Estimated costs do not include connection hardware. - Floor-to-floor 10 ft, typical for commercial building Cost/Data - Estimated installation costs do not include related equipment rental costs. - Estimated installation costs of the cladding and structural framing assembly shown in Table A were derived from R.S. Means Assemblies Cost Data Estimated maintenance costs & frequencies were derived from R.S. Means Facilities Maintenance and Repair Cost Data 2003 and reference material. - Construction began July 2001; cost estimates are adjusted from 2003 data to 2001 at a cost index of 96.1 percent. Life Cycle Cost - Total life cycle costs, Table B, are calculated in present terms - Assumes 30 year study period - Projected annual discount 4 ¾% - Inflation rates 3% 36 Senior Thesis Report

2 TABLE A - Cost Data (Current Dollar Costs)* Estimated Description of Initial Maintenance Installation Costs Cladding and Structural Framing Assembly Exterior Insulation and Finish Systems (Class PB) with metal stud framing Precast Concrete panels with metal stud framing (non-load bearing) $ 344,761 ($15.00/ft 2 ) $ 275,377 ($12.00/ft 2 ) Clean 100% of the EIFS Clean and recoat 100% of the EIFS Recaulk 100% of the panels General cleaning 100% of panels Maintenance Costs and Frequencies $ 9,421 at year 15 $ 18,432 at year 30 $ 30,925 at year 20 $ 9,421 at year 25 * For calculation of Initial Installation Costs see Assembly Descriptions & Installation Calculations on page 22 & 23. TABLE B Projected Life Cycle Cost (Present Value Dollars)** Cladding and Structural Framing Assembly Estimated Installation & Maintenance Costs (Year) Total Life Cycle Cost EIFS (Class PB) cash outflow (initial costs and maintenance) 344,761 7, ,119 $ 363,198 Precast Concrete cash outflow (initial costs and maintenance) 275, ,079 6,183 0 $ 303,639 ** For calculation of Present Value Dollars see Life Cycle Cost Equations on page Senior Thesis Report

3 Assembly Descriptions & Installation Calculations EIFS TABLE C: System Components EIFS Exterior Insulation and Finish System (EIFS, Class PB) System Components Cost per square foot ($) Fiberglass batt insulation, 6 in. thick, 15 in. wide 0.60 EIFS Framing, 6 in. metal 16 o.c. Cement board sheathing, ¾ in. 4 Expanded polystyrene insulation board (EPS) EIFS base coat Reinforcing mesh Finish coat Total unadjusted present value cost = $ Assembly Specifics Framing = 6 in. metal studs, non-loadbearing, galvanized, 25 gauge, 16 in. on center Cavity Insulation = 6 fiberglass batt, R-19 EPS thickness = 4 in. R Value Calculations EPS insulation board provides an R value of 5.0 per inch, a total R value of 20. Fiberglass batt insulation value will not be considered in R value calculations due to the fact that the framing and insulation assembly is consistent through both systems being analyzed. Installation Cost Cost/square foot = $ Total installation cost = cost/square foot x wall area = ($16.35/ft 2 ) x (23,000 ft 2 ) = $ 376,050 Location Adjustment Location factor for State College, PA = 95.4 percent. ($376,050) x (95.4/100) = $ 358,752 Time Adjustment 2003 data to construction start of July 2001 cost index = 96.1 percent. ($358,752) x (96.1/100) = $ 344,761 Total Adjusted Installation Cost = $ 344, Senior Thesis Report

4 Assembly Descriptions & Installation Calculations Precast Concrete TABLE D: System Components Precast Concrete Precast Concrete Cost per System Components square foot ($) Metal studs, non-loadbearing 16 o.c Fiberglass batt insulation, 6 in. thick, 15 in. wide 0.60 Flat precast concrete panel Thickness 6 in. thick Panel size (ft) 6 x 18 Finish smooth gray Rigid insulation 2 in. Type low rise Add l 2 in. rigid insulation* 0.73 Total unadjusted present value cost = $ Assembly Specifics Framing = 6 in. metal studs, non-loadbearing, galvanized, 25 gauge, 16 in. on center Cavity Insulation = 6 fiberglass batt Precast concrete panel = 6 ft x 18 ft, 6 inch thick, R-10 (includes 2 in. rigid insulation) Sealant is used around the perimeter of all precast concrete panels; cost will be added to the total. Backer rod, polyethylene, ½ in. diameter = $ 0.59 / lf Polyurethane, bulk in place ¼ x ¼ = $ 1.88 / lf Sealant & Backer Rod: $0.59/lf + $1.88/lf = $ 2.47/linear ft R Value Calculations Precast concrete panel and 2 in. rigid insulation provide an R-10. Fiberglass batt insulation value will not be considered in R value calculations due to the fact that the framing and insulation assembly is consistent through both systems being analyzed. * In order to match R-20 set by the EIFS, an additional R-10 must be added to the assembly. An addition of 2 inches of EPS insulation will increase the R value by 10 and achieve the desired total R-20. Installation Cost Cost/square foot = $ 12.63/sf Sealant & backer rod = $ 2.47/lf Total installation cost = cost/square foot x wall area + cost/foot x length = ($12.63/ft 2 ) x (23,000 ft 2 ) + ($2.47/ft) x (4,000 ft) = $ 300,370 Location Adjustment: location factor for State College, PA = 95.4 percent. ($300,370) x (95.4/100) = $ 286,553 Time adjustment: 2003 data to construction start of July 2001 cost index = 96.1 percent. ($286,553) x (96.1/100) = $ 275,377 Total Adjusted Installation Cost = $ 275, Senior Thesis Report

5 Life Cycle Cost Equations and Sample Calculations Life cycle costing (LCC) is described by ASTM as follows: ASTM Standard Terminology of Building Economics E A technique of economic evaluation that sums over a given study period the cost of initial investment less resale value, replacements, operations, energy use, and maintenance and repair of an investment decision. The costs are expressed in either lump sum present value terms or in equivalent uniform annual values. Analysis of life cycle costs for each system will be calculated on this basis as outlined in R.S. Means Company, Inc., Facilities Maintenance and Repair Cost Data Equations used to calculate Estimated Installation & Maintenance Costs in Table B. Total cash outflow is equal to the initial installation cost of the cladding plus the present value amount at each scheduled maintenance period. The following formulas were used to compute the above calculation: Future value of current dollars: where Present value of future dollars: F = future value of current dollars P = present value of $1.00 r F = interest rate of inflation (3%) r P = discount rate (4 ¾%) n = number of periods (years) Sample calculations to compute the total Cash Outflow for EIFS from Table B: At 0 years (initial cost) P = $344,761 At 15 years = $ 9421 ( ) 15 = $ 14,678 At 30 years = $ 18,432 ( ) 15 = $ 44,740 = 14,678 ( ) 15 = $ 7,318 = 44,740 ( ) 15 = $ 11,119 Total outflow in present value dollars Calculation of life cycle cost for EIFS yields: Initial cost + P at 15 years + P at 30 years = $344,761 + $7,318 + $11,119 = $ 363,198 Calculation of life cycle cost for precast concrete yields: Initial cost + P at 15 years + P at 30 years = $275,377 + $22,079 + $6,183 = $ 303, Senior Thesis Report