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:~`~~_~. ~~~ :~ .~_ ~COItiiSTRU Oltii ~~~ Metal Roofs Score Best in Com arative Anal sis p y Of roof life expectancy, life material failure. By comparison, 30% of the built-up roofs and 56% of the CyC~e COStS~ rYldlClte'11dnCe OUtIayS resglt pl iromfmateral falu e~eaks g Metal roofs have a significantly longer expected service life than either built-up roofing or single-ply roofs, according to a 2004 study of low slope roofing conducted by Ducker International, aDetroit-based research organization that specializes in construction materials. Study participants said they expected metal roofs to last 40 years-17 years longer than built-up and 20 years longer than single-ply systems. At the same time, respondents to the Ducker study said they expected Fife cycle costs of a metal roof, including outlays for maintenance, to be about 30 cents a sq. ft. per year, significantly less than the 37 cents for built-up roofs and 57 cents for single-ply roofs. Expected Service Life 40 years ea y , rs 20 years Metal Built-up Single-ply Service life and life cycle costs were the two most important of 10 criteria considered when purchasing a roof system, respondents said. On a scale of one to five (with five representing an extremely important consideration), service life rated a 4.8 and life cycle costa 4.6. Little Or No Maintenance Required For Metal Roofs The expected low life cycle cost of a metal roof can be attributed, at least in part, to the fact that the owners and managers surveyed reported having to perform little or no regular maintenance to their metal roofs. Consequently, owners of metal roofs said they spent less than 4% of the total installed cost on maintenance compared to 29% by owners of built-up roofs and 19% by owners of single-ply roofs. Expected Life Cycle Costs Metal Built-up Single-ply The life cycle cost of a roof is determined by computing the present value of all cost associated with the roof over its life, including annual maintenance costs. The Ducker analysis also factored in an annual inflation rate of 3.1 %. The study further confirmed that life cycle costs for metal roofs, unlike those for built-up and single-ply, are consistent across all major commercial construction categories, including office, retail, institutional and industrial. Not reflected in the analysis are potential energy cost savings resulting from the use of a reflective roof system wish adequate insulation. These savings could lower the expected life cycle cost of a metal roof by an additional 8 to 10 cents per sq. ft., depending upon the region of the country, building function and insulation thickness. Among the more intriguing findings is that many of the roofs in the study experienced leaks, but none of the metal roofs leaked as a result of No Leaks !n Metal Roofs Due To Material Failure The roofs analyzed by Ducker had, for the most part, been in service for more than 10 years at the time of the study and had an average size of 92,000 sq, ft. Typical metal roofs analyzed were 24 gauge standing seam roofs that used standard fasteners and a PVDF coating, while built-up roofs were typically 3-4 ply and single-ply roofs were made of 45 mil, non reinforced membrane. The performance record of metal roofs examined prompted owners and property managers of these roofs to report the highest level of satisfaction with the"value for price paid." On a scale of one to five (with five representing the highest rating), metal scored a 4.75 compared to 4.30 for built-up and 3.91 for single-ply. In line with the owner/manager satisfaction rating, metal roofs also topped the field in terms of customer loyalty. When asked if they would use the same roofing material in the future, 92% of the metal roof owners surveyed said they would, compared to 46% of the built-up owners and 58% of the single-ply owners, Maintenance Percent of roof leaks es result of material tailure 309~b 0% Metal Built-up Single-ply For additiona! information on the fife cycle cost analysis, visiq~~j' Initiative website at therr~~{ij{~,jiy~,~lg~l2 Page 160 of 199