Case Study #2
POLYISO OUTPERFORMS THE COMPETITION IN THREE-CITY,
CANADIAN ROOF INSULATION STUDY
Polyiso insulation decisively outperformed extruded and expanded polystyrenes in a recent commercial roofing study that compared the cost benefits of using various insulation products in Canadian office buildings. The study, conducted by Energy Conservation Management - an independent energy research and analysis firm in Baltimore, Maryland - showed that polyiso yields higher returns on investment, quicker payback rates and lower installation costs than its competitors. Like in many U.S. cities, polyiso’s performance characteristics make it an excellent choice for cost effectively achieving a high level of green construction. The bottom-line numbers featured in this report show why polyiso has become the premier choice for builders in Canada and why it is the leading product in the North American marketplace. As you review the following information, take note of how well polyiso performed in Ottawa, Winnipeg and Toronto and consider how it could improve your profitability!
The Study
Six, single-story buildings were modeled in the three cities (two in each city). Using an hourly energy simulation program called micro-AXCESS 10.2 D, analyses were performed to determine the energy usage and cost of each building. In sets of three, models were created for each weather site:
The baseline roof construction in all cases consists of a built-up roof over 25.4 mm perlite on a steel deck. The baseline building was used solely as a reference point from which to evaluate the other models. For the polystyrene model cases, the roof consists of built-up roof over 12.7 mm vegetable fiber cover board, varying amounts of expanded or extruded polystyrene (depending on the site), and 12.7 mm exterior grade gypsum board underlayment over a steel deck. For the polyisocyanurate cases, the roof consists of built-up roof over 12.7 mm vegetable fiber cover board and varying amounts of polyisocyanurate (depending on the site) on a steel deck.
"POLYISO is in and of itself a good investment because the percentage of investment one can recoup over a given period of time with Polyiso is much higher than with extruded or expanded polystyrenes."
Utility costs were then compared with the installation cost of the polyiso and the polystyrene to determine payback rates and return on investments. The cost ratios were obtained by comparing the labor and materials cost of installing the polyiso with the labor and materials cost of installing polystyrene at the same R-value.
The Results
According to the ECM, in all cases, the underlayment needed when using polystyrene and the increased thickness of insulation needed due to the lower R-value per thickness of polystyrene resulted in higher material and labor cost.
The installation cost ratios for polyiso ranged from 54 to 67 percent, which means that: the cost of increasing insulation from the baseline to a certain R-value was 33 to 46 percent less expensive with polyiso than with polystyrene.
The return on investment (ROI) for polyiso was anywhere from 3.19 to 2.40 times better than extruded polystyrene, and 2 to 3 times better than expanded polystyrene.
The payback rates for polyiso were all at least two to three times quicker than those for polystyrene. According to ECM’s report, “polyiso was shown to be a more profitable investment over polystyrene in all three cities and for all R-values investigated.”
Cost Factors Defined
"The installation costs for increasing the R-value of a roof scenario using Polyiso insulation was less expensive than using polystyrene to
achieve the same R-value. There are higher material and labor costs due to the underlayment and cover board needed when using polystyrene
and the increased thickness of insulation needed to achieve a certain R-value because of the lower 'R per inch' value of polystyrene."
*All figures are based on Canadian currency.
The Polyisocyanurate Insulation Manufacturers Association (PIMA) produces technical bulletins in an effort to address frequently asked questions about polyiso insulation. PIMA's technical bulletins are published to help expand the knowledge of specifiers and contractors and to build consensus on the performance characteristics of polyiso. Individual companies should be consulted for specifics about their respective products.
The Polyisocyanurate Insulation Manufacturers Association (PIMA) is the North American trade association that advances the use of polyisocyanurate (polyiso) insulation. Polyiso is one of the nation's most widely used and cost-effective insulation products available.
PIMA's membership consists of manufacturers of polyiso insulation and suppliers to the industry. Our members account for a majority of all of the polyiso produced in North America.