Most northern latitude metal contractors were extremely challenged during the 2010-11 winter in getting their projects started. A great example of this is Pat Munger Construction, Inc. of Branford, CT. where they had to dig out of the more than normal snowfall to start a retrofit re-roofing project. Case in point is a project for Ocean Surveys, Inc. – a scientific data firm - located in Old Saybrook, CT just one-mile from Long Island Sound.
In mid-December 2010, the Munger Construction team was ready to begin a very unique 14,300 square foot reroof project only to be blasted by "Old Man Winter", postponing their start for a few months. According to Steve Mansfield, Vice-President of Estimating & Sales, before anyone knew it, they were covered with forty plus inches of snowfall all within a week's time - with sleet, ice and freezing rain thrown in to boot. Needless to say, the job was held-up until it was safe to re-mobilize in early March. Michael Cormier was the on-site job superintendent for Munger, which completed the project during the same month. The entire retrofit and new metal roof was installed by erector First Choice Builders of Terryville, CT.
The project was not a normal retrofit reroof as most are. This project was much more complicated due to a slope transition midway up the roof, caused by two metal buildings joining sidewall to sidewall. Roof Hugger, Inc. of Lutz, Florida was called in by the design-build team at Munger to help create a retrofit sub-framing system that would eliminate the slope transition. To accomplish this issue, varying depth Hugger sub-purlins were provided near the point of the roof transition.
In addition and to further complicate the project, Munger chose to install a new VP Buildings' “Panel Rib” thru-fastened metal roof, which is not designed to accommodate thermally induced stresses. On smaller building roofs this would not be an issue, but the overall panel run from eave-to-ridge on this project was 150 feet causing the concern. To help with this issue, Roof Hugger came to the rescue again by suggesting their patented “Roof Floater™” sub-framing system. Dale Nelson, President of Roof Hugger® stated that this system enables any screw-down or thru-fastened roof system to be thermally active due to the unique design of the Floater’s base clip.
The system essentially creates a monolithic roof with sub-purlins that expand/contract with the new roof, independent of the Roof Floater base clips. The clips provide 3 inches of total movement, which accommodates eave-to-ridge panel runs over 200 feet. He added that the Roof Floater system is not exclusive to new thru-fastened metal roofs but can also be employed in fiberglass reinforced panel (FRP) and aluminum roofs due to their excessive thermal expansion characteristics as well insulated metal panels (IMP) systems having similar characteristics in exceptionally long panel runs.
For this project, the new VP metal roof was “pinned” near its center area using standard Huggers that varied from 3 to 5 1/2 inches in depth. Then, above and below the pinned area, 1-1/8 inch deep hat-shaped purlins were installed on to 1-5/8 inch deep Floater base clips. The overall Floater system assembly was 2-3/4 inch deep, which accommodated 3-inch deep fiberglass insulation being installed between the old and new metal roofs. Ocean Surveys, Inc. will definitely appreciate this thermal resistance upgrade in the cold harsh winters to come.
Metal-over-metal retrofit re-roofing is a vast market with thousands of successful installations representing millions of square feet. Nowadays, re-roofing technology can provide the building owner the ability to upgrade to “Next Generation” metal roofs that include energy efficient ventilated and insulation roof assemblies as well as installing solar thermal hot water and hot air recovery systems with renewable energy photovoltaics atop the new metal roof. For those building owners located in coastal area, it is now possible to update the building roof to meet current specified wind velocities upwards toward 150 miles per hour.
For more information on metal-over-metal retrofit re-roofing using Roof Huggers® and Roof Floaters™, contact Roof Hugger at 800-771-1711 or visit www.roofhugger.com. For more about Pat Munger Construction, Inc., go to www.mungerconstruction.com.
For more information about metal roofing from VP Buildings, visit www.vp.com.