Application of roofing assembly:
The crew installed poly vapour barrier directly over the steel decking substrate and caulked with an acoustical sealant. The insulation of 2.5” Poly iso is then installed in two layers on top of the vapour barrier. The insulation coverboard ½” high density ISO is then installed in one layer over the two layers of installed insulation.
Once the insulation and coverboards are installed, they are screwed down with 7” fastener and a special Invisaweld plate. Fathering rates for 4×8 sheet of cover board is 6 per sheet. The pattern is beefed up around the perimeter to 10 fasteners per 4×8 sheet 10’ for edge around the entire perimeter of the building.
After the insulation and coverboards have been secured with fasteners and plates to the steel deck, the .060 mil TPO membrane (12x 100 rolls) is rolled out over the top. When the membrane is rolled out and laid flat, it is secured to the plates and fasteners below using heat induction welding. The bottom side of the membrane is welded to the top of the top of the fastener and plate. This creates an Invisaweld system.
How big is a million sq. ft.? Here are some numbers to put this into perspective:
• The building is about 1,800’ long by 600’ wide. 1,800’ means you could drag race a car down a drag strip for a quarter mile (1,320’) and still have
500’ to slow down
• It would take Tiger Woods two long plus drives of 300 yards to reach the end of the building.
• The entire perimeter of the building is just shy of one mile or 1.5 km which means 1.5 kilometres
of metal flashing will be installed
• 390,000+ screws and plates will be used to secure insulation to the steel deck. At 5 seconds per
screw this equates to approx. 550 man hours (or one man working 40 hour weeks for 3.5 months to
• 130 trucks (52’ long) of just insulation required or a total of 3,350 4×8 bundles
• 900 rolls of 12×100 .060 mil TPO membrane
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