Roof Insulations - Page 25

	Roof Insulations
	Specification 1M One Layer Mechanically Attached

Mechanically Attached

Apply the units of approved JM roof insulation with long joints continuous. End joints should be staggered so that they are offset at least 12" (305 mm) from the end joints in adjacent rows. If insulation is being installed over an existing layer of insulation, all joints in the insulation layers must be offset a minimum of 6" (152 mm) between layers. Insulation boards should be tightly butted with adjacent boards. Insulation joints greater than ½" should be properly filled to receive the subsequent layers of the roofing system. Use an approved mechanical fastener of sufficient length to penetrate through or into the deck as required by the specific fastener. Fasteners should be placed in the pattern for the approval desired but never closer than 6" (152 mm) from either edge of the insulation board. On steel decks, the edges of the insulation board that runs parallel to the deck rib must be solidly supported by the ribs. Fasteners are to be driven through the appropriate insulation plates. Care should be taken not to overdrive or underdrive the fastener. Overdriving the fastener will cause the insulation plate to "cup" and can result in inadequate performance and damage to the membrane. Underdriving can cause the insulation to be loose from the deck and allow the fastener to penetrate into the membrane.

Apply only as much insulation as can be covered by a complete roof membrane in the same day. Do not leave insulation exposed to the weather.