Roof Insulations - Page 24

Adhered

Firmly set the units of approved JM roof insulation, long joints continuous and short joints staggered, into a full width mopping of hot asphalt (within 25°F [14°C] of the EVT). The asphalt should be applied at a nominal rate of 30 lbs. per square (1.46 kg/m² ). Porous substrates may require greater amounts of asphalt. Concrete decks must be primed with JM Concrete Primer prior to the application of hot asphalt. When adhering insulation with hot asphalt, board size must be no greater than 4' x 4' (1.22 m x 1.22 m). If insulation is being installed over an existing layer of insulation or in multiple layers, all joints must be offset a minimum of 6" (152 mm) between layers. Insulation may not be adhered directly to wood, steel, gypsum, structural wood fiber or lightweight insulating concrete decks. If insulation is adhered over nailed base sheet, the nailing pattern shall be as shown below.

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.

When nailing a base sheet to a nailable deck, JM requires the fastening pattern illustrated below:

The side laps are secured 9" (229 mm) on center, and the center of the sheet is secured with two staggered rows of fasteners 11" (279 mm) apart, fastened 18" (457 mm) on center.

Loose Laid

Insulation units may be loose laid with no means of attachment to the structural deck in SPM Specification SE4B. It is highly recommended that over steel decks, some means of mechanical fastening be used. Install insulation units 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. The units of insulation should fit snugly to adjoining units. If insulation is being installed over an existing layer of insulation or in multiple layers, all joints must be offset a minimum of 6" (152 mm) between layers.

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.

Cold Adhesive

Firmly set the top layer of approved JM roof insulation, long joints continuous and short joints staggered, into JM MBR^® Cold Application Adhesive. The adhesive should be applied at a nominal rate of 2 ½ to 3gallons per square (1.02 to 1.22 liters/m²), with a minimum application rate of 2 gallons per square (0.82 liters/m²). If applied to porous materials, the application rate will increase, depending on the absorbency of the material. Concrete decks must be primed with JM Concrete Primer prior to the application of hot asphalt. If insulation is being installed over an existing layer of insulation or in multiple layers, all joints must be offset a minimum of 6" (152 mm) between layers. Insulation may not be adhered directly to wood, steel, gypsum, structural wood fiber or lightweight insulating concrete decks. If insulation is adhered over nailed base sheet, the nailing pattern shall be as shown in Specification 1A.

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.