Division 7 Ebook Page 435 FOAMULAR Tapered Roof Insulation, 07 22 16

FOAMULAR DURAPINK , Recover Roof Insulation D. All existing roof structures over which roof board insulation is to be applied shall be evaluated for the necessary structural dead load carrying capacity to accommodate the minimal additional dead load of the recover roofing system. The entire recover roofing system including roof board insulation, possible a separator sheet and single-ply membrane, is not likely to weigh more than 1.0 psf. E. [Place an impervious separator sheet, such as 6 mil polyethylene, between coal-tar BUR and roof board insulation.] This is required only if the existing coal-tar BUR is less than ten years old in a northern environment or less than seven years old in a southern environment, or has been re-saturated or patched in the last four years. F. Any deteriorated roof decking shall be repaired or replaced before installing the recover roofing system. G. Verify that existing roof drains are adequate, open and are properly functioning before installing the recover roofing system. EXISTING VAPOR RETARDER A. [Existing vapor retarder must be perforated at the rate of [_____square inches per square foot].] The presence of an existing vapor retarder may slow the drying rate of a moderately wet recovered roof, making total dry out time longer. See the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) Handbook of Fundamentals for specific design guidelines. INSULATION A. Apply only as much roof insulation as can be covered by the roofing membrane on the same day. B. Apply insulation in parallel rows, perpendicular to membrane seams [if possible.] with end joints staggered. See the note following this paragraph. Install side and end joints closely but do not force together. Some contractors and membrane manufacturers prefer that the long dimension of the insulation board be installed parallel with the membrane seams, thereby avoiding a "sawtooth edge" when preparing overnight seals or beginning the next roll of membrane. Installation perpendicular to membrane seams is only a suggestion to increase the probability of more membrane fasteners crossing any given board. This requirement can be waived if necessary. C. Place the insulation board with the printed logo surface down so that the black lettering is not exposed to potential solar heat gain. D. In areas where black/dark membranes are used and where "reflected solar energy" is expected to be present, the roof board insulation need additonal protection. For example, roof areas adjacent to higher walls, particularly walls with reflective surfaces, or near large rooftop HVAC units, or near or in between clusters of mechanical equipment, or near other structures with reflective cladding (metal or glass); or near higher reflective parapets, all such areas should be considered for additional heat protection. Such roof areas must be covered with pavers or ballast or black/dark (non-white) membranes must be coated with white reflective topping, and maintained white, to avoid damage due to the intensified heat exposure from reflected sun in such areas. E. Insulation joints as installed shall not exceed 1/4" in width. Joints wider than 1/4" shall corrected by filling with like material. F. Insulation shall be field trimmed to fit tightly around roof protrusions and terminations. G. Mechanical fasteners shall be of sufficient number and appropriate pattern to resist wind uplift forces. Fastening patterns shall be as specified for the appropriate system from Table A. ROOF BOARD INSULATION 07 22 16 - 5

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