SBS 11.3.2.2-1 Cast Iron Drains

1 WORK INCLUDED

(1) Gypsum Deck Overlay

If required by design authority.

(2) Vapour Retarder

If required by design authority.

(3) Insulation

Mechanically fastened. See available insulation products in the Accepted Materials section of this Manual.

(4) Insulation Overlay Board

Asphalt adhered or mechanically fastened. Two layers required over heat-sensitive insulation.

(5) Primary Membrane and Membrane Protection

(6) Mastic

As approved by manufacturer.

(7) Base Sheet Flashing

As approved by membrane manufacturer (See (C) below).

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2 RELATED WORK BY OTHERS

(A) Acceptable Deck

(B) Roof Drain Assembly

(C) Lead Flashing

Minimum 15 kg / m² (3 lb / ft²) weight lead sheet; flange extending minimum 25 mm (1") into bowl to 150 mm (6") beyond perimeter of drain; embed in mastic (6) and prime top surface where required by manufacturer or minimum 1 m x 1 m (39" x 39") 3 mm thick modified bituminous base sheet; to be supplied by trade supplying roof drain. For asphalt and gravel built-up systems only.

NOTE: Refer to RoofStar Guarantee Standards for additional requirements.

• Leader size is determined by using the calculation found in the BC Building Code at Appendix P.7.4.10 and Section 7.4.10.11 (Section 7.4.10.10 for gutters)(current edition) in conjunction with the 15-minute rainfall value from the National Building Code, Appendix C.

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