WFE-1 (LB). CSI 3-Part Specifications.

	BITUMINOUS FLASHINGS
	Specification WFE-1 (LB)

For use over load bearing masonry constructions

General

This specification is for use on non-nailable surfaces where the deck is supported by a masonry wall.

Note: All general instructions contained in the current JM Commercial/Industrial Roofing Systems Manual shall be considered part of this specification.

Wall Preparation: Any previously installed metal cap or counter flashing must be raised or removed to permit application of the base flashing.

Apply Johns Manville (JM) Concrete Primer to the masonry wall to the full height of the proposed base flashing and allow it to dry thoroughly.

Materials

TRICOR M FR, TRICOR S, BICOR S, APPeX 5S, APPeX 4S, APPeX 180, APPeX 4.5M FR, APPeX 4.5M, APPeX 4M, APPeX Black Bear, JM APP Base or JM Concrete Primer.

Application

Base Flashing: The roof membrane must extend to the top of the cant. Cut a strip of APPeX 5S, APPeX 4S, APPeX 180, or JM APP Base for use as a backer felt. The material should be cut such that when installed it will be 1 to 2 inches (25 to 51 mm) below the top ply of the base flashing system and terminates at the bottom of the cant. Starting at the base of the cant, heat weld the backer felt up the cant onto the vertical surface, to a point just below the point where the top ply of the base flashing will terminate. Do not extend the backer felt beyond the base of the cant onto the roof surface. The backer felt should not project onto the roof membrane.

Over the backer felt, install a layer of TRICOR M FR, TRICOR S, BICOR S, APPeX 5S, APPeX 4S, APPeX 180, APPeX 4.5 M FR, APPeX 4.5 M, APPeX 4M or APPeX Black Bear. This material should extend not less than 8" (203 mm) and not more than 24" (610 mm) on the vertical surface of the parapet. The flashing sheet should project onto the roof membrane not less than 4" (102 mm).

Heat weld the flashing and backer felt so that they are firmly and uniformly set. All laps must be rolled with a 3" (76 mm) rounded edge roller. A minimum 1/8" to 3/8" (3 mm to 10 mm) bleedout of APP compound shall be visible at the edge of all laps. If the compound bleedout is not accomplished, heat a trowel with a propane flame, lift the lap, apply a flame to both sides of the lap area and smooth the melted compound with the trowel to form an even seal.

Base flashing systems using TRICOR S, BICOR S, APPeX 5S, APPeX 4S, or APPeX 180 as the top ply must be coated with TopGard Type A or with TopGard Type B which then may be surfaced with Fibrated Aluminum Roof Coating. Systems using a granulated surfaced product as the top ply do not require additional surface treatments.

Metal Counterflashing: When used, it should be installed according to the manufacturer’s specifications, overlapping the base flashing by at least 4" (102 mm).

Caution: Improper use of these materials and application equipment can result in severe burns, and/or damage to property. The mechanic must install these materials using the techniques recommended by JM and those found in "A Guide to Safety: Torch-On Modified Bitumens" available from the Asphalt Roofing Manufacturers Association.

For an identical copy of this specification, ask for RS-4322.