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

For use over decks with non-load bearing walls

General

This specification should be used where there is any possibility that differential movement will occur between the deck and vertical surface. The vertical wood member should be fastened to the deck only.

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

Preparation for Flashing: If a two-piece metal cap flashing is installed prior to application of base flashing the flange of the metal cap flashing shall be removed to allow for application of the base flashing materials.

Materials

Johns Manville (JM) 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 Sheet, GlasBase, PermaPly 28 or Ventsulation.

Application

Base Flashing: Prior to starting the roof membrane, install a section of TRICOR S, BICOR S, APPeX 5S, APPeX 4S, APPeX 180, JM APP Base, GlasBase, PermaPly 28 or Ventsulation felt of sufficient width to completely cover the vertical wood member and the cant, with the upper portion of the backer felt wrapped over the top of the curb. Using nails spaced 9" (229 mm) o.c. secure the backer felt through the vertical face of curb just above the top of the cant, leaving the top portion of the backer felt to be secured when the felt envelope is installed.

A felt envelope is constructed by wrapping fibrous glass insulation in an asphalt roofing felt. Nail both edges of the felt and the wrapped edge of the backer felt to the top of the wood curb approximately 12" (305 mm) o.c.

The roof membrane must extend to the top of the cant.

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 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. Expand-O-Flash is to be installed in accordance with JM specifications.

Expand-O-Flash Installation: Install Expand-O-Flash in accordance with the application instructions included with the product. Prefabricated inside and outside corners, as well as horizontal-to-vertical transitions, are available to complete the Expand-O-Flash installation.

Metal Counterflashing: When used, it should be installed according to the manufacturer’s specifications, overlapping the upper edge of the top ply of 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-4325.