Johns Manville JM Expand-O-Flash EJ/WC 6 in. x 24 in. Curb Mounted Expansion Joint Cover

The Johns Manville Expand-O-Flash style EJ/WC is a flexible, weather-proof expansion joint cover for curb-mounted applications, offered in a 6 in. x 24 in. size and sold by linear foot. A flexible rubber membrane supported by closed-cell foam forms the bellows, and the membrane extends to form a curb cover that delivers a watertight curb in one easy step. Pair with factory-fabricated intersections where joints cross or change direction.

Key Features:

• Multidirectional movement: Accommodates multidirectional movement across the expansion joint.
• Flexible bellows: Non-reinforced bellows combine a flexible rubber membrane with closed-cell foam support for geometric and elastomeric movement.
• Watertight curb: The bellows membrane extends to form a curb cover, providing a watertight curb in one easy step.
• Weather-proof closure: A flexible, weather-proof exterior cover for expansion joint openings.
• Factory intersections: Labor-saving factory crafted intersections fit most needs, or can be custom designed for special needs.
• Consistent quality: Close factory tolerance and quality control assure high yield performance.

Specifications Table:

Coverage & How Much You Need:

Sold by the linear foot, so order the total run length of the curb expansion joint, and plan intersections where the joint crosses or changes direction.

Fit and Compatibility:

Part of the Johns Manville Expand-O-Flash expansion joint cover line, designed for a wide variety of standard and special commercial roofing applications. Factory-fabricated intersections are available to match where joints intersect, cross or change direction.

Frequently Asked Questions (FAQ):

Q: What size is this cover?
A: The EJ/WC curb mounted style is offered in a 6 in. x 24 in. size, sold by the linear foot.

Q: What is it made of?
A: A flexible rubber membrane supported by closed-cell foam that forms flexible bellows, with the membrane extending into a curb cover.

Q: How does it handle movement?
A: The non-reinforced bellows accommodate multidirectional, geometric and elastomeric movement.

Q: How does it create a watertight curb?
A: The membrane from the bellows extends to form a curb cover, providing a watertight curb in one easy step.

Q: What do I do where joints change direction?
A: Use labor-saving factory crafted intersections, which are made for maximum flexibility and clean, watertight seam lines.

Q: How do I order it?
A: It is sold by the linear foot, so measure the full run of the expansion joint and order that length.

Expert Verdict — Reviewed by the SuperArbor Pro Desk

The EJ/WC curb-mounted style saves the most time where a roof expansion joint runs across a curb, because the bellows membrane continues into a curb cover in one piece. Order factory-fabricated intersections wherever the joint crosses or turns; field-made corners are where expansion joint covers most often leak. Measure the joint opening before ordering so the bellows depth matches the specified joint width.

Install expansion joint covers per the roof system manufacturer's details and confirm the roof deck and curb framing are complete before covering.

Order JM Expand-O-Flash EJ/WC curb mounted expansion joint cover by the linear foot today.