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Johns Manville Expand-O-Flash EJ Cant-to-Wall/Cant Expansion Joint Cover, Mill Finish, 4 in., 6 in. and 8 in. Sizes
Regular price $645.00Johns Manville Expand-O-Flash EJ Cant-to-Wall/Cant Expansion Joint Cover, Mill Finish, 4 in., 6 in. and 8 in. Sizes
This is the Johns Manville Expand-O-Flash EJ cant-to-wall/cant expansion joint cover, a flexible, weather-proof exterior closure for expansion joint openings in commercial roof assemblies. It combines a flexible rubber bellows membrane supported by closed-cell foam with two metal flanges, and is sold as a roll in 4 in., 6 in., or 8 in. widths in mill finish. It pairs with JM low-slope roof systems at cant-to-wall and cant-to-cant conditions.
Key Features:
- Multidirectional movement: Accommodates multidirectional movement as the expansion joint flexes over time.
- Flexible bellows design: Non-reinforced bellows allow both geometric and elastomeric movement.
- Factory intersections: Factory-fabricated intersections use special fabrication techniques to ensure watertight, clean seam lines.
- Weather-proof closure: Acts as a flexible, weather-proof exterior cover for expansion joint openings in standard and special applications.
- Patented attachment: The rubber bellows and two metal flanges are adhesively and mechanically combined by a patented bifurcation process.
- Style variety: Designed in a variety of styles to meet different application requirements.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Sell unit | 1 roll |
| Product line | Expand-O-Flash EJ |
| Available colors | ['Mill'] |
| Available sizes | ['4 in.', '6 in.', '8 in.'] |
| Material | Flexible rubber membrane bellows with closed-cell foam support and metal flanges |
| Application | Cant-to-wall and cant-to-cant expansion joints |
| Intended use | Flexible, weather-proof cover for expansion joint openings in commercial roofing |
Coverage & How Much You Need:
One roll covers the run of expansion joint at the selected 4 in., 6 in., or 8 in. nominal opening width; roll length is not stated in the sources. Size the joint by measuring opening width and joint run, and plan factory-fabricated intersections where joints cross or change direction.
Fit and Compatibility:
Designed for use with Johns Manville low-slope roof systems at cant-to-wall and cant-to-cant expansion joint conditions. Expansion joint openings of the corresponding nominal size are required, and mating flashings and attachment fasteners are specified per the project roof system.
Frequently Asked Questions (FAQ):
Q: What sizes does this cover come in?
A: The line includes 4 in., 6 in., and 8 in. cant-to-wall/cant covers, all in mill finish.
Q: How is the cover built?
A: Each cover combines a flexible rubber membrane supported by closed-cell foam to form bellows, with two metal flanges attached by a patented bifurcation process.
Q: What happens where joints intersect or turn corners?
A: The greatest stress occurs at intersections, crosses, and direction changes, so factory-fabricated intersections are produced with special techniques for watertight, clean seam lines.
Q: Does it handle movement in several directions?
A: Yes, it accommodates multidirectional movement through non-reinforced bellows designed for both geometric and elastomeric movement.
Q: What is the sell unit?
A: Each size is sold as a roll; the roll length is not stated in the available product information.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Choose the cover width to match the nominal expansion joint opening: 4 in., 6 in., or 8 in. Order factory-fabricated intersections for any location where joints cross, intersect, or change direction, since that is where movement stress concentrates. The non-reinforced bellows are what allow the cover to follow both geometry changes and elastomeric movement, so avoid field-modifying the bellows during installation.
Install per the roof system manufacturer's specifications and fall-protection requirements when working at the roof edge or near open expansion joints.
Order the Johns Manville Expand-O-Flash EJ expansion joint cover in 4 in., 6 in., or 8 in. widths for a flexible, weather-proof joint closure.
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