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Johns Manville Expand-O-Flash CF Curb-to-Curb Expansion Joint Cover, 4 in. or 6 in. Sizes
Regular price $1,247.50Orders start at $399 — combine any items to reach the minimum. Learn more
Johns Manville Expand-O-Flash CF Curb-to-Curb Expansion Joint Cover, 4 in. or 6 in. Sizes
The Johns Manville Expand-O-Flash CF is a flexible, weather-proof expansion joint cover for curb-to-curb joint openings on commercial roofs. Each cover combines a flexible rubber membrane supported by closed-cell foam bellows with two metal flanges bonded by a patented bifurcation process. Available in 4 in. and 6 in. sizes; factory-fabricated intersections are available separately for crossings and direction changes.
Key Features:
- Multidirectional movement: Accommodates multidirectional movement at roof expansion joints.
- Non-reinforced bellows: Non-reinforced bellows handle both geometric and elastomeric movement.
- Watertight intersections: Factory-fabricated intersections use special fabrication techniques for watertight, clean seam lines.
- Multiple styles: Designed in a variety of styles to match application requirements.
- Custom fabrication: Can be custom designed for special needs beyond standard intersections.
- Bifurcated flanges: Two metal flanges are adhesively and mechanically combined to the bellows by a patented bifurcation process.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Sell unit | 4 in.: 1 box; 6 in.: 1 piece |
| Product line | Expand-O-Flash |
| Available sizes | 4 in., 6 in. |
| Dimensions | CF cover sized to the joint opening; 4 in. and 6 in. variants listed |
| Material | Flexible rubber membrane over closed-cell foam bellows with metal flanges |
| Component type | Expansion joint cover |
| Intended use | Weather-proof exterior cover for expansion joint openings on commercial roof systems |
| Assembly | Factory-fabricated; intersections factory crafted or custom designed |
| Coverage per unit | 1 cover per joint opening section |
Coverage & How Much You Need:
One cover serves a single run of expansion joint opening; the 4 in. and 6 in. sizes must match the nominal joint width. Factory-fabricated intersections cover points where joints cross or change direction.
Fit and Compatibility:
Part of the Johns Manville Expand-O-Flash expansion joint cover line for standard and special applications on JM roof systems. Factory-fabricated intersections and JM-approved adhesives are ordered separately; confirm joint size before ordering.
Frequently Asked Questions (FAQ):
Q: What is included with one cover?
A: One flexible bellows cover with two attached metal flanges; intersections and adhesives are ordered separately.
Q: Which size should I order?
A: Match the cover size to the nominal expansion joint opening: 4 in. or 6 in.
Q: How are corners and T-intersections handled?
A: JM offers factory-fabricated intersections designed for maximum flexibility and watertight seam lines, or custom designs for special needs.
Q: How does it stay watertight as the joint moves?
A: The rubber membrane forms flexible bellows over closed-cell foam, and flanges are mechanically and adhesively combined by JM's patented bifurcation process.
Q: Can it handle movement in more than one direction?
A: Yes, the manufacturer states it accommodates multidirectional movement, with the greatest stress where joints intersect or change direction.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Order the CF cover to match the nominal joint width, and plan intersections at every point where joints cross or change direction, since that is where stress concentrates. Factory-fabricated intersections save labor and produce cleaner, watertight seams than field-cut joints. Follow the JM system specification for flange termination and adhesives.
Expansion joint work is performed at open roof penetrations and near the roof edge; use fall protection and verify the joint is properly supported before walking on or installing the cover.
Order the Johns Manville Expand-O-Flash CF expansion joint cover in 4 in. or 6 in. for a flexible, watertight joint solution.
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