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Karnak 31 Fiberglass Membrane Fabric, 4 in. to 36 in. x 150 ft Rolls
Regular price $14.00Orders start at $399 — combine any items to reach the minimum. Learn more
Karnak 31 Fiberglass Membrane Fabric, 4 in. to 36 in. x 150 ft Rolls
Karnak 31 Fiberglass Membrane is a waterproofing fabric woven entirely of fiberglass yarn, sold in black rolls from 4 in. to 36 in. wide by 150 ft long. It is designed for use with cold application cements and coatings and conforms to contours and bends without cracking. High flexibility and tensile strength make it well suited to general roofing and waterproofing maintenance.
Key Features:
- Pure Fiberglass Weave: Woven entirely of fiberglass yarn for a durable waterproofing fabric.
- Contour Flexibility: High flexibility conforms to all contours and bends without cracking.
- High Tensile Strength: Provides high tensile strength for reinforcement in cold-applied systems.
- Mildew & Rot Resistant: Will not mildew, rot or decay over time.
- Chemical Resistant: Acid and alkali-resistant for demanding maintenance environments.
- Multiple Widths: Available in 4 in., 6 in., 12 in. and 36 in. widths, all 150 ft long.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Karnak |
| Sell unit | 1 roll, selected width x 150 ft |
| Product line | Karnak 31 Fiberglass Membrane |
| Available colors | ['Black'] |
| Available sizes | ['4 in. x 150 ft', '6 in. x 150 ft', '12 in. x 150 ft', '36 in. x 150 ft'] |
| Material | Fiberglass yarn (woven fabric) |
| Color / finish | Black |
| Dimensions | Available in 4 in., 6 in., 12 in. and 36 in. widths by 150 ft length |
| Coverage per unit | 150 linear feet per roll at the selected width |
| Intended use | Reinforcement fabric for cold application cements and coatings in roofing and waterproofing maintenance |
Coverage & How Much You Need:
Each roll provides 150 linear feet of reinforcement at the chosen width. Select 4 in. or 6 in. for seams and detail work, 12 in. for wider joints, and 36 in. for larger reinforced areas; embed the fabric fully into the coating with slight overlap at seams.
Fit and Compatibility:
Designed for use with cold application cements and coatings in general roofing and waterproofing maintenance. Pair with the compatible Karnak cement or coating specified for your system; primers and coatings are sold separately.
Frequently Asked Questions (FAQ):
Q: What widths and lengths are available?
A: Rolls come in 4 in., 6 in., 12 in. and 36 in. widths, each 150 ft long.
Q: What is included in the sell unit?
A: One roll of Karnak 31 fiberglass membrane in the selected width and 150 ft length.
Q: How do I choose a width?
A: Narrower widths suit seams, flashings and detail work, while the 36 in. width reinforces larger field areas or repairs.
Q: What cements and coatings does it work with?
A: It is designed for use with cold application cements and coatings; confirm compatibility with the specific product in your system.
Q: How is it installed?
A: Embed the fabric into the wet cement or coating, conforming it to contours and bends, then coat over to fully encapsulate the fabric.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Choose this fiberglass membrane to reinforce cold-applied coatings and cements across flashing details, seams and full field repairs where flexibility over movement is needed. Work the fabric into wet coating to eliminate wrinkles and air pockets, then apply a full top coat so no fabric remains exposed. For narrow seam work use the 4 in. or 6 in. roll; move up to 12 in. or 36 in. when reinforcing larger areas.
Fiberglass fibers can irritate skin; wear gloves and long sleeves when handling, and follow the coating manufacturer's safety instructions during installation.
Order Karnak 31 Fiberglass Membrane in the width you need and reinforce your cold-applied roofing system.
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