12 oz. Woven Glass Fabric – 30" x 30" Sheet
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Heavy-Weight Woven Fiberglass Cloth for Structural Reinforcement
This 12 oz. woven glass fabric is a heavy-duty reinforcement cloth designed for applications that demand maximum strength and impact resistance. Cut to a convenient 30" × 30" sheet, it's well-suited for localized structural repairs, high-load laminate patches, and reinforcing areas subject to abrasion or impact — such as keels, skegs, transoms, and hull bottom sections.
At twice the weight of standard 6 oz. cloth, the 12 oz. weave builds thickness and stiffness quickly, reducing the number of layers needed to achieve structural laminate targets. It wets out with epoxy, polyester, or vinylester resin systems and can be painted or varnished once fully cured.
Key Features
- 12 oz. heavy-weight woven fiberglass — maximum strength per layer
- 30" × 30" pre-cut sheet — ideal for patch repairs and localized reinforcement
- Builds thickness and stiffness faster than lighter fabrics
- Compatible with epoxy, polyester, and vinylester resin systems
- Suitable for use over wood or existing fiberglass substrates
- Paintable and varnishable once cured
Common Applications
- Structural hull repairs — keel, skeg, transom, and bottom sections
- High-load laminate patches on decks and bulkheads
- Abrasion-resistant overlays on wear surfaces
- Reinforcing through-hull areas and fitting pads
Related Fiberglass Fabrics
For lighter sheathing and laminating work, see the 4 oz. Woven Glass Fabric – 50" Wide, 10 Yard Roll or the 6 oz. Woven Glass Fabric – 60" Wide, 20 Yard Roll. Pair with the West System C205 Fast Hardener for standard conditions or the West System 206 Slow Hardener for extended working time on larger patches.
Parts Desk Insights
Best Use Case: The 12 oz. sheet is the right choice for customers doing structural patch repairs where strength is the priority over cosmetics — think keel repairs, transom rebuilds, or reinforcing high-stress areas. The 30" × 30" format is a practical size for most single-location repairs without the waste of buying a full roll. Steer customers toward lighter fabrics (4 oz. or 6 oz.) if they’re sheathing wood or doing cosmetic repairs where a smooth, transparent finish matters — the 12 oz. weave is harder to wet out smoothly and won’t go transparent. Recommend a slow hardener for large patches to allow adequate wet-out time before the resin begins to gel.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.