FREP Hangers: A Rust-Free Alternative with Built-In Moisture Management
September 4, 2025
In the ongoing effort to improve durability and performance in timber framing, FREP (Fibre Reinforced Engineered Polymer) hangers offer a compelling alternative to traditional metal connectors—especially in environments where corrosion is a concern.
Why FREP Hangers Will Never Rust
Where metal hangers require protective coatings (ZMAX, Zinc Plated, Hot Dip Galvanised), FREP hangers eliminate the need for corrosion protection altogether. FREP hangers are non-metallic, meaning they are completely immune to rust and corrosion. This makes them ideal for use in:
- Coastal and marine environments
- Structures with preservative-treated timber
- Areas with high humidity or chemical exposure
Ventilation Ridges: Built-In Moisture Control
FREP hangers feature ventilation ridges on the seat of the hanger—an innovation designed to promote joist breathability. These ridges:
- Allow air circulation beneath the joist
- Reduce moisture buildup at the connection point
- Help prevent timber decay and mould growth
This design is especially beneficial in enclosed subfloor spaces or humid climates, where trapped moisture can compromise both timber and metal connectors over time.
Conclusion
FREP hangers represent a next-generation solution for timber framing. With zero corrosion risk, built-in ventilation, and adequate structural capacity, they offer engineers and builders a reliable, long-lasting alternative to traditional metal connectors—especially in challenging environmental conditions.
Note:
- Image 1 shows a typical galvanised hanger that has rusted away a few years after being installed under a saltwater pool deck.
- Image 3 shows the ventilation ridges.
Structural Connections
Unmatched Quality from the Truss to the Foundation
With nearly 60 years of field and R&D experience, Simpson Strong-Tie® timber connectors are manufactured to the industry's highest standards. From framing angles to straps to heavy-duty joist hangers, we offer the most diverse product line so that you have the right product for the job.
Simpson Strong-Tie® connectors offer unmatched quality with laboratory and field testing, and are backed by our uncompromising commitment to customer service. As the company that built the connector industry, you can count on Simpson Strong-Tie® to work closely with builders, engineers and building officials to deliver innovative, building code-compliant solutions to help build safer, stronger structures economically. Download the Timber Connectors NZS 3604 Catalogue.
Timber Connectors
From testing to service to availability, everything we do is engineered to ensure your project's success. With every product, you know you are getting the quality, value, service and on-time delivery that we have built our reputation on for the past 60 years.
From straps and ties to joist hangers and much more, Simpson Strong-Tie® structural connectors increase the strength and safety of timber-frame structures. Each connector is unique to Simpson Strong-Tie and is designed for specific applications without the need to adapt metal plating to suit a connection. Download the Timber Construction Connectors Catalogue (2016-2018).
Steel Frame Connectors
From fully tested and engineered connectors and clips Simpson Strong-Tie® provides comprehensive structural solutions for cold-formed steel construction. From steel-to-steel connections to full-scale lateral solutions and curtain wall connectors, we remain committed to developing new technology that helps to advance the cold-formed steel industry.
Find out how Simpson Strong-Tie timber connectors can help you build the right way every day. Download the Cold-Fromed Steel Construction Connectors Catalogue.
