Exterior trim is one of the most vulnerable components of a building’s envelope, constantly exposed to moisture, temperature fluctuations, and biological decay. Armorite by Roseburg Forest Products is a specialized exterior Medium Density Fiberboard (MDF) engineered specifically to overcome the traditional limitations of wood and standard composite trim.
By utilizing advanced material science and moisture-resistant resins, Armorite provides a high-performance solution for non-structural exterior applications.
The Engineering of Armorite: MR50 Rating
The primary technical advantage of Armorite is its MR50 rating, which indicates the product has passed rigorous testing for moisture resistance, including thickness swell and bond integrity after submersion..
- Moisture-Resistant Resins: Unlike standard MDF, Armorite is manufactured using a formaldehyde-free (NAF) resin system specifically designed for wet environments.
- Decay and Termite Protection: The substrate is treated with zinc borate throughout the thickness of the board. Ensuring that the material is protected against fungal decay and termite infestations, even if the board is cut or routed in the field.
Machinability and Architectural Detail
For many exterior projects, the choice of material is dictated by how well it can be customized. Armorite offers the workability of natural wood with the consistency of an engineered composite.
- No Grain or Knots: Because Armorite is a composite material, it lacks the knots, voids, or grain patterns that can lead to splitting or uneven weathering in natural cedar or pine.
- Superior Routing: The dense, uniform core allows for intricate CNC machining and routing. This makes it an ideal substrate for custom architectural millwork, brackets, and decorative cornices where sharp, clean lines are required.
- Field Workability: The material can be cut, fastened, and installed using standard woodworking tools, providing efficiency for complex installations.
Finishing and Surface Performance
Armorite is designed to provide a “best-in-class” finish for painted exterior applications. The surface is exceptionally smooth, which reduces the amount of prep work required compared to traditional timber.
- Paint Adhesion: The smooth, consistent surface provides a superior bond for exterior paint systems. This results in a finish that resists peeling and maintains its aesthetic appeal longer than wood, which often experiences “grain telegraphing” over time.
- Factory Priming: Armorite is typically provided with a high-quality factory primer on all six sides, ensuring that the core is protected from the moment it arrives at the project site.
Versatile Exterior Applications
Armorite is engineered for a wide range of non-structural exterior uses where durability and detail are paramount:
- Exterior Trim and Fascia: Providing a smooth, rot-resistant border for rooflines and corners.
- Window and Door Surrounds: Ensuring a stable, paintable surface that won’t warp or twist near openings.
- Decorative Millwork: Creating custom pilasters, columns, and soffit systems that require high-definition detailing.
- Outdoor Signage: Offering a stable substrate for commercial or residential signage exposed to the elements.
Technical Specifications and Compliance
Armorite is manufactured to meet stringent industry standards for safety and environmental impact. It is a No-Added Formaldehyde (NAF) product, contributing to healthier environments and meeting various green building certifications. Its consistent density and thickness tolerances ensure predictable performance across large-scale architectural projects.
