A Legacy of Safety and Style
For decades, Optimum Window has stood as the trusted name in Fire-Rated steel window manufacturing, earning the confidence of architects, builders, and homeowners nationwide.
In the photo above, our skilled craftspeople are hard at work creating the FR4700 Steel Casement Window — a system known for its strength, precision, and enduring design. Every frame reflects years of expertise, backed by UL certification and meticulous American craftsmanship.
The FR4700 Series: Designed for Protection
The FR4700 Steel Casement Window is UL-approved and certified for up to a 45-minute fire rating, ensuring critical safety in environments where fire containment is vital — from high-rise structures to residential buildings.
Engineered to withstand heat tests of up to 1600°F and a demanding Hose Stream Test, these windows hold their integrity where other materials fail. That makes the FR4700 the gold standard for fire-rated performance without aesthetic compromise.
| Feature | Specification |
|---|---|
| Fire Rating | Up to 45 Minutes |
| Steel Type | Cold-Rolled, Galvanized Steel |
| Certification | UL Listed / NYC MEA Approved |
| Glazing Range | 3/16” to 1” O.A. thickness |
| Finish | Zinc-Enriched Primer + Powder Coat |
| Standard Hardware | White Bronze Cam Locks |
| Testing Standards | ASTM E283, E331, E330 |
Built for Beauty and Reliability
At Optimum, fire protection doesn’t mean design limitation.
The FR4700 line combines thin, elegant sightlines with the rugged durability of steel. Whether installed in modern commercial towers or historic restorations, these windows balance strength and sophistication.
Each unit is factory glazed, painted, and assembled, ensuring that installation is fast and error-free. The frames feature mechanically fastened steel glazing beads and spring-loaded hinges, guaranteeing both durability and smooth operation.
Customizable for Every Vision
Safety may be the priority, but customization makes it truly stand out.
Our FR4700 Casement Windows offer:
- RAL color options for design flexibility
- Insulated glass for energy performance
- Applied flat grids or clear wireless fire-rated glass
- Screens for in-swing and out-swing styles
Every element is adaptable, allowing designers and builders to meet both code requirements and creative intent.
Engineered for Modern Needs
Energy efficiency and sustainability drive modern construction, and the FR4700 meets those demands too.
Its thermal performance meets NYC Energy Conservation Code standards, offering:
- U-Value as low as 0.55 BTU/hr/ft²/°F
- SHGC (Solar Heat Gain Coefficient) of 0.35
- Condensation resistance of 16
Combined with our powder-coated finish, this system is both high-performing and environmentally responsible, containing 100% recycled steel and zero-VOC coatings.
Craftsmanship That Inspires Confidence
Behind every FR4700 window is a team of experts in Ellenville, NY, dedicated to producing secure, reliable, and beautifully finished products.
From design consultation to final inspection, our process blends handcrafted precision with advanced manufacturing technology. This ensures each unit not only protects but enhances the architectural intent of the space it serves.
Safety-Minded, Design-Driven
When you choose the FR4700 Steel Casement Window, you’re choosing more than compliance — you’re choosing confidence.
Our products give architects freedom, contractors reliability, and occupants peace of mind. Each window is proof that safety and design can coexist beautifully.
Key Takeaways
| Benefit | Why It Matters |
|---|---|
| Fire-Rated Protection | Keeps occupants safe, meets NYC and UL standards |
| Customizable Design | Blends into any architectural style |
| American-Made Quality | Manufactured and tested in New York |
| Sustainable Construction | Made from 100% recycled steel |
| Long-Term Durability | Corrosion-resistant and backed by warranty |
From the first weld to final inspection, Optimum’s FR4700 Steel Casement Window reflects the dedication of our team and the trust of our clients.
Fire-rated strength. Architectural elegance. American craftsmanship.
That’s Optimum Window — the name behind safety, reliability, and timeless design.