Optimum has revolutionized the construction industry by offering the most comprehensive line of fire-rated steel windows and doors. With fire-ratings ranging from 45 to 90 minutes, Optimum’s Fire-Rated Windows are put through rigorous testing.

Initially, a “heat test” is performed, where-in the window is exposed to temperatures up to 1600 degrees Fahrenheit. Fire-Rated Windows also endure the “Hose Stream Test”, in which the glass holds fast even during this extreme change in temperature. When other windows made from materials such as aluminum, vinyl and wood are placed under these extreme conditions, they will poorly react in a Thermal Shock. Optimum Fire-Rated windows will hold their integrity.

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  • From 20 to 90 Minute Fire-Rating
  • Produced in Cold-Rolled and Hot-Rolled Steel
  • As Low as .42 U Value
  • Energy-Efficient (NFRC RATED)
  • Self-Closing Mechanism on Operable Units
  • Factory Glazed Finish
  • Standard Powder Coat Paint Finish
  • Factory Glazed (Wire & Ceramic Insulated Glass)
  • Factory powder coated Finish
  • Standard Colors and Custom Colors available



(Click below more information)


The period of time a building element, component or assembly maintains the ability to confine a fire. Fire-Ratings are stated in minutes or hours. Its designation indicates the duration of the fire test exposure to which a fire door or fire window assembly was exposed and which it successfully met all acceptance criteria.


HOSE STREAM TESTED Following the conclusion of the fire test, the hose stream test is conducted to see if the glass can remain intact when exposed to the impact and thermal shock of a fire hose. The heat of the fire causes the glass to expand, while cold, water causes the glass to contract; stress created by these different reactions is thermal shock.

UL Classified & Labeled

UL CLASSIFIED & LABELED“UL" is short for Underwriters Laboratories, an organization which has been testing and approving products for consumer safety since 1894. Optimum's Fire-Rated Products are all Listed and Classified by Underwriters Laborato ries, Inc.®

positive pressure
positive pressureDuring fire conditions, head develops within the source area, pressure within an enclosed room begins to build relative to the pressure outside the room. As heat rises, pressure continues to build, creating strain on the door or window assembly. Optimum's Fire-Rated Products have been tested in compliance to UL10C standard.



Product Description

Optimum’s 45-90 Minute Fire-Rated Double-Hung Windows are used in non-temperature rise applications and through various glazing options can be modified to address most fire-rated applications. Its narrow profiles providing open vision areas allows natural daylight without compromising life safety and design flexibility. The entire Fire-Rated line has been through rigorous testing. Initially, a “heat test” is performed where the window/door is exposed to temperatures up to 1600 degrees Fahrenheit. They will then endure the “Hose Stream Test”, wherein which the glass holds fast even during this extreme change in temperature. Where other units of different material will react poorly when placed under these extreme conditions, Optimum’s Fire-Rated Steel Window & Doors will hold and maintain its integrity.

Min. Frame Dimension20″ x 30″20″ x 30″20″ x 30″
Max. Frame Dimensions60″ x 120″60” x 120”56 1⁄2” x 120”
Wire Glass Max. Exposed Area1,296 in2N/AN/A
Ceramic Glass Max. Exposed Area3,325 in23,325 in22,627 in2


  • Cold-Rolled sections formed from GALVANIZED STEEL
  • EPDM and Silicone Pile Weather-Stripping
  • 4 1⁄4” Exterior frame depth , 4 1/16” Ext Jamb depth
  • Installation straps available upon request
  • Half Screens & Limited Operation Stops are available
  • Zinc Enriched Primer and Powder Coat Finish
  • One Lift Handle per lower sash up to 23”, two handles thereafter
  • Can Accommodate glazing ranging from 3/16” to 3/4” in O.A thickness
  • One Sweep Lock at center of sash up to 30′′, two sweep locks thereafter
  • Factory Glazed; Glass held in place via mechanically fastened steel glazing beads
US Testing/CompliantUL10C, UL9, NFPA 80, NFPA 257, ASTM E283, ASTM E331 & ASTM E330
CAN Testing/CompliantCAN/ULC-12349
Custom ColorsAvailable
FabricationCoped and Mechanically assembled
CertificationUnderwriters Laboratories
Fabricated in the USYes
Glazing Options45 Min Rating w/ Wire Glass; 45-90 Min Rating w/ Ceramic Glass
Weight (lbs/linear ft.)1 1⁄4 lbs/lf for Vent Frame; 2.85 lbs/lf for Exterior Frame
Approval For NYCMEA# 151-91-M
FR7650 Fire Rated windows
FR7650TSH Fire Rated Window
Fire Rated Windows historic application
FR4700 Fire Rated Windows
FR8600 Fire Rated Window
FR7650 Fire Rated windows
FR7650TSH Fire Rated Window
Fire Rated Windows historic application
FR4700 Fire Rated Windows
FR8600 Fire Rated Window

Optimum’s Fire-Rated products are classified and labeled by Underwriters Laboratories, Inc. ® and Underwriters Laboratories of  Canada. File number for labeled fire-rated assemblies is UL File No. R12349. Tests performed in accordance with:

UL 9 NFPA 80 ASTM E283
UL 10C
NFPA 257