3-Hour Fire-Rated Wall: What It Is and Why It Matters?

What Is a 3-Hour Fire-Rated Wall?

Fire can move very quickly through a building, and as a result, it’s important to choose building materials that can reduce the damage caused by fire. 

The National Building Code of Canada (NBC) and the National Fire Code of Canada (NFC) lay out building requirements that will mitigate the effects of a fire, ideally slowing its spread to allow those inside to evacuate and reduce the damage from the fire. A variety of test methods are used to determine the fire rating based on the thickness of the wall.

Choosing a fire-rated solution for a building envelope can protect the building and the people inside, allowing time to evacuate and mitigate damage in the event of a fire.

What Is a fire-rated Wall?

A fire-rated wall is tested to standards laid out by various agencies to determine how long the assembly will resist the passage of flame and smoke. Once it’s determined how well the wall assembly protects against the spread of fire, it’s given a rating in hours, typically between one and four hours. 

One such test, the Steiner Tunnel test, measures the surface flame spread and smoke developed for the product being tested. If the material is ceiling mounted, the ASTM E84, UL 723, CAN/ULC-S102 tests are performed. For materials installed on the floor, the test will be the CAN/ULC-S102.2 method. This test shows how quickly the flames would spread.

How Are Fire Walls Tested?

Norbec’s NOROC Architectural fire-rated panel .

Fire walls are tested according to various test methods and requirements laid out by the National Fire Protection Agency in the U.S. and other agencies responsible for writing the building codes in Canada and America. 

Norbec’s fire-rated walls are tested using a variety of tests to determine how the insulated metal panels will burn when in contact with fire. The fire rating ultimately depends on the type of core and the thickness of the panel.

NOROC®-L

NOROC^®-L architectural panels  feature a mineral fiber core in various thicknesses that offers superior fire resistance. Its surface burning characteristics according to the ASTM E84 (CAN/ULC-S102 for Canada) methods resulted in FSI of 0 and SDI of 0 for the mineral wool core.  

These panels have the following fire resistance by thickness:

• 5” = 60 minutes
• 6” = 120 minutes
• 8” = 180 minutes

NOROC^®-L panels also have the following properties:

Firewall vs. Fire Separation

A firewall extends from the foundation of a building to its roof. It offers the most fire protection of the three types and is typically constructed from fire-rated materials such as concrete, bricks, or another fire-rated material. Firewall ratings range from one to four hours. 

Fire separations are interior partitions designed to divide different occupancy areas within a building. Unlike firewalls, they extend only from floor to ceiling and are constructed using materials like wood framing, fire-resistant insulation, and gypsum wallboard. These partitions rely on a structural framework for support and must be built with fire-rated materials to meet safety standards. Fire separation walls typically have a fire rating of at least one hour, helping to slow the spread of fire within a building.

NOROC^®-L Fire-Rated Insulated Metal Panels Protect Your Building from Fire     

Fire-rated walls play a huge role in enhancing building safety, particularly in environments where fire resistance is a priority. 

Certain buildings—such as hospitals, schools, government facilities, and multi-unit residences—require higher fire protection standards to safeguard occupants and comply with strict building codes. 

The NOROC®-L panel, with its mineral fiber core, not only provides superior fire resistance but also delivers excellent insulation for enhanced energy efficiency and can contribute to LEED certification.

Contact the experts at NORBEC today to discuss how our insulated metal panels can prevent the spread of fire and protect your building.