2-hour fire-rated windows feature multi-layered glass with intumescent interlayers…
How Were 2 Hour Fire Rated Windows Invented?
Fire rated windows have undergone significant transformations over the centuries. In the late 19th century, the industrial boom led to the development of wired glass, which incorporated a mesh of thin metal wire embedded within the glass. This design aimed to prevent the glass from shattering under thermal stress, thereby enhancing its fire-resistant properties. Wired glass became a staple in factories and densely populated buildings, marking one of the earliest attempts to integrate fire resistance into window design. By the end of the 19th century, fire protection had become a major consideration in the design of industrial structures. One important type of fireproof window design, developed by the 1890s, was the hollow-core sheet-metal window.
The late 20th and early 21st centuries witnessed remarkable advancements in fire rated glass technology. Innovations such as multi-layered laminated glass, intumescent interlayers, and specialized coatings have significantly enhanced the fire resistance of windows.
2 Hour Fire Rated Windows – Timber Frames
2-hour timber-framed fire-resistant windows offer a natural and traditional appearance. These windows can be made from various types of wood, such as spruce, pine, larch, or oak and many more. They can be tinted to match other windows in the building, allowing for design consistency.
Modern timber fire-resistant windows use special glass that contains a transparent gel. This gel expands and forms a protective layer when exposed to high temperatures, helping to block heat and flames. These windows can offer fire resistance for more than 30 minutes and, in some fixed parts, up to 60 minutes.
Timber frames can also be customized in different shapes and designs, such as curved, angled, or motorized windows. This makes timber a flexible option for projects that require unique designs.
Some common classifications for timber fire-resistant windows include:
- EI30 Rating: Provides 30 minutes of fire resistance for windows and entrance doors.
- EI60 Rating: Offers 60 minutes of fire resistance for larger, fixed windows.
Timber windows can be made in a variety of sizes to meet different design needs. Installation is straightforward, using standard hardware. Fire tape is not required, but it’s important to follow assembly instructions because these windows can be heavy. Most fire-resistant timber windows come with a key handle and are designed to be opened only for cleaning. In areas where cleaning access is easy, fixed glazing is often recommended as a more affordable option.
2 Hour Fire Rated Windows – Steel Frames
Steel-framed windows and doors are known for their strength and high fire resistance. These frames can be made using hot-rolled or cold-formed steel profiles and are designed to protect against fire for 30, 60, or even up to 120 minutes, depending on the system used.
Steel windows can also be customized for internal or external use. For example, internal windows can provide 30 minutes of fire resistance, while external fixed windows can achieve up to 60 minutes. Some advanced systems can offer fire protection for up to 120 minutes.
Steel frames allow for slim designs, which let in more natural light while still providing fire protection. Although steel conducts heat, special glazing and thermal barriers can help reduce heat transfer during a fire.
Choosing the Best Option
The decision between timber and steel frames for 2-hour fire-rated windows depends on several factors:
- Design: Timber provides a natural, traditional look, while steel offers a modern, minimalist appearance.
- Fire Safety: Both materials can meet fire safety standards, but steel can offer longer fire resistance with less maintenance.
- Maintenance: Timber requires regular care to maintain its fire-resistant properties, while steel is more durable over time.
- Environmental Impact: Timber is renewable when sourced responsibly, and steel is recyclable, which supports sustainability.
- Customization: Timber allows for a wider variety of shapes and finishes, while steel is better suited for slim, large-window designs.
How Do 2-Hour Fire-Rated Windows Work?
2-hour fire-rated windows are designed to resist fire and heat for at least two hours, helping to prevent the spread of flames and smoke. These windows play a crucial role in maintaining building safety by providing extra time for evacuation and limiting structural damage. Understanding how they work involves looking at their materials, design, and the principles behind fire resistance.
Key Materials of 2-Hour Fire-Rated Windows
- Fire-Resistant Glass
The core element of any fire-rated window is its specialized glass, which is designed to withstand high temperatures and thermal shock. Common types include:
- Wired Glass: An early form of fire-resistant glass that incorporates a mesh of metal wires. The wires hold the glass in place if it breaks under heat, though this method is less common today due to advancements in technology.
- Laminated Fire-Resistant Glass: This consists of multiple layers of glass bonded with interlayers, such as intumescent material. When exposed to heat, the interlayer expands to form an insulating barrier that blocks heat and flames.
- Gel-Filled Glass: Some modern fire-resistant windows use glass that contains a clear, heat-sensitive gel. Under high temperatures, the gel foams and acts as a heat shield, preventing fire and heat from passing through the window.
- Intumescent Interlayers
Intumescent materials are key in many fire-resistant glass systems. These materials remain stable at normal temperatures but expand significantly when exposed to heat, forming a thick, insulating barrier. This barrier helps prevent the transfer of heat and can slow the spread of fire. - Fire-Rated Frames
As mentioned previously, the frame must be as fire-resistant as the glass to maintain the integrity of the entire window.
Seals and Gaskets
Fire-rated windows also include special seals that expand when exposed to heat. These seals block gaps that could allow smoke or flames to pass through. Some systems also feature automatic closing mechanisms to ensure the window remains securely shut during a fire.
2 Hour Fire Rated Windows – Testing and Safety Standards
To ensure reliability, 2-hour fire-rated windows undergo rigorous testing according to industry standards. Tests simulate real fire conditions to assess how well the windows resist heat, flames, and structural stress over time. Common standards include:
- British Standard BS 476: Evaluates fire resistance by exposing the window to controlled heat and flame over a set period.
- ASTM E119: A standard in the United States that tests how long materials can withstand fire exposure while maintaining structural integrity.
- European Standard EN 13501: Classifies fire resistance based on integrity (E) and insulation (I) criteria.
A 2-hour fire rating means the window has passed these tests by maintaining its structural integrity and limiting heat transfer for at least 120 minutes.
Why Are 2-Hour Fire-Rated Windows Important?
- Containment: They help prevent the spread of fire from one area to another, especially in high-risk buildings like hospitals, commercial centers, or high-rise apartments.
- Safety: By resisting fire for two hours, they provide critical time for evacuation and for firefighters to control the blaze.
- Compliance: Many building codes require fire-rated windows in specific areas, such as stairwells, corridors, or close to property lines.
Stay Safe With Fireresist.co
The excellent performance of our 2 hour fire rated windows stems from a combination of glazing technologies, framing systems, sealing mechanisms, compliance with rigorous testing standards, and most importantly, talent and passion for creating high quality products. Investing in your safety always pays out!