Many construction professionals assume that fire ratings are not a concern or lack knowledge of them, when in fact, these ratings affect every trade on a construction site. Fire ratings are one of the most important aspects of safety in buildings, and are an essential component of the construction process. The aim of a fire rating is to protect lives by ensuring there is enough time to safely exit a building, reduce property damage, and ensure compliance with building codes and regulations. This article takes a deep dive into everything you need to know about fire ratings, from what they are, to how they are determined, and what their implications may be for your project.

What are fire ratings?

Fire ratings are assigned to building materials based on their ability to withstand fire exposure for a specified period. These ratings are determined through standardised tests and are crucial for assessing the fire resistance of various building components, such as walls, floors, doors, and structural elements.

The fire ratings of various materials used in a passive fire protection system add to the overall Fire Resistance Level (FRL), which is the estimated ability of a construction element to withstand fire for a specific duration.

How fire ratings are determined

Fire ratings are established through rigorous testing in controlled environments in accordance with Australian Standard AS 1530.4 ‘Methods for fire tests on building materials, components and structures – Fire-resistance test of elements of construction’. Fire tests take the following factors into account –

  • Structural Adequacy – This refers to the capacity of a load-bearing construction element to support a load when exposed to fire. A failure in structural adequacy is identified when the element collapses, or its rate of deflection exceeds the specified limits.
  • Integrity – This is the ability of a construction element to prevent the passage of flames and hot gases from one area to another. Integrity failure is considered to have occurred when there is continuous flaming on the non-exposed side of the test specimen or when cracks, fissures, and other openings that allow hot flames and gases to pass through are present.
  • Insulation – This measures the capacity of a construction element to keep the surface temperature on the side not exposed to the furnace below the specified limits during testing. An insulation failure is deemed to occur when the temperature rise on the non-exposed side exceeds the predetermined thresholds.

Below is an overview of the fire rating test process –

Fire exposure

A sample of the material or assembly is exposed to fire in a controlled furnace that simulates real fire conditions. The furnace’s temperature is increased according to a standard time-temperature curve.

Performance monitoring

During the test, various performance criteria are monitored, including temperature rise, structural integrity, and the ability to prevent flame and smoke penetration.

Rating assignment

Based on the test results, a fire rating is then assigned. The Fire Resistance Level (FRL) is expressed in three parts (as above) – structural adequacy/integrity/insulation. For example, a wall required to meet an FRL of 120/60/30 means that it must maintain structural adequacy for 120 minutes, integrity for 60 minutes, and insulation for 30 minutes, as tested to AS 1530.4.

Implications for your project

Understanding fire ratings and their implications can significantly impact the design, construction, and safety of your project, not only during the construction phase but also in the future.

For starters, understanding fire ratings allows for more informed design decisions. Architects and engineers are able to select materials and assemblies that meet fire safety requirements without compromising aesthetics or functionality. This flexibility is the key to creating innovative and visually appealing spaces, that are as safe as they are visually striking. Below are a few more key areas where fire rating knowledge is a significant benefit –

Compliance with building codes

Building codes and regulations often mandate specific fire ratings for different components of a building (Specification 5 Fire-resisting construction). Compliance with these codes is essential for obtaining building permits and ensuring the safety of occupants. Failing to meet fire rating requirements can result in legal penalties, delays in project completion, and increased liability.

Fire ratings play a role in future-proofing your building against evolving safety standards and regulations. By choosing materials with higher fire ratings, you can ensure that your building remains compliant with potential future updates to fire safety codes.

Improved safety

Choosing materials and assemblies with appropriate fire ratings enhances the safety of your building. Fire-resistant materials can slow the spread of fire, provide more time for evacuation, and reduce the risk of structural collapse. This is particularly important for high-occupancy buildings, such as schools, hospitals, and commercial properties.

Fire ratings protect lives and safeguard property. Materials with higher fire ratings can limit fire damage, reducing repair and replacement costs. This is especially important for valuable assets, historical buildings, and critical infrastructure.

Marketability and reputation

Buildings with robust fire safety measures are considerably more attractive to tenants, buyers, and investors. In fact, a building’s fire ratings can enhance its marketability and reputation, as well as the reputation of the construction company itself.

Tenants are particularly concerned about fire safety in commercial and residential properties. Demonstrating that a building meets or exceeds fire safety standards goes a long way toward instilling confidence. A building equipped with fire-resistant materials and assemblies gives owners, occupants, and stakeholders considerable peace of mind.

In addition, insurance companies often offer lower premiums for buildings constructed with fire-resistant materials and assemblies. Investing in higher fire ratings can lead to long-term cost savings on insurance policies, making your project more financially viable.

Partnering to prioritise fire ratings

Understanding fire ratings and their implications has many benefits, both for the present and the future. By prioritising fire safety through the selection of materials and assemblies with appropriate fire ratings, you can ensure compliance with building codes, enhance a building’s safety, and ultimately improve its marketability.

Fire ratings and their application on construction is a specialised skill, and seeking the assistance of an expert fire protection team is always recommended. This way, you can ensure that your project is effectively safe and fully compliant while learning a wealth of knowledge from experts with years of experience. PROFINISH prides itself not only on our expertise but on the fact that we partner with contractors, architects, designers and trades to ensure they know as much as they can. This ensures that more and more buildings are constructed more safely every day. Contact us for your next project, and we’ll take on your fire ratings together.