​Uncover 5 Roof Hatch and Fire-Rating Explanations You Don't Want to Miss!

Fire ratings and roof hatches are two areas that often confuse architects, contractors, and code officials alike. Do roof hatches need to be fire-rated? If so, in which situations? And how do the codes define these requirements?

The answers aren't always straightforward, but understanding them is essential for compliance and product selection. To clarify things, here are five key explanations that will help you confidently navigate fire ratings and roof hatches.

1. Why Roof Hatches Typically Don't Require Fire Ratings

In most buildings, roof hatches serve as direct access points to the outdoors, which means they don't connect one fire-rated compartment to another. This is why most roof hatches installed in commercial and industrial projects don't carry a fire rating.

According to the International Building Code (IBC), Section 712.1.15 addresses openings in fire-rated roof assemblies. It states that as long as the roof hatch installation doesn't weaken the roof's overall fire-resistance rating, non-fire-rated hatches are permitted.

This explains why a standard steel roof hatch is typically acceptable for most projects. It allows access without interfering with the fire-resistance design of the roof assembly.

2. When a Fire-Rated Roof Hatch Becomes Necessary

Although most projects don't require them, there are scenarios where a fire-rated roof hatch is the correct—and sometimes the only—choice. These include the following:

• Buildings Within 15 Feet of Another Building: When structures are close together, the IBC Section 705.8.6 explains that skylights or roof hatches must be rated to maintain the required fire separation between buildings.
• Stepped Roof Designs: The same fire separation rule applies if part of the roof is higher or lower than an adjacent section. Non-rated hatches could compromise the required protection, so a fire-rated hatch is needed.
• Access From a Fire-Rated Stair Enclosure: Stairwells that extend to the roof must maintain their full fire-resistance rating, which includes the roof hatch at the top.
• Code Official or Project-Specific Requirements: Local inspectors or specifications may call for fire-rated roof hatches in particular applications, even if the base code does not explicitly require them.

Together, these scenarios show that while fire-rated roof hatches are not common, they are important when vertical exposure or continuity of a fire-rated assembly is at stake.

Still not sure if your project falls into one of these categories? Call (888) 327-5471 to speak with our roof hatch experts, or visit our contact page for other ways to get the guidance you need.

3. How Fire-Rated Roof Hatches Are Tested

Unlike standard hatches, fire-rated roof hatches are subject to strict testing to ensure they perform as required. In the U.S., these products are typically UL-listed and rated for specific durations, such as 90 minutes or 3 hours.

During testing, the hatch is installed in a fire-rated assembly and exposed to high heat and flame for the designated time. Afterward, it undergoes additional tests, such as a hose stream test, to evaluate how well the assembly holds up under pressure.

This testing confirms that the fire-rated roof hatch will maintain the roof or wall assembly rating it penetrates when installed correctly. For architects and contractors, this provides confidence that the hatch aligns with the project's compliance needs.

4. Where Building Codes Define Roof Hatch Requirements

Much of the confusion around roof hatch fire ratings comes from mixing references to different building codes. The International Building Code (IBC) and NFPA standards are the primary authorities for U.S. projects. These codes set the framework for fire-resistance-rated assemblies and outline when specialized products, like fire-rated roof hatches, are required.

While other international standards exist—such as European testing under BS EN 1634-1—they are not directly applicable to North American construction. Relying on IBC provisions ensures that design teams stay aligned with the codes enforced by local officials, reducing delays during plan review or inspections.

5. What To Consider When Choosing the Right Roof Hatch

With the code background clarified, the next step is choosing the right hatch. Here's a practical way to think about it:

• Standard Roof Hatch: This is the right choice for most buildings where the hatch leads directly outdoors and requires no fire-resistance rating. It is durable, cost-effective, and widely available in different sizes and configurations.
• Fire-Rated Roof Hatch: Models like the BA-FRHTB Fire-Rated Roof Hatch Thermally Broken are essential when the hatch penetrates a fire-resistance-rated assembly, such as a stair enclosure or shaft. These hatches are designed and tested to maintain the assembly's rating, supporting compliance with IBC and UL requirements.
• Smoke Vent: In certain commercial and industrial projects, a smoke vent may be the best choice to let smoke and heat escape during a fire. For instance, the BA-SVG-SL Smoke Vent Galvanized offers a simple, durable, and code-conscious solution when venting is part of the design.

Architects and contractors can determine the right solution by evaluating the project's design and consulting with code officials when needed.

Get the exact solution your project needs. We can provide a custom roof hatch that considers your project's fire rating requirements, dimensions, and performance specifications. Request your personalized quote today.

Final Thoughts

Roof hatches are essential to modern buildings, enhancing accessibility and maintenance safety. However, their role in fire-rated assemblies can raise big questions.

Fire-rated roof hatches aren't required everywhere, but they become an indispensable part of code compliance when they are. Knowing the difference ensures your project moves smoothly from design to approval to construction.

At Best Access Doors, we make finding exactly what you need easy. Check out our roof hatch catalog to explore all available models, or call us directly at (888) 327-5471 to connect with our specialists for tailored recommendations.