Common Fire Stopping Mistakes and How to Avoid Them

Fire stopping is an essential part of any building’s passive fire protection strategy. When installed correctly, it helps contain fire and smoke within designated compartments, giving occupants time to evacuate safely and protecting the structure. But fire stopping can often be installed incorrectly or is neglected over time.

Below, we highlight some of the most common mistakes we encounter- and how to avoid them.

Common Fire Stopping Mistakes

Using the Wrong Materials

One of the most frequent issues is the use of inappropriate products. For example, some contractors still attempt to fill penetrations with foam, cement, or other materials that aren’t tested for fire stopping.

How to avoid it: Always use third-party tested, certified fire stopping systems that are approved for the specific application. Check the product documentation and make sure it’s suitable for the substrate, penetration type, and fire rating required.

Incomplete Seals Around Services

Another common mistake is leaving gaps around cables, pipes, or ducts. Even small gaps can allow smoke and fire to spread rapidly. 

How to avoid it: Inspect every penetration carefully. All voids must be fully sealed according to the manufacturer’s instructions, and fire stopping should be installed to the full depth of the opening.

Mixing Incompatible Products

Some installers combine products from different manufacturers in a single penetration, assuming they’ll work together. In reality, mixing products can void their fire ratings and create compliance issues.

How to avoid it: Stick to tested systems as a complete solution. If you need to use different products, check that they’ve been tested together and meet the necessary approvals.

Poor Workmanship

Even high-quality products won’t perform if they’re installed incorrectly—like rushed applications, uneven fills, or missing components (such as backing materials or collars).

How to avoid it: Ensure all installers are properly trained and competent. Supervise installations and carry out quality checks to confirm workmanship meets the required standard.

Lack of Labelling and Documentation

Building owners and future contractors need to know what’s been installed and where. Without proper labelling and records, fire stopping can be damaged or removed during later works without anyone realising.

How to avoid it: Label all firestopped penetrations clearly and keep accurate records, including photos, product data sheets, and installation details. This also helps demonstrate compliance to building control and insurers.

No Ongoing Inspection and Maintenance

Fire stopping isn’t “fit and forget.” Over time, new services are installed, or existing penetrations are altered, compromising compartmentation.

How to avoid it: Schedule regular inspections of your fire stopping as part of your building’s fire safety strategy. Any breaches or damage should be remediated promptly by qualified professionals.