The most common mistakes when it comes to fire stopping
Passive fire protection (PFP) systems are an important part of a comprehensive, balanced approach to fire protection. Based on compartmentation and containment of fire, PFP systems aim to prevent/slow the spread of fire from one compartment to another. This can be achieved by the use of fire barriers (fire-rated walls and floors).
These fire barriers can have multiple service penetrations that if not properly sealed, can compromise the FRL of the fire-rated elements and their ability to contain smoke, gases, and flames. Each of these penetrations can spread a fire to the neighbouring compartments. If penetrations or gaps are not properly sealed with approved fire sealants, fire collars or coatings, the fire will spread and destroy other parts of the building. Firestops are used to seal penetrations in fire-resistant walls and floors, including
- Through penetrations which pass all the way through the fire barrier to accommodate electrical wiring, plumbing pipes, or parts of the building’s mechanical systems
- Membrane penetrations which pass through only part of the barrier, such as outlet boxes, sink drains or conduit that leads from an opening to a space in the wall or ceiling.
- Building joints where building elements meet within fire-resistance rated wall or floor assemblies
- Junctions between fire-resistance rated wall or floor assemblies
- Openings made in anticipation of future needs
- Firestops that have been reopened
The reliability of the full fire protection solution will ultimately depend on the quality of the installation of the firestopping systems.
Firestop Mistakes That Compromise Fire Protection
Using the wrong material for a specific application
Firestop materials are developed for specific applications.
It is critical to choose the correct system for the type of penetration you’re working with and the fire rating of the barrier in which it will be installed. Here are some important rules to follow when it comes to the materials used in firestops:
- Do not mix manufacturers’ products in the same penetration (unless otherwise tested together). Mixing different brands of materials in the same penetration will void the fire rating of the approved system.
- Only install products that are tested and approved in line with AS1530.4 and in AS 4072.1
- Ensure the installation matches the tested or assessed system.
Incorrect or poor installation of firestop systems
Improper installation is probably the most common mistake in firestopping. While it may be tempting to take shortcuts, following the instructions specific to the system being installed and with great attention to detail is the only way to ensure the integrity of the fire rating.
Make sure the installation is done by trained and certified professionals and that the training is done by the product manufacturer.
Not installing firestop
Believe it or not, it often happens that building inspectors examine fire-rated walls/ceilings and find no firestop at all. This can occur when it’s not determined which contractor is responsible for firestopping or when there’s a lack of education about firestopping codes, or on some occasions, when there are deliberate code violations. The building cannot be effectively compartmentalised if the service penetrations through walls and floors simply allow flames, heat and smoke to pass through unhindered. Since all buildings that have fire-rated walls or ceilings are subject to strict rules, the specifiers should define firestopping systems in the project documentation.
Using not tested products
Untested products can be unreliable and fail to perform as intended or as claimed by the manufacturer. It is best practice to ensure all firestopping products specified and fitted in a building are properly third-party tested and certified to AS 1530: Part 4 and AS 4072 Part 1. Third-party accreditation provides assurance that the product is fit for purpose, is made using a defined quality system and proves a traceable link between what is made in the factory and what was tested in the lab.
The annular space isn’t right
Annular space is the gap between penetrating material (e.g. cables, cable trays, or pipes) and the inside edge of the penetration opening. This space will vary based on the size and shape of the opening and the penetrating material. For each installation, there is a range of maximum and minimum annular space that the installation needs to adhere to.
If there’s too much or too little annular space after installation, the firestopping system will not be able to perform its intended function. As a result, smoke or fire can leak through any gaps or the firestopping component may not be able to remain in place during a fire.
The space between the side of penetration opening and the penetrating material needs to be filled with a tested fire sealant system, according to specific test approvals. Always carefully follow the instructions of the manufacturer of the system or attend a training session to make sure you make the right choice.
Firestopping is not included early enough in the design process
Fire penetrations from project to project can be vastly different. It is important to spend time early on in the project ensuring a passive fire management plan is in place and make sure the right products and systems are used on the job site. The specifier or planner needs to select the most effective firestopping solution that fits into the whole fire protection plan. Good communication and cooperation between specifiers, suppliers, and contractors are key to getting the job done properly and to eliminating additional work or costs down the road.
Some key principles for ensuring compliance with fire stopping:
- Only install products that are tested and approved in line with AS1530.4 and in AS 4072.1 and ensure the installation matches the tested or assessed system.
- Plan the routing of services, and allow adequate space for fire stopping products to be installed. AS4072.1 requires a minimum separation distance of 40mm in between service penetrations (unless a test is conducted which confirms a shorter distance). In reality, you will often require more space than 40mm to have the passive fire stopping product installed and still be compliant.
- Call in a fire stopping professional early- don’t wait until all of the services are installed; you might be pulling them out and starting again to achieve compliance.
- Purchase your products from an expert who understands fire stopping, it will save you money in the long run.
- Fire penetrations from project to project can be vastly different. Spend time early on in the project ensuring a passive fire management plan is in place to ensure your project is not held up at practical completion because of an oversight of key minor details.
Get the right training with progressive materials, WA’s expert in passive fire protection
Everyday we see examples of both good and bad fire stopping work. The good work offers a compliant solution for the building, and the bad compromises the integrity and insulation of fire rated structures.
At Progressive Materials we are all about education for ‘best practice’ for both the installation and specification of fire stopping systems.
We offer FREE training on correctly fire sealing penetrations to Australian Standards. We can come to your office to present the training at a time that is suitable for you.
The training is best suited for:
- Architects
- Engineers
- Certifiers
- Contractors
- Plumbers
- Electricians
- Mechanical Contractors
- Builders
