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Fire stopping, also known as compartmentation, is a fundamental part of passive fireproofing. It refers to the process of filling openings and joints between walls and floors with fire-resistant material, inhibiting the spread of fire between ‘compartments’ within a building.
In this post, we’ll explore the origin of fire stopping regulations in construction. We will then provide an overview of the most common fire stopping methods, as well as some of the most frequent instances of non-compliance with industry best practice.
Compartmentation and fire stopping originated in the shipbuilding industry. Similar to the construction industry, the walls were often peppered with holes to allow ducts, pipes, and cables to pass from one area to the next. Fire stops were meant to stop fires from penetrating and travelling through these gaps. While used for construction on land it would be some time before regulations regarding fire stopping materials and requirements would be put in place.
The pivotal moment came in March 1975, when a test was performed at the Browns Ferry Nuclear Power Plant using a lit candle. The goal was to discover air leaks, but the polyurethane foam used at the time turned out to be highly flammable. The fire quickly spread, significantly damaging the reactor control cabling. That was considered a significant moment in the use of fire stopping in the nuclear, commercial, and industrial construction fields.
CLM Fireproofing is the UK’s leading specialist provider of passive fire protection services, specialising in fire stopping and fire doors, compartmentation and penetration sealing.
Another catalytic event was the MGM Grand Hotel Fire in Las Vegas. Commonly considered one of the worst fire-related disasters in U.S. history, 85 people lost their lives and over 600 people were injured. In the aftermath of the fire, it was discovered that one of the main reasons the fire spread so quickly were unfilled openings in joints, electrical and plumbing systems and vertical shafts. The changes in passive fire protection best practice following the fire formed the basis of the numerous fire stopping regulations that companies and contractors abide by today. These include:
There are various methods, materials, and products used for fire stopping. Depending on the construction requirements and environment, these may differ. Below, we look at a few common methods and products and when they’re typically used.
Pipes and cables can pass through different ‘compartments’ within a building. The openings around their entry and exit points between compartments can act as channels for fire to spread. To prevent this from happening, passive fireproofing professionals have a variety of tools at their disposal.
Fire sleeves are fire stops made for sealing the gaps created by pipes and cables passing through walls or ceilings. When there’s a fire, these sleeves expand rapidly to seal the space between the pipes or cables and the surrounding materials. If used with plastic pipes, the sleeve will crush the pipe to ensure that the gap is fully sealed and that no smoke or fire can travel to the next area.
Similar to fire sleeves, fire collars expand under the high temperature of a fire. These collars help maintain fire resistance levels in conjunction with other fire stops and prevent gasses or flames from spreading from one compartment to another.
These covers are designed to stop fires in ceilings. Should a fire occur, the cover will immediately begin to expand internally and fill an entire space with a fire-resistant, insulating char.
As the name implies, fire sealants and gap fillers prevent fire and smoke from spreading through spaces. When heated at high temperatures, these fire stopping materials expand. There are various sealants and fillers, and it’s critical to use whatever one is best suited to the substrate and application.
These firestops can be used around pipes and cables, as well as fire doors and windows. Although fire doors are fitted to be flush with the door frame, any gaps between the two are filled with silicone-based fire-resistant sealing. To enhance their fire resistance, intumescent strips are often attached to the base of the door.
For fire stopping purposes, windows are treated in a similar way to doors. Gaps around the frame are sealed with a fire-resistant material (suitable for the particular substrate), and any cavities around the window space are filled with a thermal cavity barrier (more on this below).
Despite a similar purpose, cavity barriers and fire stops differ in their applications. Cavity barriers are designed to effectively close a cavity between two building elements, such as between a floor slab and cladding materials or a loft space. On the other hand, fire stops are intended to close a service penetration made through a compartmentation element, such as a pipe going through a firewall.
While there are fire stopping regulations in place, there are still common mistakes that can lead to a failed fire safety inspection. It’s critical to ensure that the correct fire stopping materials and installation protocols are followed. The four most common fire stop mistakes are:
Of course, the biggest mistake is when a construction contractor tries to circumvent regulations and avoid installing a fire stop. That still occurs today and can have serious repercussions. Obviously, installing testing and approved fire stops are necessary for the safety of those using the building.
Fire stopping is an essential component of a building’s safety. They’re required to help prevent the spread of fire through the different compartments of a building. Without having fire stops correctly installed, smoke and flames can quickly travel through a building, damaging the property and risking the lives of its occupants. Fire stops also help emergency services to suppress the fire before it spreads beyond control.
Once installed, fire stopping measures need to be monitored regularly and assessed for their effectiveness. Failure to do so could mean that your property is not in compliance with current fire safety regulations, and you could be held accountable in the event of a fire.
Always ensure that the correct fire stopping materials are used and that materials and expertise are supplied by reputable fire stopping companies.
CLM Fireproofing is one of the UK’s leading fire stopping companies. With 35 years of experience, our experts are able to accurately assess fire risk in your buildings and install measures to ensure full compliance with current regulations. If you’d like to know more, get in touch with CLM Fireproofing today.
Disclaimer: This post is intended for educational use only, and should not be relied upon for compliance purposes.
Fire stopping, also known as compartmentation, is a fundamental part of passive fireproofing. It refers to the process of filling openings and joints between walls and floors with fire-resistant...
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