Fire Compartmentation in Buildings

Fire compartmentation is a key principle of Passive Fire Protection (PFP). Instead of actively putting out fire, PFP measures aim to limit the spread of fire and smoke within a building. This in turn has numerous beneficial advantages; from reducing the damage caused by fire to infrastructure and people, to increasing the amount of time people have to escape the building. Critically, PFP measures save lives, facilitated greatly by the effective compartmentation of buildings.

At CPFP we provide expert accredited PFP services for a range of proven solutions, all centred on compartmentation of buildings. From fire door installation to cavity barriers, we always consider the spread of smoke and fire, and find effective ways to reduce it. In this blog we explain what fire compartmentation is, how it is achieved, why it is important, and how we can help your building become compliant and safe.

See more: Structural Fire Protection – Structural Measures to Prevent Spread of Fire

What is Fire Compartmentation?

Fire compartmentation is when a building is divided into sections and sub-sections that are all independent of each other. In the event of a fire, it means that fire and smoke are contained within the sections it originated in or initially spread to, limiting spread and damage. By utilising walls, floors, ceilings, and integrating smart design, buildings are effectively divided.

Confining fire and smoke to a singular space has many benefits including allowing for adequate time for safe evacuation.

What is a Fire Compartmentation Survey?

When you have a fire risk assessment on your building (a mandatory requirement for many commercial premises), it is possible that the Fire Assessor may recommend a Fire Compartmentation Survey is undertaken. This would be recommended if the assessor feels that there are numerous breaches of compartmentation walls, floors, or ceilings that may be susceptible to leakage in the event of a fire. It involves intrusive inspection of ceiling space, floors, and other void spaces to assess whether the compartmentation elements could do an adequate job at preventing the spread of fire and smoke for long enough to enable escape.

How Does Fire Compartmentation Work?

Designed and built into the building, fire compartmentation must be considered and planned early for optimised effectiveness. As fire compartmentation works by separating areas within a building, it must be carefully constructed and consider the placement of walls, floors, and ceilings.

Any aspects involved in compartmentation edges, like walls and floors, must be adequately fire resistant. Also, any additional elements to these, such as handles and hinges, must be equally fire resistant.

Doors in compartmentation walls must be fire doors, preventing a point of possible weakness or escape for fire and smoke. Other PFP methods are employed too, as explained further below.

Why is Fire Compartmentation Important?

Slowing or even stopping the spread of smoke and fire is critical to keeping people alive and preventing serious damage to entire buildings. This is especially pertinent for buildings where there is a ‘sleeping risk’ – care homes, apartments and hotels – whereby people within the building may not be awake or alert if a fire did occur.

What are the Common Causes of Workplace Fires? >

There is a legal need for fire compartmentation; Building Regulations Approved Document B demands as a minimum that the design of a building ensures there is time for people to escape safely in the event of a fire. Fire compartments help to slow the spread and maximise time to escape safely. More information can be found in Section 5 – Compartmentation.

How is Fire Compartmentation Achieved?

Aside from the plan and design of a building, there are numerous ways fire compartmentation can be achieved with popular PFP measures.

Fire Doors

Regular doors cannot be used within compartment walls, and instead doors on a compartment perimeter must be fire doors. These doors are designed to withstand fire for a certain time, prevent seal leakage, and close automatically. Find out more with our blog: Fire Doors Explained.

Approved Document B says the following about compartment doors:

7.19 Openings in a compartment wall common to two or more buildings should be limited to those for either of the following.

1. A fire doorset providing a means of escape, which has the same fire resistance as the wall and is fitted in accordance with the provisions in Appendix C.
2. The passage of a pipe that complies with the provisions in Section 9.

CPFP are accredited with the IFCC to install fire doors, ensuring a compliant, effective fit. Our experts work with clients to install and maintain fire doors to the highest industry standards, matching the requirements of individual buildings.

View our fire door services >

Read more: Fire Door Regulations – Fire Door Regulations Explained

Penetration Sealing

Any penetrations in compartmentation walls must be properly sealed to prevent leakage of fire and smoke through gaps. Penetrations may include pipes, cables, ducts, joists and more. Penetration sealing is achieved by using intumescent mastic, mineral wool boarding, and other fire-resistant materials to fill cavities created by penetrations.

Cavity Barriers

Cavity barriers are specially designed and created to prevent the spread of smoke and fire within void spaces of cavity walls, floors and ceilings, where fire would easily spread if unencumbered. These barriers, made up of fire-resistant materials, facilitate the effective compartmentation of buildings by ensuring fire is contained within compartments.

Read more: Cavity Fire Barriers – A Beginner’s Guide to Cavity Fire Barriers

Within the Building Regulations Approved Document B, the requirement of cavity barriers in relation to compartmentation is as follows:

5.18 Cavity barriers should be provided at all of the following locations.

1. At the edges of cavities, including around openings (such as windows, doors and exit/entry points for services).
2. At the junction between an external cavity wall and every compartment floor and compartment wall.
3. At the junction between an internal cavity wall and every compartment floor, compartment wall or other wall or door assembly forming a fire resisting barrier

Find out more about the cavity barrier services provided by CPFP >

Achieve Effective Fire Compartmentation with CPFP

CPFP offer expert PFP services, third party accredited with the IFCC, from fire door installation to cavity barrier maintenance helping clients achieve effective fire compartmentation in their building. Our experienced team have installed PFP measures to hospitals, offices, residential buildings, hotels, retail premises and more across the UK.

For help achieving compliant and safe fire compartmentation in your building, get in touch with our expert team at CPFP!

See more: How to Find Out if Your Passive Fire Protection (PFP) Provider is Certified

See more: Passive Fire Protection Regulations, Standards and Accreditations