Understanding fire stopping regulations in buildings

The term ‘passive fire protection’ refers to structural measures which allow occupants to safely evacuate a building, whilst also minimising damage by allowing emergency service responders to get the fire under control as quickly as possible. It is key that construction projects incorporate passive fire protection into their design. There are several examples of how this can be achieved, such as the inclusion of fire barriers, compartment walls and ceilings.

Fire stopping helps these types of installations to remain effective, by filling any openings and joints between walls and floors with fire-resistant material. Building owners, site team leaders and project managers must be aware of the regulations surrounding fire stopping best practice. Non-compliance carries heavy risks, with buildings being left with cavities, gaps, and other elements that can facilitate the spread of fire throughout a building.

Fire stopping regulations

The majority of regulations surrounding fire stopping can be found in Fire Safety: Approved Document B. These regulations apply to both residential and non-residential buildings, as well as new constructions and existing structures. They state that measures must be taken to inhibit the spread of fire where reasonably necessary. The extent of these measures will be based on the size of the building and its intended use.

Approved Document B also specifies that when constructing a new building or making material alterations to an existing one, it must be designed to prevent the unseen spread of fire and smoke within concealed spaces and in its structure. One primary way in which this can be achieved is through the installation of fire separating elements, such as compartment walls and cavity barriers.

Fire stopping ensures that any fire separating elements in a building are fit for purpose. A fire stop is defined by Approved Document B as a “seal provided to close an imperfection of fit or design tolerance”, to prevent flames and smoke from being passed throughout a building.

Complying with fire stopping regulations

A primary example of fully-compliant fire stopping is the proper sealing of ‘service penetrations’. This term refers to how pipes, ducts and cables travel through different compartments of a building, creating openings that allow a fire to spread.

The smallest gap in a compartment can render it ineffective in the event of a fire. This risk can be minimised with the use of fire-resistant sealants, pipe collars and sleeves. These gaps must not only be protected but also kept as low in number as possible.

Here are some other areas of a building in which fully-compliant fire stopping is paramount for protecting occupants and reducing risk:

• Fire doors – Fire doors are fitted to be flush with the door frame, with regulations stating that any gaps between the door and frame cannot exceed 4mm. Common fire stopping methods for closing non-compliant gaps include the application of silicone-based sealants and the installation of intumescent strips.
• Windows – The regulations for fire stopping windows are very similar to the requirements for doors. Gaps around the frame, for instance, can enable the passage of smoke. These gaps must therefore be sealed with a fire-resistant material.
• Ceiling voids – What differentiates ceiling voids from doors and windows is that the application of fire-resistant materials mustn’t affect the ceiling’s load-bearing capabilities. Gaps between floors are usually sealed using intumescent compounds, which expand to form a robust protective layer when exposed to high temperatures. These compounds also offer additional water resistance and soundproofing and can be installed at multiple depths in tower blocks or high-rise buildings.

CLM Fireproofing are industry-leading experts in all matters related to passive fire protection and fire stopping. We are committed to upholding the highest standards of workmanship, giving our clients peace of mind that their projects are fully compliant with industry requirements. To enquire about our specialist fire protection services, contact our team today.