John Gardner, National Specification Manager of fire stopping specialist FSi Promat, looks at how single-sided fire stopping can support project efficiency.
09 December 2025
While standard passive fire protection systems work by forming a fire-resistant barrier to stop fire spreading from one area to another through applying the system on both sides, a single-sided solution can achieve the same fire resistance but by only being applied to one side of the wall. John Gardner, National Specification Manager of fire stopping specialist FSi Promat, looks at how single-sided fire stopping can support project efficiency.
Access can be a considerable issue in refurbishment projects, with often only one side of an application being accessible due to either the physical location of the seal, or to avoid the costly displacement of residents if the building is occupied.
As a recognised problem, specific solutions have been created to accommodate this, with fire-stopping systems now available for a single-sided application. FSi Promat has recently tested a selection of its fire-stopping systems in various common service configurations, which allow a compliant seal to be put in place to reinstate compartmentation without the need for access to both sides of the wall.
It is vital that buildings being retrofitted for a change of use have the correct specification of passive fire protection.
Multiple-occupancy buildings demand the highest level of passive fire protection to ensure occupants have time to escape in the event of a fire – and that the integrity of the building is protected to allow firefighters access in the event of a fire. The switch to a residential property is likely to see the time resistance of passive fire protection increase and any change of use must incorporate the level of fire protection specified in its fire strategy document.
Whatever the scale of the project it is essential that any changes to services, such as pipes and cabling, and to windows, doors and air vents – as well as to the fabric of the building – take into account the need to reinstate compartmentation through adequate fire stopping.
Fire stopping is required in all service penetrations where compartmentation is in place, which means that any upgraded services will need to be adequately fire stopped to ensure compartmentation remains intact. The same applies to any alterations to fire doors, windows or façades, and any additional breaches onto the compartment walls to facilitate access. They must all have a compliant fire-stopping seal.
This is further complicated in retrofit projects by the element of the unknown as to what passive fire product has been used previously, and when it was installed. If there is no record of the installation, the fire stopping will need to be replaced to ensure that the passive fire protection in the building is compliant. The building owner still needs to ensure the requisite fire safety systems are in place - and if there is no record in place that will prove impossible.
Further to this, mixing existing, older passive fire protection with new is prohibited due to evidence not being available to clearly demonstrate the installation and product details, meaning that the tested solution for fire stopping in that application may not be supported as the full details cannot be verified – and so, the whole system will need to be replaced.
Another major challenge around retrofit projects is working in a building that is already occupied.
The single-sided fire-stopping systems from FSi Promat bring a huge benefit to residents, planners, and contractors, as there is no need for occupants to vacate properties during the works, causing minimal disturbance and avoiding high displacement costs. Areas with restricted access
Single-sided solutions are also ideal for areas where access to one side of the wall is limited or restricted, for example, if services run above a rigid ceiling that would require destructive work to access the compartment line, or back onto shafts or risers where you cannot reach the other side of the wall – again, saving time and reducing complexity of a project.
To find out more about the single-sided application fire-stopping solutions available from FSi Promat, visit its website and download the Quick Selector, which includes all of the standard details.
Find out more about the solution here, and if you have a project enquiry, get in touch with the team.
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