This is the single biggest minefield within the fire industry. The sheer mention can cause the most confident professional to run for the hills.
It doesn’t have to be this way though. Firstly, what is the difference? A facade is the elevation of the whole wall itself including windows and doors etc. Cladding is the material used to treat a vertical surface, such as brick, metal profile, Rainscreen etc. The purpose of cladding is to protect a building’s structure from elements like wind and rain, but it can have other benefits, such as, insultation, noise control and it can boost the aesthetic appeal of a building.
As previously stated, cladding is designed to protect the building from the elements. This requires a ventilated cavity to enable the materials to not perish under the elements. A concealed cavity in the external wall of a building can act as a chimney and provide an easy route for flame, hot gases and smoke to propagate from one compartment of a building to another. Unsealed cavities can allow air to be drawn in and smoke to vent out, enabling the fire spread to accelerate through the façade. This chimney effect enables flames that are within a cavity to be able to extend between 5 and 10 times higher than a flame that is not within a cavity, regardless of whether the surfaces of the cavity are combustible or not.
To allow for this there are numerous methods with the two predominant methods being the use of cavity barriers and fire stops. Essentially the biggest difference between them is a cavity barrier is designed to seal internal gaps within walls, ceilings and other parts of a building. By contrast, fire stops are intended to seal visible, external gaps between them that are caused by imperfect fittings.
The primary function of any of the systems is to maintain continuous ventilation and drainage behind cladding whilst providing a hot smoke and fire seal if triggered.
Considerations when selecting a system
Ultimately the selection and correct installation of a system can potentially save people’s lives. It is therefore a decision that should involve qualified parties to ensure effective systems are specified. All buildings are different, and it is important to consider not just the product, but also the environment and situation into which it is being installed. Each construction situation can be different, so simply using the same system used on a previous project may not be the answer.
With the huge range of products that are now required by building regulations, it can be difficult to understand which one is required. The simple answer is all of them. A functional system is only made when a combination of products are all working together. Without the use of one single product, the rest of the system could fail.
How IMS can Assist and our expertise in retrofits.
Unfortunately, no two projects are the same and as more inspections are completed on buildings it is evident that not all systems were designed correctly or installed as per the original design.
IMS Group has vast experience in assisting our clients regarding remediations of systems behind the cladding from both inside and outside of the building. We work with our clients, inspectors and manufacturers technical departments to offer the best solution for each project. Each project is treated as an individual entity as we know from experience that there is not a single answer and numerous factors are required to select the correct system to ensure the building acts as it was originally designed in the event of a fire, such as:
- Disturbance to the occupancy of the building
- Overall Risk level
IMS Group are happy to work in partnership with all bodies to install a system agreed by all parties.