Cladding Fire Rating Guide

Ventilated facade cladding systems can improve the thermal performance of the building and provide a wide choice of colours, textures and materials to choose from to achieve the desired aesthetic finish for the exterior construction. The cavity created between the building substrate and the cladding panels allows space for insulation and creates an air flow gap which keeps the building dry and improves the thermal performance.

It’s important to note that current building regulations state that only fire rated cladding is permitted for use on tall buildings over 18 metres in height, designed in conjunction with the positioning of fire cavity barriers, to reduce the spread and speed of flame within the cavity behind the cladding in the event that a fire reaches the exterior of the building.

Whilst most external cladding types carry a minimum classification of ‘surface spread of flame’ designed to slow and control the spread of fire, only FR (fire rated) cladding provides the higher classifications of either limited combustibility or non-combustibility. These cladding panels carry a fire classification result ranging from A1 to D in accordance with European Standards EN-13501-1.

Some cladding products quote an alternative fire classification offered by the BRE (Building Research Establishment) to their BR 135 standard, this form of testing doesn’t offer a grading as above, but tests a cladding system’s fire resistance to a specific time frame. For building regulation purposes any test using this method needs to be supported with a classification report for the proposed specification, confirming that the specification criteria of BR135 has been met.

Please refer to the relevant manufacturer product datasheets on the fire classification of the cladding product you are considering for your specification ie. Laminate, Fibre Cement, Wood Veneer, specialist composite cladding panels or other.

All the major cladding manufacturers carry out the appropriate required fire testing which results in a classification for their product, and will supply this information upon request. We recommend that you check that the cladding product you may be specifying or installing carries the appropriate cladding fire rating, required by building regulations for your type and height of building.

In addition to fire tests carried out for the cladding manufacturers at BRE approved centres such as Exova Warrington, these manufacturers also often apply for a further overall certification approval such as BBA (British Board of Agreement) or CWCT (Centre for windows and cladding technology). If the product is approved by one of these bodies, the cladding fire testing will have been assessed and will be included as part of their certificate and will be noted within the report. Always ask to see a copy of the façade cladding manufacturer’s classification report and Declaration of Performance for confirmation of compliance.

To help you understand the fire classifications, please see the table below which we found helpful in explaining the different fire classifications and what the letters stand for. (Information taken from Peroni S.p.a rev 02/2013):