New consolidated guidance from the Government’s Expert Panel made its timely appearance just before Phase 2 of the Grenfell Inquiry opened on 27 January with initial statements.
The guidance is for building owners of high-rise residential blocks, though its principles apply more widely. It stresses that resident safety should always be an urgent concern.
The focus is on cladding systems and the risks of fire spread over external walls. But owners are also reminded to assess all fire safety risks. They are advised (in effect directed?) to take steps to understand the building construction and its likely behaviour in fire.
Grenfell Phase 2, as well, is expected to focus in a forensic legal way on responsibilities.
That concerns decisions taken along the budgeting, design, specification, supply,construction and building management chain for the main products and product systems that Phase 1 concluded were major contributors to the violence of the fire.
Attention in Government guidance is also drawn to the risks of fire spread via windows, mentioning the surrounds, given that windows are an important element in any façade (and a factor in fire spread to the interior on floors above the initial fire break out).
It should be understood that normal window glazing does not have significant resistance against fire, including standard double glazing.
Glass products that are not specifically fire resistant readily fall apart in fire; and there is clearly a distinct risk of fire transfer both from the inside to the façade and from a burning façade back into the building through a window opening created when glass falls out.
Special fire-resistant glass and glazing systems are necessary to limit the risks of fire spread through windows – though UK practice does not make best use of f-r glazing in that way to limit the chances of fire spread by break out and then break back in from a burning façade.
Yet fire-resistant glazing is well-established for various internal applications, for many decades. It’s a common product, readily available and easily sourced. Fire-resistant glass used in the façade does not need to be particularly sophisticated: just integrity fire resistance performance would be enough to maintain effective containment.
For example, ceramic glass at only 5mm thick is immune to thermal stress. It can happily survive in fire conditions (uniquely) at such a thickness even when impacted with a firefighter cold hose stream, typically demonstrated after 4 hours’ exposure in a full-on standard fire test, sprayed on the hot face. That is a particularly significant benefit.
Glazing solutions are already available to reduce the severe risks of fire spread from inside to outside and from outside back inside. They just need to be specified and implemented.