Cladding is not in itself the enemy. As a construction material, it is applied over another to provide a skin or layer, and is used to provide a degree of thermal insulation and weather resistance. It also has aesthetic benefits, as it can improve the appearance of buildings. Between the cladding and the wall there is a cavity where rain can run down.
The tragedy of Grenfell in 2017
Many factors contributed to the catastrophic results of the fire, three of which need to be considered for every retrofitting cladding or facade project: the cladding material used, the risk of fire spread and inadequate fire safety measures.
The problem is that the Grenfell Tower was clad with an aluminium composite material (ACM) panel, with a highly flammable polyethylene core. Alongside this, the cavity barriers intended to prevent fire spread in the ventilation gap were insufficient and, in some cases, incorrectly installed. The final issue was that there were inadequate methods to tackle the fire within the building, including a lack of sprinklers and only one escape route.
Immediately post Grenfell
An urgent review of the fire safety and building regulations was conducted by Dame Hackitt in 2018 and desk top studies to evaluate fire protection were phased out, which left many practices in a quandary as to which products and combinations they could specify. Many common products that formerly specified for taller buildings could no longer be used, such as certain cavity trays or timber decking to balconies, as they are combustible. This left a significant hole in the industry until manufacturers could catch up with the demand and supply of new products that were safe to use. Many building materials also needed to be retested, leading to further delays in product availability for taller buildings.
The introduction of the Building Safety Act
In July 2020, the UK parliament introduced the Building Safety Act, which came into force in April 2022. Changes promised clarity in building standards and guidance and improving the competence of the people responsible for overseeing, managing and delivering works to higher risk buildings. The term for higher risk buildings was later defined in 2023 as generally for those that are 18m or seven stories high or more and that have two or more residential units. There have since been further definitions that include care homes, refurbishments, hospitals and hotels.
The three ‘gateways’ were also introduced that apply from the initial planning stage to the construction phase and post occupation, and whereby the industry must fulfil certain criteria in order to pass each gateway. Only once passed, can the building be register with the BSR (Building Safety Regulator) for occupation.
The Golden Thread
Gateway 1 covers the design stage, and became effective from August 2021, during which the BSR reviews planning applications before planning permission is granted, to establish that building designs adequately address fire safety.
Gateway 2 is for the Preconstruction stage, covering a 12-week determination period, which became effective in October 2023. Building work cannot commence until the BSR approves the building control approval application and assesses whether the proposed design meets the requirements of the building regulations.
Gateway 3 is for Occupation, and came into effect in October 2023, with an 8-week determination period. This specifies that the building cannot be occupied until the BSR makes an assessment of the totality of the build, to ensure it complies with regulations and thereby issues a completion certificate.
These gateways have created new roles in the form of a BSR, who now decides building applications instead of local building control or approved inspectors. Accountable Person(s) such as the building owner, freeholder, or management company will have an ongoing responsibility to assess the building’s safety risks and to provide a ‘Safe Case Report’ which shows how building safety risks are identified and managed on an ongoing basis.
Determination periods for Gateways 2 and 3 will and are having an impact on the construction industry, as the law is being applied and the industry will no doubt continue to adapt as companies that build become more resilient.
BSR future plans
The BSR will continue to take action on noncompliant cladding, having to date already assessed 40% of occupied higher risk buildings. When it comes to whether recladding is required, then for the most part, the aim is to replicate the original facade design and colouring as closely as possible, in order for the recladding to gain planning permission. Improvement usually occurs in thermal performance and fire protection.
Performance indicators are continually being reviewed and assessed, to consider what further action or guidance may be needed, regarding stairs and ramps in relevant buildings, emergency egress for disabled persons and automatic water fire suppression systems.
There is a long way to go, but the signs are encouraging, in spite of this most recent incident.
