The Impact of Hackitt on Concrete Frames
21 Aug 2018
On the 14th of June 2017 the Grenfell Tower caught fire. The fire spread exceptionally quickly through the external cladding system. In addition to the unanticipated fire spread a number of other fire safety features did not perform as intended. Since the fire a criminal investigation has been instigated, a Public Inquiry is taking place and there have been three consultations on aspects of fire design. One of the first studies carried out was an Independent Review into Building Regulations, led by Dame Judith Hackitt. Her final report with 53 recommendations was published on 17th May 2018.
The immediate press coverage and political conversation following the report publication was about what it did not do: it had not recommended the banning of combustible cladding and it had not recommended compulsory sprinklers. Dame Judith claimed that was never part of her brief and that she was tasked with a much more high-level review of the building regulations.
So, what does the report say? It claims that our building regulations and guidance in Approved Documents is not fit for purpose, enforcement is inadequate and that the means of demonstrating competency in the construction industry is inadequate. To address these, Dame Judith Hackitt recommended the creation of new structures: a structure to validate and assure guidance, a Joint Competent Authority (JCA) to deliver rigorous enforcement and an overarching body for competency. As part of the enforcement a far more rigorous testing and labelling regime was proposed.
This note looks at the potential impacts of the report’s recommendations on concrete frame construction.
Scope of application
The report limited its recommendations to High Risk Residential Buildings (HRRBs) which it further defined as Residential buildings over 10 storeys in height. This building type is seen to have the highest risk to life safety. There are many recommendations that Hackitt suggested could be applied to other building types in due course. However, whilst the systems are being developed prioritising HRRBs initially is reasonable. It should be noted that the subsequent consultation on combustible cladding used a building height of 18m (approx. 6 storeys) as its limit and others have called for much wider application of the recommendations. What is clear is that even if the recommendations are initially only applied to HRRB’s they are likely to be applied more widely once the systems bed down.
While the review overall was primarily concerned with Fire Safety, in many cases the report discusses the “Building Safety”. In various presentations Hackitt has noted that the recommendations should be applied to all safety elements. Indeed, in July 2018 the Secretary of State for Ministry of Housing, Communities and Local Government announced the creation of an “Industry Safety Steering Group” to be chaired by Dame Judith Hackitt, confirming the wider remit than just fire.
Whilst the report did not “ban” combustible materials there are strong references to discourage its use. In noting the different layers of protection required it states “the use of non-combustible materials throughout the building” provides inherently higher levels of protection. Later in the report “Using products which are non-combustible or of limited combustibility is undoubtedly the lower risk option.” Concrete as a non-combustible material can therefore be considered the low risk option. It is likely that the results of the government consultation on combustible materials in the cladding zone will be presented in November. It is expected to support a ban of some form.
Joint Competency Authority
Hackitt proposed the formation of a new Joint Competent Authority (JCA) comprising Local Authority Building Standards, fire and rescue authorities and the Health and Safety Executive. The JCA will be responsible for assessing the project at various gates. For example, prior to the start of construction: “the Principal Designer is formally required to present the JCA with Full Plans. This should include dutyholders providing detailed specifications of building works in respect of fire and structural safety as a minimum”.
If this recommendation is to be applied rigorously it will require significantly earlier involvement of specialist sub-contractors particularly regarding passive and active fire measures, but also regarding structural details.
Any changes to the submitted plans and details of how the building’s construction compliance with the original design was verified is then reviewed by the JCA and will need to be passed prior to occupation of the building. There is likely to be a greater focus on the accuracy and, indeed, content of as-built drawings, with recommendations of a digital record that would include traceability of the products used as discussed below.
There is also the proposal for the JCA to carry out periodic reviews of occupied buildings. In these reviews the dutyholder will need to demonstrate that they have considered, controlled and managed any risks that arise. In older buildings damage to fire protection due to unauthorised or accidental actions must be considered a risk. Effectively the proposal is to extend CDM through to safe occupation.
Concrete, with its in-built, robust, passive fire protection, is a low risk solution for JCA approvals both during construction and after occupation.
Testing and Labelling
The text in the Hackitt report specifically concerned with testing is largely aimed at the fire industry. However, as the remit of the JCA will include all safety critical elements, it is likely the same criteria will be applied to structural products. The concrete industry already has systems for testing structurally critical products and providing 3rd party accreditation of ongoing compliance such as those operated for reinforcement products by UKCARES. Perhaps potentially more controversial are the recommendations made on labelling. Hackitt advocates the following requirements for the labelling system:
- A description of what the product is.
- A description of what the product can be used for
- A method for the producer to ensure that their product is used in accordance with any limitations expressed in 2.
- A method to identify the product for potential recall.
It is hard to see how requirement 3 could be applied to a generic material such as reinforced concrete and even for other products it is not clear how such a recommendation could be implemented. Requirement 4 is largely related to traceability. This combined with the proposed digital record may be the push that makes digital labelling of reinforcement and other related products the norm. It is also worth noting that currently the concrete industry already has schemes that provide an audit trail from the original materials through to the site. In addition to UKCARES for reinforcement there is QSRMC/BSI for concrete. The effectiveness of the later systems was demonstrated some years ago when a cement plant was found to have produced non-conforming cement. It was possible to track this cement down to the specific delivery to site. Where accurate site diaries existed, it was then possible to locate the affected concrete within the structure. The digital record should allow this final step to be formalised and the information better kept in the future.
The report calls for a consistent way to assess competency. It notes the work already started to create an industry wide body with oversight for competency. The report then states that if industry cannot agree an appropriate competency framework then government should mandate a body to do so. The recommendations in the report are largely concerned with fire. However, the JCA will need to be convinced of the competency of others carrying out safety critical tasks so it could be expected that the final competency framework developed will need to include aspects of structure. Clearly understanding the levels of competency required, and how these relate to current qualifications within the industry, will be key for those who wish build structures for HRRBs.
The Building Regulations
The report calls for a “regulatory framework featuring clear outcomes”. In the main it is understood that the report is calling for an overhaul of the Approved Documents. The Building regulations themselves are largely outcome based, but the concern expressed is that the Approved Documents then replace these outcome based requirements with prescriptive rules. It is likely that some prescriptive rules will need to be retained, particularly for buildings not in the HRRB sector. For concrete structures it seems unlikely that requirements will change significantly from compliance with the Eurocodes. However, it is conceivable that more focus may be placed on linking the building use, competency and safety factors, which is part of the Eurocode basis of design.
Whilst the Hackitt report is primarily concerned with Fire Safety the recommendations are likely to be more far reaching. Structural Safety will probably fall under the same framework. It is also likely that the recommendations will be applied significantly wider than residential buildings over 10 storeys. The industry should welcome the recommendations favouring non-combustible materials. The principals of the Joint Competency Authority to enforce regulation are generally positive however certain aspect of the gate process may require refinement. Similarly, there are certain aspects of the proposals on testing and labelling that would be difficult to implement within the concrete frame market. However, the concrete industry already has systems in place that address much of the recommendations. The use of digital labelling and formal traceability of products in the final structure will need to be developed. There will be a focus on competency for those designing and constructing buildings that fall under the recommendations. It is not yet clear how this will compare to current practice, but it is unlikely that the design of concrete frames will be significantly affected by the reports proposed review of regulations.