27 February 2020

TRADA seeks members’ views on the proposed tighter ban following Grenfell

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The Ministry of Housing, Communities and Local Government, the government department responsible for Building Regulations, launched another fire-related consultation on 20 January 2020, as TRADA reported last month.


To summarise, the following three proposals within the latest consultation have the greatest potential impact on the timber supply industry: that hotels, hostels and boarding houses be included in the definition of those building types which would be impacted by the ban on combustible materials; that the height threshold of the ban should be reduced to a minimum of 11 metres and above; and that solar shading products should achieve Class A2-s1, d0 or A1.


Everyone understands the need to take appropriate action in order to ensure that something like Grenfell doesn’t happen again. It is, therefore, very important that we fully understand the root causes and ensure that we have sufficient evidence that proposed changes to regulatory requirements will address these root causes.


TRADA’s key concerns with the approach being taken by the Ministry of Housing, Communities and Local Government


1. The mixing of our now long-established functional approach with a prescriptive approach.


We moved over to a functional approach to building regulations in 1985 and it has stood us in good stead. Mixing two different approaches is generally inadvisable, as engineers will know when they transitioned from the former British Standard approaches to the Eurocodes. All sorts of loopholes, unintended consequences and irregularities are created if you are not careful. This topic is discussed in some considerable detail by Angus Law, BRE Lecturer in Fire Safety Engineering, University of Edinburgh, and Neal Butterworth, Director of Design Fire Consultants, in an article published by ICE entitled Prescription in English fire regulation: treatment, cure or placebo?


2. Changes not informed by evidence.


TRADA understands that, for many years, significant changes to specific aspects of the building regulations have been informed by appropriate research – whether it be desk-based or physical experimentation – to confirm that any changes made are justified and proportional. The changes announced in this latest consultation are stated within the consultation itself to have not been researched, and that this is intended to be undertaken later.


The consultation asks for evidence by anyone suggesting tighter or looser recommendations than the ones proposed – but there is no evidence or methodology to justify what is being proposed. It is, therefore, not possible to properly conduct this debate now or in the future when we are considering other changes that become necessary. Like a good building, our regulations must be based on sure foundations in order to stand the test of time.


3. The approach taken has created a number of very significant unintended consequences.


One of these is that there are now many buildings that were compliant with Building Regulations at the time of being constructed a few years ago but which now appear to be judged by others to be ‘unsafe’. Whilst there is no requirement under Building Regulations to retrospectively upgrade these buildings, other factors such as mortgageabilty and insurability have had a very big impact on residents in medium-rise developments, for example.


4. The references and use of the Scottish approach is confusing and out of alignment with how the 11 metre trigger threshold for non-combustible materials is used in Scotland.


The Scottish approach, as defined in section 2.7 of the Scottish Building Standards Technical Handbook, uses an 11 metre threshold as a backstop position. It allows a higher threshold where either:

  • provision acceptable to the fire service is made for fire appliances with greater reach; or
  • test evidence for the overall cladding system to BS8414 (a functional approach previously permitted within the English regulations) proves the suitability of the system. In addition, the Scottish Standards only require non-combustible materials on the external and internal surfaces and not the structural members.


Overall, this seems a more proportional and functionally-based response than what is being proposed for England.


TRADA intends to respond to this consultation and we are seeking members’ views on these important proposed changes. If you are a member, we will write to you separately with a draft response for you to comment on. We would encourage all those concerned about protecting the responsible use of renewable building materials such as wood to respond in their own right.


Further reading

Prescription in English fire regulation: treatment, cure or placebo? – ICE article written by Angus Law, BRE Lecturer in Fire Safety Engineering, University of Edinburgh, and Neal Butterworth, Director of Design Fire Consultants