President’s Column: May 2026

A burning issue

It has been a busy few months with much going on that could adversely impact our industry and requiring comment from the BCSA. At the same time, we must not forget the ongoing technical issues that impact all our members. For a long time, fire protection has been uppermost in many members’ minds, with intumescent paint systems becoming more expensive than the steelwork they are protecting. In the aftermath of Grenfell and the Luton Airport car park fire, both the required fire resistance periods and the protection systems themselves have come under added scrutiny. Much of the guidance that we are working with dates from the development of BS 5950-8 which in reality, was written a generation ago and probably overdue for some re-examination.

Many of the accepted truths from the past are now under question with a new generation requiring detailed analysis and computational proof rather than an acceptance of satisfactory past performance. One example of this is the behaviour of boundary walls in portal frames and the associated design of the capable member supporting the cladding in a fire event with new guidance published by the SCI last year. The BCSA has also set up a Fire Group acting under the P & T Committee to investigate numerous other issues, including protection of joints and requirements for coat-back on secondary members where they meet fire protected steelwork.

The basis of all this analysis is the standard fire curve, which is derived from the measured temperature of samples within a furnace over time. These furnaces are usually gas fired with a continual source of combustible fuel to maintain the intensity of the fire which is often not the case in real-world situations. In the past, this lack of correlation with real structures has allowed Building Regulations to permit some relaxation of fire ratings. The most notable example in our industry being to specify 15 minutes’ fire resistance for open-sided car parks, which in turn allows the use of unprotected steelwork. This limit is currently under review and even a slight increase in the resistance period will prevent the use of unprotected steelwork with major cost implications for this market sector.

There is also a tendency at the current time for all involved with specifying fire resistance and protective systems to play it safe. We are frequently required to justify details and situations which in the past would not have caused any concern. I had a recent example where an external platform supporting PV panels on the roof of a building was deemed to require 30 minutes’ fire resistance. A fire engineering exercise had shown that by increasing the weight of the supporting members this level of resistance could be achieved without added protection. This all looked good, however, the actual depth of the supporting members could not be increased due to planning restrictions resulting in a support structure formed from heavy column sections. The connection design was never considered during this exercise as this was a sub-contractor designed element.

However, the connection design proved to be the big issue. When considering the standard fire curve, it is found that after 30 minutes, the steel has potentially reached a temperature of 834°C with a resulting massive reduction in the bolt and weld capacities. The beams were designed as shallow depth and there is simply no space for the required number of bolts. The result is a major design problem for all involved but if we take a step back there are two basic questions. Why does the platform need a 30 minute fire rating and what is there to actually catch light and burn up there?

There is an undoubted need to update our guidance on the fire protection of structural steelwork but we should always be mindful of real-world practicality. We appear to be in a time where analysis governs all, with common sense completely forgotten and this could be the real burning issue for the future.

Chris Durand
BCSA President