Awareness of the importance of reducing embodied carbon in construction has grown significantly over recent years. A growing number of industry designers and professionals have made great strides in how to use lower carbon materials in construction, solving many technical challenges along the way, working with fellow design team members to investigate what’s possible. This groundswell of commitment has lead change, with councils now starting to pick up the importance of the issue, with a clutch around the UK now setting embodied carbon limits in their planning requirements. 

One of the key technical challenges designers have wrestled with is ensuring the fire safety of buildings using lower carbon materials, which tend to be more combustible than materials with higher embodied carbon. Taking timber as the most widely used of these, solutions such as encapsulating timber in plasterboard, or oversizing members to allow them to self-protect through charring have proved effective in addressing fire safety, with many buildings completed in the UK using such techniques.

The tragic events of the Grenfell Fire brought renewed focus on fire safety – entirely welcome and necessary in light of the legion issues identified in the investigation, and still being uncovered across the country. The element most widely publicised is the use of highly flammable external cladding; now outlawed by the building regulations, and slowly being removed and replaced across the country. However in the rush to address this risk, timber structures have been lumped in with such materials, with widespread misunderstanding about the extent of the restriction on their use resulting in a severe downturn in their adoption. This has serious implications for the drive to reduce embodied carbon, with the use of alternative steel and concrete structures continuing the high embodied carbon habits of the industry.

In fact the changes to the building regulations only restrict the use of combustible materials in the external walls of residential buildings with a floor level more than 18m above ground level. If that sounds a bit specific, that’s because it is, and as such all lower rise residential buildings (typically up to 6-7 storeys) and all non-residential buildings can still use timber in their external walls, the logic being that higher rise residential buildings have higher risk. Furthermore, higher rise residential buildings are still permitted to use timber as long as it is not in the external walls. Unfortunately this distinction has not been well understood in the industry, leading to an, unwarranted, general nervousness about using timber.

The Green Register are co-running an event – What the Building Safety Act Means for Low Carbon Construction – on Wednesday 6th November with the ASBP (Alliance for Sustainable Building Products) pulling together speakers who have been working to unlock new solutions which can continue to deliver low carbon buildings in the new fire safety context. For anyone who wants to build in low carbon materials but is unsure how to manage fire safety – this is the event for you.

The timing of the event the day after bonfire night is entirely coincidental!