Embodied Carbon: How can we make it happen?

Wood for Good’s LCA database launch was first event during Embodied Carbon Week in April. Here Gary Newman, executive director of ASBP, discusses why embodied carbon could be included and assessed within building regulatory frameworks.

The motion under debate was should embodied carbon be included within zero carbon definitions. The motion was carried; but there was a swing away from the motion. I spoke in favour of introducing embodied carbon into the definition at the earliest possible opportunity in 2019. However, during the debate, I found myself shifting position. Not so much in favour of delaying the introduction, but more towards a position that the zero-carbon definition is perhaps the wrong place to regulate embodied carbon.

It should be re-stated that the ASBP is totally committed to re-balancing the construction agenda through increased focus on resources, materials and products and on how they are deployed in construction. We think the wins are substantial – and there are increasing signs that the wider industry is beginning to recognise this opportunity. However, when it comes down to the details of how best to drive change, and the question of appropriate policy, things get a bit more complicated. So is the zero-carbon definition the right home? The thinking behind including embodied carbon in the zero-carbon definition is simple and based upon the fact that embodied carbon is a substantial and growing proportion of the overall whole-life carbon impact of a building. And therefore, an aim to achieve zero-carbon must include embodied carbon.

However, the zero carbon agenda was conceived around operational energy reduction and embodied carbon has come to the table relatively recently. Is it sensible to combine both operational carbon and embodied carbon in one regulation? I’m not sure, as they are very different beasts. Also, we should surely be striving to reduce both operational and embodied carbon and not be trading one off against the other, as may well be the case if we combine in one overarching regulation.

In some cases a strategy to reduce operational carbon may lead to an increase in embodied carbon – and in that sense they are linked. But I suspect that in most cases they are not really linked to any great extent. Good design to reduce operational carbon through, for example, a focus on detailing to reduce cold bridging and increase air tightness may have little or no impact on embodied carbon. A policy to design for deconstruction could have a profound impact on the reduction of resource use in buildings and consequently on embodied carbon, but have little impact on operational carbon.

For embodied carbon to be included in the zero carbon definition it would need to be included in Part L of the Building Regulations. Is such a revision to Part L practical as a short, medium or even long term aspiration? I’m not sure. Regulating embodied carbon through building regulations must surely be a medium term game at best, and if such an approach fails, it could stand in the way of other potentially more fruitful courses of action.

Should we put all our embodied carbon eggs in one Building Regulation basket? As UKGBC pointed out, in today’s political environment of reducing regulatory burden on industry and cutting ‘red tape’ a push for new regulation on embodied carbon is unlikely to get much traction. So what other options are there?

In the short term a voluntary standard could be developed. Something akin to Passivhaus perhaps? A low embodied carbon house, might have greater social and environmental benefits than a low energy house, but perhaps not the same consumer appeal. Such a standard would probably therefore need to be driven forward by the public sector. The soon to be published RICS embodied carbon methodology could form the basis for this standard. A ‘RICS embodied carbon excellent’ building perhaps.

A nationally described standard with practical application in the planning process could be developed. Such standards exist for access and minimum space requirements, why not for materials and embodied carbon? The ASBP argued the case for a nationally described standard for materials in our contribution to the housing standards review.

Many organisations are developing Environmental Product Declaration and BIM driven design tools. These will enable design for low embodied impact. Clients can require embodied impact to be considered early stage in the design process. But such an approach could develop more quickly if set within the context of a voluntary or planning standard.

The UKGBC embodied carbon week was extremely successful. However, feedback suggests that the product sector (the sector that can do most to reduce embodied impact of construction) was less engaged. This may be in part due to the fact that embodied impact does not currently matter, and the voluntary standards which draw on the Green Guide to specification provide little incentive to the supply chain to innovate to reduce embodied impact. Such a market failure would support the view that, in the absence of regulation, a new voluntary standard is needed alongside the development of transparent non-generic alternatives to the BRE Green Guide to Specification.

Perhaps embodied carbon could be dealt with as an Allowable Solution. There is increasing data available to enable embodied carbon benchmarking for building types (such as the WRAP embodied carbon database) – so a reduction from such benchmarks could be deemed an allowable solution. This holds out the potential for substantial and rapid embodied carbon reduction in new build housing.

BREEAM and LEED could be strengthened to make embodied impact consideration a compulsory element for a high rating. One simple requirement that buildings over a certain size should be designed for deconstruction could have a profound effect on embodied carbon reduction and support resource efficiency and help to realise some of the gains associated with a move to a more circular economy.

A focus on Resource Efficiency would certainly bring substantial embodied carbon gains. It seems likely the targets will be coming out of Europe and will perhaps drive change in a similar way to the Energy Performance of Buildings Directive. It must certainly be true that if we are going to realise the wins associated with the circular economy, strong legislative drivers from Europe will be required.

But perhaps the best way to reduce the embodied carbon of our built environment is through the tax system. Working on the ‘follow the money’ principle, if embodied carbon were to be taxed in some way, there would be a strong incentive keep the bill as low as possible. Such an approach would appear to be much simpler than an addition to Part L.

So the possibilities to drive change are plentiful. We know from recent history that market mechanisms were not sufficient to drive energy efficiency and we can confidently predict that they will not be sufficient for resource efficiency and embodied carbon reduction. The debate now needs to move on from the question of why, to how.