I want to talk about materials and life cycle assessments (LCA). I’m not a specialist in the area, but I am a sustainability professional, and for me this is an area where we (as the construction industry) can have a huge impact for the better.

The impact of a building in operation is broadly understood by a building owner. They have to pay the water bill, the gas bill, and the electric bill, and so they can see the consumption uses of the building first-hand. But what about the embodied impacts of the building? 

Do building owners think about the energy that went into the extraction of the materials that go into the building? Or the water used in the raw material processing? Or what impact the building will have at the end of its life, when all its constituent parts are disposed of? I’m sure some do, but I suspect a lot do not. And I can understand why – for a layperson these invisible costs can seem quite intangible, the overall environmental impact almost impossible to quantify.

This is exactly why LCA was created. Experts have developed tools and methods that enable us to put a ‘number’ on the environmental impact of our buildings,  considering everything from the extraction of the materials all the way through to deconstruction and disposal at the end of life. 

One of the main drivers in the industry for LCA at the moment is BREEAM. BREEAM is the world’s leading sustainability assessment method, established by the Building Research Establishment (BRE), and is used by the industry to demonstrate the sustainability credentials of their buildings.

The launch of the BREEAM UK New Construction 2018 scheme saw the introduction of completely new Mat 01 criteria - the criteria which encourage the use of low impact materials. The new criteria have moved away from assessing material impact using Green Guide ratings (the previous approach), and now use a ‘whole Life Cycle Assessment’ approach. (For background information on LCA and the recent changes in the Mat 01 criteria, this blog from the BRE may be helpful.) 

Despite the merits of the Mat 01 transformation, it is fair to say that in the first 18 months of its application the industry has shown itself reluctant to embrace the whole LCA approach. Reasons for this will vary, but in our experience here at Darren Evans Assessments, resistance has been caused by a combination of the following:

  1. Producing the LCA is more expensive than the previous methodology, and this increased cost is not accounted for in budgets.
  2. BREEAM requires the LCA to be carried out prior to planning submission; either it is not considered soon enough, or there’s insufficient budget at pre-planning stage to fund a full LCA.
  3. Challenging benchmarks (applicable for some building types) mean two credits out of six are extremely difficult to achieve.
  4. Clients don’t always understand the wider benefits of the LCA and are therefore not willing to invest in it.
  5. Human nature typically resists change, of course.

This narrative has been fed back to the BRE through various channels. While they might have assumed some pushback initially (see point 5, above!), over time it has become clear that there may be problems with the underlying issue. 

The BRE have responded to the industry feedback by running a series of workshops consulting on possible resolutions. And so I found myself, on a damp, autumnal Tuesday morning in Bristol, joining a group of other BREEAM Assessors to talk with the BRE about the Mat 01 criteria. The question of the day was whether to change the criteria or not. At the meeting, the BRE tabled four possible options for change:

  1.  Adjust the benchmarks;
  2. Adjust credit distribution for time related criteria (more credits available at Technical vs Concept design stage);
  3. Adjust credit distribution for simplified tool (enable more credits to be awarded – currently capped at two credits);
  4. Request adjustment to tool providers’ cost models (reduce upfront costs).

At the end of workshop we all voted on our preferences, and the results varied wildly, which I suspect was a reflection of the different types of projects and clients we all work with. It was clear that the BRE have a tough challenge ahead. 

Personally, I think there’s a broader issue here than the details of the criteria: the industry doesn’t yet understand the valueof the LCA. Disseminating this message can’t be done by the BRE alone – the responsibility sits with all sustainability professionals. But I do hope that implementing one or more of the above tweaks will help make the Mat 01 issue more appealing to the industry, and therefore support the message of how valuable the LCA is.

It seems obvious that there is no ‘one size fits all’ solution, so we’ll wait with anticipation to find out what the BRE’s final conclusions will be.  In the meantime, we must continue to work with what we have, helping our clients to understand the huge benefit that LCA can provide - not only to their projects, but to the environment.  

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