Last edited 14 May 2019

BREEAM Life cycle impacts


[edit] Aim and benefits

The aim of the Mat 01 Life cycle issue is to understand, consider and reduce the environmental impacts of projects from the construction materials used.

This used to be done with reference to the Green Guide but the data is over 10 years old and is not aligned to EN standards. The Building LCA replaces the Green Guide approach with credits now awarded for:

  • Comparison against the BREEAM LCA benchmark.
  • The number of design options appraised.

EPDs have long been used to help assess the environmental impacts of individual building products. In BREEAM 2018, this analysis takes the process one step further and is used to assess the environmental impact of the whole building. As well as construction products themselves, the analysis includes impacts from transporting them to and from site, their maintenance and what happens at the end of the building's life in terms of demolition and waste processing.

When taken in the early phase of the design, this analysis can help identify material quantity savings or material type changes, or when done later on, it can help identify the best performing materials from an environmental point of view.

[edit] Value for Clients

Life cycle analysis (LCA) helps familiarise the client (and design teams) with the importance of embodied carbon, and how to reduce carbon emissions through the specification of low-carbon alternatives, both in material choice, construction methods, and in use/maintenance impact.

Where this is done early-on in the process, it helps the client choose the best building components at no extra cost. Good value credits can be had to gain a high BREEAM score, since relatively low input is required - the process is no more onerous than normal if LCA is adopted early on and integrated into the design process.

[edit] When to consider

Most BREEAM schemes require this credit to be tackled in the design phase. The exception is the BREEAM UK NC 2018, which requires this credit to be addressed before applying for planning permission.

BREEAM operate a rigourous process for the submission of results (through date stamped Excel tools):

Therefore it is important to communicate the importance of Mat01 in BREEAM 2018 to the design team at the earliest opportunity. Design teams are usually considering different options in terms of cost and aesthetics so this is a goood time to bring in LCA as well. The biggest opportunity to minimise the embodied impacts is early on in the design process.

[edit] Step-by-step guidance

Most design teams will require the services of an external consultant to carry out the full LCA analysis.

The most time consuming element of the analysis is the collation of the data. It is very unlikely that the supporting evidence will come from just one source. An early meeting can help identify the likely sources of data. Where available, a cost plan or bill of quantities prepared by the surveyor is a very good starting point, supplemented by drawings and sketches. Some LCA software supports integration with common design tools and the analysis can be supported with data (via plugins) from BIM models, energy modelling tools as IES Virtual Environment as well as DesignBuilder, and Revit.

The design team should review all the quantities once the data has been collated, and provide any clarification required.

Tackling this credit requires following a number of steps which vary by the applicable BREEAM scheme. Some software tools include scheme-specific workflows to support this credit. For example, One Click LCA includes specific workflows for BREEAM UK NC 2018 (benchmarks and optioneering) as well as BREEAM International, BREEAM SE, BREEAM NOR, BREEAM ES and BREEAM DE (for the new construction and renovation versions). Energy modelling tools such as IES Virtual Environment and DesignBuilder, and by automating the analysis using Revit models.

[edit] Questions to ask while seeking compliance

Design team experience is key to maximising credits in this issue. It is likely in most instances that an external specialist consultant, using a compliant software tool, will need to be engaged. BRE pre-approves the software that can be used for this credit. It cannot be documented without an approved software solution.

Compliant software tools are documented by BRE in the so-called Mat 01 calculator which is available in the BRE Extranet. However, for BREEAM UK schemes the approved software are listed here:

One part of the BREEAM UK compliance requires using IMPACT-compliant software. The IMPACT-compliant software can be found here:

For BREEAM NOR, the Mat 01 credit includes both use of an LCA software, as well as greenhouse gas accounting using the Norwegian national standard NS 3720.

For BREEAM NL,the Dutch regulatory method is applied and software complying with that can be found here:

In terms of software instruments, One Click LCA is approved for every BREEAM scheme as an LCA software, and allows targeting every credit for the Mat 01 LCA as well as associated EPD credit(s). It has several specific modules, including specific tools for IMPACT-compliant (BREEAM UK), Non-IMPACT compliant tool (BREEAM UK), BREEAM International/NOR/ES/SE/DE tool, and specific tool for BREEAM NL and a specific tool for BREEAM NOR’s national greenhouse gas accounting method.

[edit] Tools and resources

Design teams can integrate building LCA into their design process using a tool recognised by BREEAM. The current options are:

The highest rated LCA tool for BREEAM is One Click LCA, which has received a Mat 01 100% rating and once the appropriate data has been gathered, allows users to calculate Life Cycle Impacts credits quickly and easily.

[edit] Tips and best practice

Most design teams will not have the specialist knowledge required to carry out this complex analysis and will probably engage the services of an external consultant to carry out the full LCA analysis. Make sure that the consultant is engaged early enough to guide the collation of meaningful data, drive the option appraisals and present the results for consideration prior to the concusion of RIBA stage 2 (and in the UK before submission for planning approval).

Addressing the credit early on, and using automation to speed up this credit analysis are very important productivity factors, as is the consistency of datasets used.

BREEAM require the appraisal of 2-4 Superstructure (Structural material, Facade systems, grid size etc) options at Stage 2. Focus on the large changes that might be straightforward to incorporate in the early stages but would be more difficult later during the design process.

BREEAM require the appriasal of at least 6 Substructure (Foundation types, Basement walls) and landscape options (Hard surface materials, Loading and vehicle access strategy) with a minimum of 2 substructure options and a minimum of 2 landscape options. In practice, substructure options may well be limited by site and ground conditions, so it makes sense to focus more on different landscape options.

The results should be communicated to the design team and the information used to inform the design.

Remember - The option with the lowest impacts does not need to be selected, but justification is required for the choice.

[edit] Typical evidence

The evidence is generated by the LCA software. It takes the form of Excel spreadsheets, whose content varies by the BREEAM scheme.

Documentation in the form of a report should also be provided. The report should provide a summary of the option appraisals, which is updated regularly to include outcomes, through the inclusion of minutes, option descriptions and the associated results.

[edit] Applicable Schemes

The guidelines collated in this ISD aim to support sustainable best practice in the topic described. This issue may apply in multiple BREEAM schemes covering different stages in the life of a building, different building types and different year versions. Some content may be generic but scheme nuances should also be taken into account. Refer to the comments below and related articles to this one to understand these nuances. See this document for further guidelines.

BRE Global does not endorse any of the content posted and use of the content will not guarantee the meeting of certification criteria.

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