New Construction / UK / 2018 / 06 Materials /

Mat 03 - Responsible sourcing of materials

Information correct as of 27thJanuary 2022. Please see for the latest compliance information.

Design stage requirements where specific product details are unknown - KBCN1483

The Mat 03 tool must be completed in accordance with the Methodology, providing all available details and submitted as evidence. Where products or materials are subject to a performance specification and a specific manufacturer and certificate reference cannot be provided, the missing details should be completed as 'tbc'. This ensures that a strategy for compliance can be demonstrated, even where some specific details are unavailable.

FSC Controlled Wood - KBCN00054

FSC Controlled Wood is a system developed to ensure that the non-certified portion in products labelled as Mixed Sources do not come from unwanted sources. It is not an FSC certification on its own and products classed as FSC Controlled Wood do not meet the BREEAM definition of responsibly sourced.  

Legally harvested and traded/Legal and sustainable timber – Reclaimed/recycled timber - KBCN0654

Timber should, wherever possible, be sourced in accordance with the UK Government’s Timber Procurement Policy. However, if for reclaimed timber the original procurement details are unobtainable, robust evidence to demonstrate it has been reclaimed can be acceptable. The government UK Government Timber Procurement Policy Timber Procurement Advice Note (6th edition) states: As an alternative to demanding timber and wood-derived products from a Legal and Sustainable source, Contracting Authorities can demand ‘recycled timber’. Documentary evidence and independent verification will also apply to recycled timber and recycled wood-derived products but will focus on the use to which the timber was previously put rather than the forest source. And defines ‘recycled timber’ as: “…recovered wood that prior to being supplied to the Contracting Authority had an end use as a standalone object or as part of a structure and which has completed its lifecycle and would otherwise be disposed of as waste. The term ‘recycled’ is used to cover the following categories: pre-consumer recycled wood and wood fibre or industrial by products but excluding sawmill co-products (sawmill co-products are deemed to fall within the category of virgin timber), post-consumer recycled wood and wood fibre, and drift wood. It also covers reclaimed timber which was abandoned or confiscated at least ten years previously.” As per the above policy, BREEAM requires “Documentary evidence and independent verification” that all reclaimed/recycled timber products meet the definition of ‘recycled timber’ given above.
01/06/2020: Amended to clarify and extended applicability to Mat 03

On site fabrication - KBCN1292

Where concrete (or another construction product) is produced on site, there is no requirement to provide responsible sourcing certification for the end product. As in this case fabrication on site is effectively part of the onsite building process, the certification of the individual products (e.g. aggregates, cement), as delivered to site, shall be used in the assessment instead.

Responsible Sourcing – Scope when a BREEAM assessment covers only part of the new building - KBCN1217

To give reliable results, the assessment of responsible sourcing must capture the interactions that occur across an entire design (the system). A design decision in one part of the design will, in many cases, cause knock-on effects to other parts of the design. If only part of a building being designed is included in the assessment the designer may choose a design option that optimises responsible sourcing performance for the limited part analysed, but will be unaware of potential detrimental effects to the overall responsible sourcing performance of the building. In addition, if a responsible sourcing assessment only includes the construction products that form the BREEAM assessment area, inconsistencies arise with regards to construction products that serve all areas of the building in common. For example, an assessment on a central floor that excludes the roof, compared with an assessment on the (otherwise identical) top floor that does include the roof. This approach would be unfair. Therefore, notwithstanding the exception below for internal finishes, the responsible sourcing scope must include the whole building design (as defined in Mat 03, 'Scope of assessment') even if the area covered by BREEAM assessment is only part of the design. The exception to this is any construction products classified as '3. Internal finishes'. Internal finishes are specific to each part of the building with little or no functional relationship with other parts. Therefore, the scope of the assessment of internal finishes shall be limited to the assessed area only.

Responsible Sourcing – Evidence requirements for two (or more) BREEAM assessments on different parts of the same new building - KBCN1218

As the responsible sourcing assessment work must cover the whole new building design (see KBCN1217 'Measuring Responsible Sourcing - Scope when a BREEAM Assessment covers only part of the new building design'), it is equally applicable to all BREEAM assessments being carried out on the building, with the exception of internal finishes. If the assessment scope does not include any construction products classified as '3. Internal finishes', the same responsible sourcing assessment evidence may be submitted for each BREEAM assessment. If the assessment scope does include construction products classified as '3. Internal finishes', then the responsible sourcing assessment evidence submitted must be unique to each BREEAM assessment.

Responsibly sourced timber – government licence - KBCN1033

A government licence, e.g. a UK Forestry Commission felling licence certificate, can be used as evidence of legally sourced timber. It does not meet the definition of a third party timber certification scheme so cannot demonstrate compliance with the responsible sourcing requirements of this Issue.

RSCS summary score level for BES 6001 products - KBCN0955

For products certified under BES 6001, the rating score (between 5 and 7) can be found in the Green Book Live. This is the rating that needs to be entered in the Mat 03 calculator. The RSCS score that is entered into the Mat 03 calculator comes from the relevant table in Guidance Note 18. However, for BES 6001, the score is per certificate because 6001 works at different levels of rigour.  Once you have found the product, by searching on the page below, click 'More..' on the right-hand side to reveal further details, including the BREEAM score level. GreenBookLive Responsible Sourcing

Setting of Responsible Sourcing Certification Scores (RSCS) - KBCN00017

Mat 03 credits require the majority of the materials used to be sourced with a high RSCS score. While maximum points (10) are available for reused materials the points available for RSCS's are typically less than 10. The available points are representative of the relative merits of each source while also providing some incentive for each scheme to improve and gain higher scores in the future. The latest points scores for each RSCS route are available in the latest version of GN18.  
Information correct as of 27thJanuary 2022. Please see for the latest compliance information.