Building LCA – Scope when a BREEAM Assessment covers only part of the new building design

To give reliable results, building LCA 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 building LCA the designer may choose a design option that optimises environmental impacts for the limited part analysed, but will be unaware of potential detrimental effects to the overall environmental impact of the building.

In addition, if a building LCA 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, the building LCA scope should normally include the whole building design (as defined in Mat 01, ‘Scope of assessment’) even if the area covered by the BREEAM assessment scope is only part of the building.

However, where in the opinion of the BREEAM Assessor this is not reasonable, it is acceptable for the building LCA scope to match the BREEAM assessment scope. Examples where this may be the case include newly-constructed, mixed-use buildings (where the different use zones are assessed under different schemes or some are not being assessed at all) and part new-build part refurbishment projects.

Where this is the case:-

  • Comparison with the BREEAM benchmark cannot be done, only options appraisal.
  • Only include construction elements/components that are both:

Within or forming the boundary of the BREEAM assessment scope.
Predominantly the responsibility of the project team undertaking the building LCA work.

Note: Based on the above conditions, if no construction elements/components are included, or what is included is too limited to have significantly different options to appraise, then credits cannot be awarded.

  • In the BREEAM Mat 01/02 Results Submission Tool: 

Select ‘Other’ for the ‘BREEAM assessment building use type’ (note: ‘mixed-use’ should only be entered for mixed-use buildings where the whole building is included in the building LCA scope).
For ‘Functional quantity…’, enter the value corresponding to the scope included in the building LCA.
Include the following text in cell C10 of the ‘DifferencesID2,3,4’ sheet: “The scope of this building LCA work matches the BREEAM assessment scope, which covers only part of a building being newly constructed/refurbished. Of the areas being newly constructed/refurbished, the building use type(s) of the areas included in the building LCA scope are [insert use type(s)] and the building use type(s) of the areas excluded are [insert use type(s)]. The Functional quantity of the areas excluded are [insert value]”.

01.12.2020 Clarification to previous update added.
27.11.2020 Exceptions paragraph added.
06.12.2019 Scope of KBCN clarified.