LCA submission stage – ‘Concept design’ and ‘Technical design’

As a building design passes through successive design stages, more and more aspects of the design become fixed.  The opportunity for building LCA to guide the design towards lower environmental impacts reduces as a consequence.  More credits are, therefore, available for a building LCA submission at ‘concept design’ stage, when there are more opportunities than at the later ‘technical design’ stage.

Concept design Mat 01 submissions

Two factors determine whether a Mat 01 concept design submission is valid: –

  • The local authority planning and building control status
  • The stage of the project

The table in KBCN1148 shows whether a Mat 01 concept design submission is valid according to the status of these two factors.

If a Mat 01 concept design submission has already been made but is now out of date (e.g. due to a change to the client’s brief or planning being refused) it becomes invalid. To achieve the concept design credits, an up-to-date resubmission must be made.

Technical design Mat 01 submissions

As stated in the manual, a technical design Mat 01 submission shall be submitted at the end of technical design.

If a technical deign submission has already been made but is now out of date (e.g. due to a change to the client’s brief) it becomes invalid. To achieve the technical design credits, an up-to-date re-submission must be made.

Where parts of a project are at different design stages

The whole project will often be at the same stage in the design process. However, it is possible for the three Mat 01 issue scope types ‘Superstructure’, ‘Substructure and hard landscaping’ and ‘Core Building Services’ to be at different stages. For each scope type, the most developed element comprising the scope type determines its stage. For example, if the roof element is at ‘concept design’ stage but the façade element is at ‘technical design’ stage, the ‘superstructure’ scope type is considered to be at the ‘technical design’ stage. In situations that are unclear, KBCN1156 should be used to confirm the design stage for the building and, if necessary, each scope type.

Which scope types can be included in a Mat 01 concept design stage submission depends on the stage each scope type has reached. For example, if the ‘Superstructure’ and ‘Core building services’ are at concept design but ‘Substructure and hard landscaping’ has already progressed to a later stage, only ‘Superstructure’ and ‘Core building services’ can be submitted at concept design. If ‘Superstructure’ has progressed to a later stage than ‘concept design’, none of the Mat 01 scope types can be submitted at ‘concept design’.


IMPORTANT: This KBCN shall be read in conjunction with KBCN 1148 ‘LCA submission stage – Applications for planning consent’

05//03/2020 Updated for clarity
10/10/2019 Clarifications added to paragraphs 2 and 4