81-103 King’s Road is a proposed 17,000m² mixed-use development located in the Royal Borough of Kensington and Chelsea, London. KJ Tait Engineers calculated the Whole Life-Cycle Carbon (WLC) of the proposed building that conforms with the London Plan 2021 requirements for referable buildings.

In line with BS EN 15978, the following modules must be assessed:

• Module A – Product/Construction
• Module B – In Use
• Module C – End of Life
• Module D – Benefits beyond the system boundary

Using OneClick LCA software, a baseline model was created from the RIBA Stage 2 Cost Plan and material benchmark data from RICS Whole Life Carbon Assessment for the Built Environment. Options to reduce the life-cycle carbon emissions were assessed with the Design Team and the associated carbon savings were calculated.

Measures Implemented

The following measures were agreed by the Design Team:

• Concrete with at least 60% Ground Granulated Blast-furnace Slag replacement – expected saving 75kgCO2e
• 100% recycled reinforcement – expected saving 8kgCO2e
• 40% recycled structural steel – expected saving 16kgCO2e
• CLT floor slabs – expected saving 12kgCO2e

Together with the above measures, the upper floors will benefit from mixed-mode ventilation. This is expected to save 134kgCO2e/m2 in use, using today’s carbon factor.

Result

The resultant scheme is one that betters the Greater London Authorities’ aspirational benchmark for offices for modules A, B and C.