The Orms Sustainability Team have been undertaking an extended deep dive into the second edition of RICS Whole Life Carbon Assessment for the Built Environment in the run up to implementation on 1st July 2024, when it became an official standard. We have focused on understanding the changes, and potential impact on projects, as well as ensuring compliance.
The second edition represents a significant expansion in scope, ensuring like-for-like comparisons between buildings with detailed guidance on the calculation methodology. This includes default allowances for difficult to calculate modules, such as predictions of the building in operation (module B) and future deconstruction scenarios (module C). It is widely accepted that this will result in an increase in calculated carbon emissions, but the scale of the increase depends on a wide range of factors. Orms have always aimed for best practice, including allowing for significant contingency in design stage assessments, and has been implementing many of the changes manually in advance of software updates. We’ve compiled a list of the most significant changes/impacts below:
– Mandatory Scope has increased significantly – previously very limited to encourage data collection and understanding
– Uncertainty – requires 15% up to RIBA Stage 2, then 6-13% RIBA for Stage 4 onwards depending calculation based on top 10 contributing materials
– Decarbonisation of materials and energy to be reported separately, based on standardised Future Energy Scenarios
– MEP – take off assumptions provided where quantities aren’t available
– Default specifications, lifespans, and transport scenarios have all been expanded
– Retained elements need to be included so that their maintenance, repair and replacement are factored in
– New Module A0 for Pre-Construction – to be used for design team flights, office set-up for largest projects
– Demolition (A5.1) – allowance of 35kg CO2e/m2, previously excluded but reported separately
– Construction & Installation (A5.2) – allowance of 40kg CO2e/m2 GIA, previously very limited allowance based on EPDs (if available)
– Maintenance (B2) – allowance of 10kg CO2e/m2 GIA or 1% of Modules A1-A5, whichever is greater
– Repair (B3) – allowance of 25% of B2 of relevant items & 10% of A1–A3 for MEP
– Optional Module B8 for User Carbon to inform strategic decision-making on site location
– Energy Consumption (B6) – Part L calculations are no longer acceptable as they do not accurate represent actual energy usage. Previously only regulated energy was included. Should also include fuel allowances for annual generator testing.
– Future Deconstruction (C1) – 25-50% of Construction & Installation (10-20kg CO2/m2 GIA) depending on how much design for deconstruction has been implemented, previously 3.4kg CO2e/m2 GIA
To help explain the impact of the default assumptions, we’ve undertaken a series of worked examples. We’ve used the LETI rating system and taken the mid-point in the range. The adjusted figures are provided in absolute (kg CO2e/m2) and relative terms (% increase compared to baseline). We have included comparisons with varying levels of uncertainty factor, based on 0%, 6% and 15% to provide a useful range.
For Upfront Carbon, the Adjusted figures include allowances for Demolition (module A5.1) and Construction & Installation (module A5.2). Demolition will vary depending on the project but reasonable assumptions have been made for the purposes of the worked examples – i.e. 10% represents 100sqm of demolition for a total GIA of 1000sqm.
For Whole Life Embodied Carbon, the Adjusted figures include allowances for Upfront Carbon, plus Maintenance (module B2), Repair (module B3) and Future Deconstruction (module C1).
The worked examples only include adjustments which are explicitly quantified within the updated RICS methodology. As such, it does not consider increases in scope, default specifications, lifespans, and transport scenarios etc. However, it is likely to overestimate Repair (module B3) as this has been calculated as 25% of B2. Future Deconstruction is based on Good Practice at 30% of A5.2.
As one would expect, the lower the whole life carbon or smaller the original scope, the greater impact the updated RICS methodology will have.
back to insights
The Orms Sustainability Team have been undertaking an extended deep dive into the second edition of RICS Whole Life Carbon Assessment for the Built Environment in the run up to implementation on 1st July 2024, when it became an official standard. We have focused on understanding the changes, and potential impact on projects, as well as ensuring compliance.
The second edition represents a significant expansion in scope, ensuring like-for-like comparisons between buildings with detailed guidance on the calculation methodology. This includes default allowances for difficult to calculate modules, such as predictions of the building in operation (module B) and future deconstruction scenarios (module C). It is widely accepted that this will result in an increase in calculated carbon emissions, but the scale of the increase depends on a wide range of factors. Orms have always aimed for best practice, including allowing for significant contingency in design stage assessments, and has been implementing many of the changes manually in advance of software updates. We’ve compiled a list of the most significant changes/impacts below:
– Mandatory Scope has increased significantly – previously very limited to encourage data collection and understanding
– Uncertainty – requires 15% up to RIBA Stage 2, then 6-13% RIBA for Stage 4 onwards depending calculation based on top 10 contributing materials
– Decarbonisation of materials and energy to be reported separately, based on standardised Future Energy Scenarios
– MEP – take off assumptions provided where quantities aren’t available
– Default specifications, lifespans, and transport scenarios have all been expanded
– Retained elements need to be included so that their maintenance, repair and replacement are factored in
– New Module A0 for Pre-Construction – to be used for design team flights, office set-up for largest projects
– Demolition (A5.1) – allowance of 35kg CO2e/m2, previously excluded but reported separately
– Construction & Installation (A5.2) – allowance of 40kg CO2e/m2 GIA, previously very limited allowance based on EPDs (if available)
– Maintenance (B2) – allowance of 10kg CO2e/m2 GIA or 1% of Modules A1-A5, whichever is greater
– Repair (B3) – allowance of 25% of B2 of relevant items & 10% of A1–A3 for MEP
– Optional Module B8 for User Carbon to inform strategic decision-making on site location
– Energy Consumption (B6) – Part L calculations are no longer acceptable as they do not accurate represent actual energy usage. Previously only regulated energy was included. Should also include fuel allowances for annual generator testing.
– Future Deconstruction (C1) – 25-50% of Construction & Installation (10-20kg CO2/m2 GIA) depending on how much design for deconstruction has been implemented, previously 3.4kg CO2e/m2 GIA
To help explain the impact of the default assumptions, we’ve undertaken a series of worked examples. We’ve used the LETI rating system and taken the mid-point in the range. The adjusted figures are provided in absolute (kg CO2e/m2) and relative terms (% increase compared to baseline). We have included comparisons with varying levels of uncertainty factor, based on 0%, 6% and 15% to provide a useful range.
For Upfront Carbon, the Adjusted figures include allowances for Demolition (module A5.1) and Construction & Installation (module A5.2). Demolition will vary depending on the project but reasonable assumptions have been made for the purposes of the worked examples – i.e. 10% represents 100sqm of demolition for a total GIA of 1000sqm.
For Whole Life Embodied Carbon, the Adjusted figures include allowances for Upfront Carbon, plus Maintenance (module B2), Repair (module B3) and Future Deconstruction (module C1).
The worked examples only include adjustments which are explicitly quantified within the updated RICS methodology. As such, it does not consider increases in scope, default specifications, lifespans, and transport scenarios etc. However, it is likely to overestimate Repair (module B3) as this has been calculated as 25% of B2. Future Deconstruction is based on Good Practice at 30% of A5.2.
As one would expect, the lower the whole life carbon or smaller the original scope, the greater impact the updated RICS methodology will have.
back to insights