Full Lifetime Analysis (Cradle to Grave)

Embodied CO2 is an increasing fraction of a building’s carbon footprint as the electricity grid decarbonises. CO2 released from electricity use is reducing and other fuels will follow as we head towards a zero carbon future.

PHribbon now calculates a full Cradle to Grave LCA, covering stages A-C and D suitable for initial estimates for the RIBA 2030 Challenge. The full LCA version of the embodied CO2 calculation release date has been delayed to Mon 3rd Feb 2020 to allow for further testing.

  • typical house calculation a few minutes +look up special materials + checking
  • uses standard RICS methodology including 60 year nominal life
  • quantities taken from the PHPP where available
  • uses data from 200 material entries from EPDs and a further 100 from summaries of EPDs
  • matches materials automatically, though user needs to confirm each
  • simple front screen allows you to skip items or add to existing calculations
  • fully referenced with links to the EPD and the source of the density and product life
  • user can adjust the density of some products, standard densities are offered
  • stored carbon for timber based products is included, easy to turn off for all, or for non FSC/PEFC
  • easy choice of units for the y axis of graphs

Lifecycle Assessments are divided into:
Stage A, A1-A3 Manufacture including A4 Transport to site and A5 Construction
Stage B, Use of the building including B4 Replacement
Stage C, Demolition and Disposal of the building
Stage D, Reuse, Recycling potential (outside the usual scope of the calculation)

An example result is below. It shows a graph from the new tab of PHPP that is created with an overall result of the calculation on the left and more detail on the right. Operational emissions for heating, electricity and water are not included. The left hand bar is for a timber I-beam and cellulose wall construction, the right hand bar for a cavity wall construction of similar U-value with brick as the outer leaf.

Existing version (Cradle to Practical Completion)

Youtube 5 min introduction
New Embodied CO2 part 1 – Basic use (13 min)

  • 200 material entries from EPDs and a further 100 from summaries of EPDs
  • matches materials automatically, though user needs to confirm each
  • includes transport, using RICS methodology
  • automatically also calculates the stored carbon figure for timber based products
  • graphs the result with an error bar, max min limits

This button calculates the CO2 for the manufacture the materials in a new building or retrofit. The new version was presented at the Passivhaus Trust Masterclass.

We do the calculation for you or you might want to buy the tool and do the calculation yourself.

Results for Steep Wedge house were recently published in Passivhaus+ magazine (issue 31 p49).

We also got the same result (within the error margins) as Mark Siddall ‘s own 2-3 day calculation. The Embodied tool was in development when Mark did his calculation and he was interested in a to see what it would produce, before revealing his own results. When it gave the same answer in about half an hour he said “I’ll definitely be using it next time”.

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