Finally I’ve got round to starting to learn & use PHRibbon by Tim Martel (a plug-in for PHPP that calculates Embodied carbon in a building).
Why? Well, we really need to start thinking about materials more.
The equation is really straightforward:
Total embodied carbon of your building = Quantity of materials x Carbon Intensity of the materials
If we can either reduce the quantity of materials or the Carbon Intensity of the materials or do both – we are lowering the amount of CO2 being pushed into the atmosphere. If we can do this we can maybe have some chance against the climate emergency.
So how can you find out the carbon intensity of a material? Ask the supplier for the Environmental Product Declaration (EPD).
The bar chart below from John Butler gives the embodied KgCO2/m2 of insulation with same U value for a variety of different materials. The conclusion is that we really need to move away from petro-chemical based products towards more natural solutions:
Image from John Butler – https://www.sustainablebuildconsultancy.com/
The software we’re now starting to use that plug-in to PHPP (The Passive House software) is PHRibbon from Tim Martel. It effectively takes the areas of the building from PHPP and the you allocate the building and construction materials; including types of windows etc… and the software calculates the Embodied CO2 – see the example below on a PHPP calculated house we recently completed. What’s interesting is that you can use this tool as part of the design process; investigate the difference in CO2 between PIR, EPS & wood fibre for example…:
More on this to follow… hopefully big news to come on the work that we will be undertaking going into 2021 in a Covid-19 world!