I’m doing a case study LCA of a building renovation project. In the A1 version of the Levels norm there was an option to include generated construction waste which can not be found in the new version. Why is that?
There are a lot of different demolition segments within the project, such as demolition of floor tiles, dismantling of flat roof layers, removing screed layers or removing the plaster layer. I have been modeling the renovation project using a University license. Under the category deconstruction/demolition scenario C1 there are only a few scenarios and they are assuming an average value of a whole building demolition.
How could I, most realistically, model the demolition and removal segments of the project?
When we initially created the Level(s) +A2 tool, after the EN 15804+A2 standard became mandatory, there was not much data available in the required +A2 format. This was also true for waste data, which was unavailable at the time. Today, far more data is available that complies with the +A2 standard, including for waste.
This means the waste category will be added back into the Level(s) +A2 tool in a future update. I can’t give you an exact date, but it will happen within the coming months.
Calculating Demolition Emissions
The demolition of a building typically occurs in the C1 life cycle stage and should be allocated to that previous building’s life cycle, not the new project.
For your purpose, you could calculate demolition emissions based on the fuel used by heavy machinery, which is a common measurement method. This would however attribute the emissions to A5, which is technically not correct.
The impact of carefully removing segments is more difficult to calculate realistically, as it depends on how their connections were made during the initial installation. You might also want to look into the scenarios for pre-construction demolition used in the UK, which focus on Global Warming Potential (GWP), they have fixed values and are assigned to A0, which in the UK is pre-construction demolition.
The C1 scenarios that exist are indeed for the entire building and would target the ‘new’ (post-renovation) demolition.