The dataset assumes industry average end-of-life for all materials. For timber, this is the ‘Wood Landfill’ which also assumes worse case conditions of anaerobic decomposition where methane is produced. Hence the industry average default assumption of high end-of-life impacts for timber.
When arranged according to highest to lowest impact for end-of-life disposal/recovery method for timber, it is as follows:
– Combustion (no recovery)
– Wood Landfill (default)
– Combustion (electricity generation)
– Composting (commercial composting conditions)
– Combustion (heat recovery)
– No disposal (assumes no disposal at the end-of-life however should only be modelled as a scenario and not as a given)
As best practice, due to the unpredictability of real life conditions at the end-of-life of buildings/products, we should always assume the most likely worse case scenario and model our LCA studies using the default settings for that material. All other disposal/recovery methods should be modelled as a scenario for consideration.
Hope that answers your question!