What the study found: the number of times a garment is the most influential factor in determining impacts.  Clothing that is worn  more often and is kept for longer reduces the overall impact on the environment and thus is more sustainable.

It’s how you use it

Many brands struggle to know which materials are best for the environment, as there are pros and cons to all. Often tools look only at comparing fibres on the basis of production and processing. This leaves out what actually happens when the clothes are being used.

“Our work increasingly shows that comparing fibre types is not relevant,” says the lead author of the LCA, Dr Stephen Wiedemann. “We won’t fully understand the true impact of an article of clothing unless we account for why the garment exists and how it is used.”

The first of its kind

Previously, little research looked at the full lifetime of wool garments. The majority of wool LCA studies focused on a single segment of the supply chain.

Seeking to address the knowledge gap, Australian Wool Innovation initiated this LCA research. AWI is a not-for-profit company that invests in R&D for the Australian wool. The Australian Government provides matching funding.

“This is one of the few published studies of a full supply chain for a garment, with detailed data behind it,” says Dr Wiedemann. “Of the major fibres, only cotton has also published such substantiated LCA work. None of the synthetics or cellulosic fibres have.”

Where wool can help improve

Washing and drying has a significant effect on sustainability. Wool naturally inhibits odour and can be aired, reducing the need to wash. Similarly, when washed, wool garments can be line-dried. This saves the energy needs to tumble dry.

The wool industry will build on the LCA research by looking further into wool garment care and how to communicate best care practices to wool customers.

Environmental impacts associated with the production, use, and end-of-life of a woollen garment,  by Wiedemann, Biggs  et al, was published 25 May 2020 in The International Journal of Life Cycle Assessment.