If you spend any time at all on Facebook cloth nappy forums (and for your own sanity I suggest that you don’t), you will be aware that there is a lot of debate out there on how to wash your nappies. Grandparents, remembering terry squares and twin tubs often recommend washing at 90°, the uber-eco conscious recommend 30° and a whole host of other temperatures in between.
Go Real, the reusable nappy campaigning body recommend washing at 60° (there full washing instructions are here http://www.goreal.org.uk/real-nappy-washing-guidelines), as do the UK Cloth Nappy Library Network. The reasons for washing at 60° rather than a lower temperature is that research shows that a good dose of detergent, combined with washing at 60° will kill or remove most bacteria. 30°-40°is very close to body temperature and can encourage bacteria to breed.
Advise to wash at 90° is particularly worrying. The Environment Agency report of 2008 specifically mentioned that washing at 90° was one of the reasons why using cloth can end up being as bad for the environment, whereas washing at 60° or lower reduces the carbon footprint of your nappies (washing a full load and line drying when possible also helps with this – see my blog on whether cloth nappies are actually greener). A very hot wash can also cause your nappies to delaminate (when the waterproof layer comes away from the fabric). I actually had this happen when my husband put the nappies on at the wrong temperature by accident. Finally, from a financial point of view, washing at 90° will invalidate your warranty with the manufacturer. Most manufacturers recommend washing at 60° (and some even as low as 40°) so always check the wash care label on your nappies when washing them!
If you are worried about staining, a cold rinse before washing can help prevent stains from setting.
So remember, wash at 60° or lower to protect your nappies, protect the environment and protect your warranty.