Why washing at 40°C is not a great idea

When Gab and I moved in together I was 24 and I had half a clue on how to do things around the house.

My mum – the microwave queen, remember? – had always taken care of all the washing and cleaning, so I had no idea but I was too proud to ask for advice at the same time.

That, of course, resulted in lots of ‘re-sized’ clothes. However, my forte was changing colours because I wasn’t the best at separating coloured garments from whites. I had a lot of pink tops at some stage…

Gab has been reminding me for the last 10+ years of that time when his favourite pair of very expensive suit pants turned into a 8 year old size.

Luckily for everyone, my washing skills have improved dramatically since 2012. Not only that, the great thing about newer washers is that they tell you exactly which program is recommended based on what it is that you are washing, i.e. bedding, delicates, baby, etc.

What I noticed, though, is that I have been using the same two-three programs which may not necessarily be the most cost-efficient in times like this, where the electricity bill seems to have doubled if not tripled. 

Especially, there seems to be a misconception that 40°C is a universal temperature, that works for most things, while instead it may not be ideal as it can break the bank over time.

So, why is that 40°C such a bad number? Let me explain below.

Most detergents produced these days work wonders from a temperature as low as 20°C and some even work with cold water. In most cases, increasing the temperature to 40°C won’t make any difference to the end result and, most likely, it will just lead to a more expensive electricity bill.

Obviously, there might be some exceptions where you might need to go as high as 40-60°C, for best results, to wash cotton bedding, towels or anything stained badly.

Otherwise, keeping your water temperature down can be your best option for the environment and your wallet alike. On average, the consumption can drop from 0.7 kWh to 0.4 kWh when you reduce the temperature from 40°C to 30°C!

Another good reason for making the switch to a low temperature is that you can be less careful when separating your garments, with a few exceptions, of course.

Finally, washing clothes at 60°C or more may result in them shrinking and, if you are dealing with delicates like wool, you might need to drop the temperature even further. Always keep an eye at the labels!

Bonus: Sydney’s daycare clothes usually come home really stained with food, any sort of colour from their activities and from crawling on the ground. With the real nasty stains I usually spray them with vanish or rub them with Marseille laundry soap and leave them in water for a couple of days, while I have enough for a full load. I used to wash them at 60°C, however I’ve noticed that I can achieve exactly the same result at 30°C.’

I hope you find this useful 🙂