Cold washing and when it is enough
Short answer: A cold wash at 20 degrees works on light dirt and saves most of the electricity. It does not work on sweat, grease and odour. Use it for clothes worn only briefly, and wash warmer when something smells.
What the cold cannot do
A cold wash at 20 degrees works on light dirt and saves most of the electricity. It does not work on sweat, grease and odour, and that is an important difference to know. If you choose cold for the wrong clothes, they look clean but are not properly washed, and you notice it later.
Enzymes and grease
The enzymes in the detergent are slow below 20 degrees, and grease is not dissolved. Enzymes are what break down stains in the detergent, and they need some warmth to work properly. In cold water less happens, and whatever is stuck in the fabric is just rinsed around a little.
Sweat and odour
That is why socks and sportswear often smell again shortly after a cold wash. Sweat and grease stay in the fibres, and the odour returns as soon as the clothes get warm or damp. If you recognise this, the answer is not more detergent but a higher temperature for that kind of clothing.
Where it works well
A cold wash works well for clothes worn for a single day indoors and for things that only need rinsing free of dust. There is not much sweat or grease to remove, so there is nothing the cold cannot handle. See bamboo clothing for women for clothes you wear in everyday life.
Coloured clothes and cold washing
For coloured clothes a cold wash is an advantage if you want to keep the colour as long as possible. The colour fades more slowly at a low temperature, so the garment looks new for longer. If you wash coloured clothes that have not been worn hard, you can safely choose 20 degrees and save electricity and colour.
How to do it better
Use a detergent made for low temperatures, and let the programme run longer instead of hotter. Time can partly replace heat, because the detergent has longer to work on the fabric. Choose a programme that is not extra short, and do not cram the drum full, so water and detergent can reach between the clothes.
Everyday clothes and cold washing
See bamboo t-shirts for men and bamboo underwear for men for pieces that can often get by with a cold wash when worn for only one day. Always check the care label first, and switch to 30 or 40 degrees if you notice odour or see stains that have not come out.
Looking after the machine
Cold washing makes the machine dirtier over time. Grease and detergent residue are not fully rinsed away at a low temperature and settle in the drum and the seal. Run a hot programme without clothes once a month to keep the machine clean. That stops odour from the machine settling into the next load.
When to turn it up
Turn it up to 30 or 40 degrees when the clothes were worn for exercise, are sweaty, smell or have stains. That also goes for socks and towels. A cold wash is a good tool, but only for clothes where there is not much to get out and where you want to save electricity and protect the colour.
Frequently asked questions
How much electricity do you save
Most of it. Heating the water is by far the biggest item in a wash, so a cold wash saves a large share of the electricity compared with a hot programme.
Does the machine get dirtier
Yes, over time. Run a hot programme without clothes once a month, so grease and detergent residue are rinsed out of the drum and the seal.
Is a cold wash better for the colours
Yes. The colour fades more slowly at a low temperature, so coloured clothes keep their colour longer when you wash cold. Remember, though, that cold does not work on sweat and odour.
You can find the full range at Bamboo-Clothing.com.
