When it comes to laundry, hot water is often praised for its ability to keep whites looking bright, eliminate bacteria from bedding and towels, and sanitise heavily soiled items.
Still, it’s not always the best choice for everything. Hot water is often more aggressive, shrinking certain fibres, fading bright colours and even setting in some stains.
‘Cold water is often the gentler choice, because it's less likely to cause dyes to bleed, fibres to shrink or elastic materials to break down,’ says Noah Pinsonnault, reviews analyst at the Good Housekeeping Institute Home Care & Cleaning Lab. ‘Advances in modern detergents also mean that many everyday soils can be effectively removed in cold water, so you don't have to sacrifice cleaning performance for most routine laundry.’
Before choosing the temperature setting for your next load, check this list for items that should always be washed in cold water, according to our expert.
Dark or bright colours
If you’ve ever done a load of whites and accidentally mixed in a sock or two, you know where this is heading. Washing vibrant clothing in hot water can cause the colour to bleed, and as a result, transfer on to other garments. For that reason, it’s always better to wash these pieces in cold water.
‘Dark or brightly coloured garments are good candidates because cold water helps minimise colour transfer and fading,’ says Noah.
Here's how to make white clothes bright again.
Delicates
Cold water is gentler on delicate fabrics like lace, silk and satin. When laundering these items, make sure to use a laundry mesh bag to avoid any snags or pulls, and check your machine’s settings for a delicate cycle.
Activewear
Activewear is often made with materials that can lose its elasticity when washed in hot water repeatedly. ‘Garments containing spandex or elastane benefit from cooler temperatures, which help preserve stretch and extend the life of the fabric,’ says Noah.
If you’re concerned about extra smelly gym clothes, you can pre-treat them or use an appropriate detergent for odour. Most detergents can handle extra soiled clothing, even on a cold water setting. There's also detergent designed explicitly for sportswear widely available.
Swimwear
Treat swimwear like your delicates to prevent colour fading or transfer and pilling. Just like activewear, swimwear is typically made of synthetic materials that can stretch out when washed in hot water over and over again.
Knits
Knitwear requires careful preservation and should always be washed in cold water (especially those made with delicate fibres such as wool or cashmere, which can lose their shape and softness otherwise). ‘Knitted jumpers are another good example, since warm or hot water can contribute to shrinking or distortion,’ says Noah.
Washing knits in cold water will keep their fibres intact. To be safe, turn these garments inside out before throwing them in the washing machine.
Stained items
While not every stain will come out after laundering, cold water is the safer starting point. Hot water can sometimes cause certain untreated stains to set whereas cold water works to lift stains.
Denim
There are a few key reasons denim should be washed in cold water. One, hot water can lead to colour fading and transfer, dulling out your favourite pair of dark blue jeans. And two, when exposed to heat, denim fibres might shrink over time.
Jeans or denim jackets are an everyday staple for most people. These comfort items you reach for time and time again are generally best preserved with cold water since it’s gentler on most fabrics.
