Green Breakthrough: Save Energy by Washing Diapers in Cold Water

I’d always heard that diapers needed to be washed in the hottest water possible.  After two years of washing diapers in hot water, a post on Treehugging Family made me think about whether I could wash diapers in cold.  Peggy writes about saving 72 pounds of carbon dioxide in one month just by washing four out of five loads in cold water.  Keep that up for an entire year and you’ll save $60-100 on your energy bill. 

front-loading washing machine for cloth diapersBut doesn’t washing in hot water kill germs and bacteria?  Everything I read said no–unless your washer has a built-in heater, the hot water in your machine does not get hot enough to kill anything.  Most water heaters are set to 120 degrees.  You’d need a temperature of 160 to kill anything and 212 to actually sanitize your laundry.  Jennifer (Peggy’s co-blogger on Treehugging Family) pointed out that the dryer does get hot enough to kill bacteria.

Armed with all this information, I figured it was worth a try.  I loaded the diapers in the machine and set the knob to “cold.”  At the last minute, I almost turned the knob back to hot.  After years of believing the hot water I was using was beneficial–no, necessary–to the cloth diapering process, it was hard to make the change, even for investigative purposes.  Then, in one of the most daring moves of my cloth-diapering career, I pressed the start button and let the cold water gush into the machine.

Now that you are all on the edges of your seats, I’ll break this amazing news: the diapers came out of the dryer white, clean, and fresh-smelling.  Now, if anyone has some scientific evidence in favor of the hot-wash, please post a comment.  Until I hear advice to the contrary, I am going to wash diapers in cold water.  I just wish I’d had the gumption to take the plunge years ago!


  1. That’s right, Jen. The hot water can help wash diapers better, but they aren’t actually sanitizing. The idea is to try cold and see if your diapers come out just as clean. If not, go back to hot water or longer cycles or whatever it takes–but try the lowest impact method first.

    Do most cloth diapers have PUL? Mine were 100% cotton.

  2. HeatherA says:

    I love in the USA. I have a washer that only has a hot/cold cycle for the hottest. It doesn’t even get as hot as I would bathe in. Our DD has had plenty of urine burns to prove it doesn’t work. The hot water is needed to get the soap out> It’s the soap and the agitation that neutralizes the acid and breaks up the filth making it come out of the diapers. Especially when stripping diapers because you use stronger soap, the hot water is essential. Any stink = acid and germs. Our fore-mothers boiled their diapers. For those of you who live where hot water is not available you will have to boil them (but not with PUL in them). For those with cheap washers like mine you can either boil enough water to fill the tub of your washer or take your diapers to a laundry mat. I’m all for natural but I’m not for spreading untruth. You need to make your diaper water hot to get the soap out. You are right with the facts about sanitizing though.

  3. Hi girls! I’m 17 so that means I do all the dishes, haha. We have a dish washer and the dishes come out filmy and crusty and gross…I even find food bits every now and then. So, we have been hand washing them, and I use cold water and my sister uses hot. The only difference I see is that her hands are red and mine aren’t! Also, sometimes her’s break from the quick heat changes. But that’s only with the glasses, silverware and other things that look about the same going in as coming out. I do the hot and super soapy for gross stuff. Also, as a tidbit of tips, I wash the glasses and forks first, rinse them above the water already there, and then do plates, then rinse above, then do the big stuff. It’s a lot of planning before, but the water level doesn’t have to be too high for glasses and it does for pots, so it makes sense to me. I don’t know, but I’ve never gotten sick from a dirty plate, or from eating anything at my house really…

    Oh, and for the grandmother thing, she would usually wash them by hand in a bucket outside in the summer and in by the fire in the winter then line dry it…I don’t know how well that worked in the winter… The line is still outside, it’s a bird stand now though, she has Alzheimer’s disease so now I’M the one changing the diapers! Haha. I also go out and help my pappaw clean once a week and wash the dishes the same. Trust me, it’s better me washing them in cold water than expecting him to clean it well…

  4. Oh, and for the soap thing you can google “how does soap work” and you can get really detailed answers but basically oil (from hands, dishes, whatever) is on substances, oil attracts dirt. If you put water on oil they usually separate, soap, however, makes it so that the oil can go up into the mixture and then the grubby stuff becomes soluble, in which you rinse off. In a healthy home there is no need really for things to be bacteria free, this was invented for hospitals really. When you kill off bacteria on a surface you kill the good stuff too, you’ve heard this before, but when all the bacteria is gone the bad bacteria can multiply quickly with all the good bacteria gone. It’s like there’s 1 bad bacteria but 99 good bacteria, controlling the bad bacteria and starving it off. You kill all the bacteria and 1 bad bacteria and 1 good bacteria fall back on from the air (unless you sterilize your whole home it’s useless anyway) the bad bacteria can multiply ultra quick, then it’s more like 50 bad bacteria and 50 good bacteria. This is all summarized stuff. I know I’m young but a study a lot.

  5. In response to an old comment above, household bleach (like Clorox) is NOT an enviromental toxin, over 90% of it breaks down naturally and the rest is destroyed during sewage treatment. It is the industrial uses that bleach produces dioxin and other pollutants (an example would be bleaching of wood pulp for use in paper products).

  6. I saw it asked above but never saw anyone mention that diapers are not 100% cotton anymore so cleaning them can call for different measures. In the old days they bleached them. S is correct, bleach is not an environmental toxin and keep studying because the good vs bad bacteria is not a blanket thing. Bacteria is not good or bad per se usually there is an overgrowth of something that occurs naturally in the body that causes disease but we are discussing introducing something to the body that may contain microorganisms that can be harmful in the wrong place. Example; e. coli is fine and necessary in the intestine (o make vitamin K and B complex vitamins) but it is the leading cause of urinary tract infections because it gets into the “wrong” place where our bodies can not handle it. It is not the same concept with the air and dishes. I found this because my microfiber says not to bleach it and to wash in hot. I do not see mention of type of fibers it is ok to wash in cold. I have bamboo now that say to wash warm or cold. Any thoughts on the microfiber issue? I can not dry outside because of condo regulations. :(

  7. i hardly ever wash my nappies on more then 100F, if i get stains i use few drops of Fairy liquid soap mixed in with big glass of water spray it on the stain leave for 30 mins and wash out as normal in the washing machine and good extra rinse (2-3 times) to get all the soap out i use the sun when i get it which aint too often except summer, if the nappies start to smell i use either baking soda or vinegar in the washing machine,
    Layla it should be ok to wash your microfiber in cold as well, i do it with mine, i put everything in the dryer as well except for the PUL fabrics ie pockets/covers etc

  8. You can wash in cold water, and add bicarb to the wash. This will brighten up nappies. If you do use bicarb in the wash cycle, make sure you put vinegar in the rinse cycle to restore the pH of the cloth diapers. Bicarb (Baking soda) works with detergents to whiten and brighten laundry. For an even more environmentally friendly wash, use soapnuts instead of soap.
    line dry in the sun.

  9. Gramma Janice says:

    I have washed ALL clothes in cold water for many years, and there have been no problems. They do not fade, seem to shrink less, and wear longer. In the summer I hang them outside and sunlight helps kill germs as our grandmothers probably knew. If adding borax or some other booster, I turn the warm water on long enough to dissolve it then add soap and clothes when it has filled.

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