How to Wash Underwear Properly
How to wash underwear so the elastic survives: the right temperature, why fabric softener wrecks cotton and synthetics differently, and when to go hot.
An Apology to Every Pair of Briefs I Have Wronged
An apology to seven garments I destroyed through carelessness, and the laundry lesson buried in each. A care guide in the shape of a confession.
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I keep a small bag of retired underwear at the bottom of a wardrobe, which I understand is not normal, and which I have never satisfactorily explained to anyone who has found it.
Some are simply worn out, and those I have no argument with. Cotton gives up eventually, elastic gives up eventually, and a garment washed two hundred times that has finally stopped snapping back has done its work honourably and owes me nothing.
The ones that bother me are the ones I killed.
Every garment in that bag with life left in it is there because of a decision I made, at speed, while thinking about something else. Since none of them were consulted and none of them can respond, I would like to put a few things on the record.
To the pair I put in the tumble dryer, repeatedly, for eleven years
You were a good brief. Combed cotton, a contoured front, a woven waistband with a name on it, and I had bought you deliberately rather than by accident, which is more than I can say for most of your colleagues.
I cooked you.
Not once, which would be forgivable. Every single wash, for over a decade, in a machine on the hottest setting because that was the setting it was already on. I want to be clear that I knew. I had read the label. The label had a small square with a circle in it and a line through the circle, and I looked at that symbol perhaps two thousand times and thought, in effect, yes but I need them for Thursday.
What I was actually doing was this. Elastane and rubber elastic lose their recovery when heated, and a tumble dryer applies more heat in forty minutes than a year of wearing ever will. The fabric survives it. The waistband does not. That is why so many briefs die in the same recognisable way, with the body of the garment still perfectly sound and the band gone slack and wavy, no longer able to return to the length it was cut to. Not worn out. Heat damaged, by me Buy It Once: The Durability Guide to Briefs That Last Years.
Cotton briefs air dry in a few hours. Synthetic ones dry in about one. There has never, in the history of my life, been an emergency that this cost me. The printed pairs went in with all the rest, which is why a reindeer somebody gave me in good faith was a rumour of a reindeer by the following December In Defence of Christmas Pants.
To the pair I sent through a sixty degree wash with the bedding
This one was not laziness. This one was a theory, which is worse.
I had decided, on no evidence, that underwear needed washing hot to be properly clean, and that anything less was a compromise made by people with more patience than me. So in you went, with the sheets and the towels, on the long hot cycle, and you came out clean and slightly smaller and never quite the same shape again.
The theory is not entirely wrong, which is the annoying part. Higher temperatures do kill more microorganisms, and there are genuine reasons to wash at sixty degrees: illness in the house, certain fungal problems, cloth nappies. But for ordinary laundry a good detergent at forty does the hygiene job perfectly well, particularly a powder or tablet containing an oxygen bleach system, which is built to work at lower temperatures precisely because nobody wants to boil their clothes any more.
Sixty degrees does three things to a brief. It accelerates the same elastic damage the dryer does. It shrinks cotton that was not pre-shrunk, unevenly, so the garment comes back a different shape rather than a smaller one. And washing you with towels meant an hour of being scrubbed by heavy loops of terry, which is abrasion, which is how fine cotton starts pilling.
Wash underwear at thirty or forty, with other light things. The full method is a short list and it works How to Wash Underwear Properly.
To the pair I softened
You were a technical brief, a fine synthetic knit bought for long days on my feet, and you did that job beautifully for about four months.
Then I bought fabric softener, because the bottle was blue and it was on offer, and I put it in the machine every wash for a year, and could not work out why you had stopped wicking.
Fabric softener works by depositing a thin film of conditioning agents onto fibres. On a bath towel this is a mild nuisance, since it reduces absorbency. On a performance fabric it is a lobotomy. The entire point of a wicking knit is that it moves moisture through itself and lets it evaporate; coat it in something water repellent and it holds the sweat where it is instead. Worse, the residue builds up over repeated washes and gives odour compounds something to cling to, which is the exact opposite of what the fabric was engineered to do The Sweat Article: Moisture-Wicking Fabrics, Explained Properly.
You did not need softening. Nothing needs softening. If your cotton is coming out stiff, the causes are usually too much detergent, hard water or an overloaded drum, and half a cup of white vinegar in the rinse will do more than the blue bottle and leave nothing behind.
To the pair I asked to run a marathon
You were never the wrong garment. You were the wrong garment for that.
You were a heavyweight cotton rib brief, genuinely superb under a suit or on a sofa, and I put you under running shorts at eight in the morning in September and asked you to cover forty two kilometres, because you were the pair I liked best and I had decided that liking them best was the relevant criterion.
Cotton absorbs a great deal of moisture and then holds it. A wet cotton seam under load, moving against skin, for four hours, is not a comfort problem. It is an injury, and by about thirty kilometres I was running in a way that had nothing to do with my legs. I have never told anyone how the last hour of that race actually went.
The lesson is not that cotton is bad. Cotton is excellent, in air, at rest, in a temperate room. It is that endurance sport is one of the few contexts where the fabric has to be synthetic or merino, and where flatlock seams and a cut that sits against you without shifting stop being refinements and become the specification Right Support, Right Sport: What to Wear for What You Do. It helps considerably if the leg is long enough to keep skin from meeting skin Underwear for Big Thighs: The Chafing Problem Solved. One pair kept exclusively for running costs less than a single physiotherapy appointment merino running brief.
To the pair I used to varnish a chair
You did not deserve the promotion and you certainly did not deserve the ending.
I need to be careful here, because there is a defensible version of this. A brief that has genuinely reached the end of its life, waistband gone and cotton thin, makes an outstanding cloth. It is soft, it is lint free after a hundred washes, it holds solvent well, and cutting it up is a better fate than landfill. I have no regrets about the ones I retired properly.
You, however, were about eighteen months old and had one hole in a side seam, roughly the length of a grain of rice, which any adult with a needle could have closed in ninety seconds. I did not do that. I reached into the drawer looking for a rag, saw the hole, made a decision I did not examine, and by the end of the afternoon you were stiff with wood stain and beyond appeal.
Learn to close a seam. A split side seam, a lifted hem and a waistband coming away from the body are all repairable with a needle, ordinary thread and a stretch stitch, which in hand sewing just means a small zigzag rather than a straight line, so the repair moves with the fabric instead of snapping the first time you put the thing on. Ten minutes. The garment gets years Anatomy of a Brief: Every Panel, Seam and Stitch Explained.
To the good pair I kept for best
You are the one I feel genuinely bad about, because you never got to do anything at all.
You were a gift, in a box, from a house that knows exactly what it is doing, and you were noticeably nicer than anything else I owned. So I put you at the back of the drawer, on the grounds that you were too good for a Wednesday, and you sat there through several Wednesdays, and then several years.
When I finally took you out for an occasion that felt sufficiently important, the elastic had gone. Not from use. From sitting still.
This is the part nobody tells you. Elastane degrades on its own, through oxidation, and heat, light and humidity all speed it up. A drawer in a warm bedroom is a slow oven. The garment you are saving is not preserved by being saved; it ages quietly in the dark while the cheaper pairs you actually wear get rotated, washed, rested and used up honestly. Nothing in a drawer improves with keeping.
Wear the good pair. Wear it on a Wednesday. Buy fewer things and use all of them, in rotation, which is also the fastest way to learn what you actually like The Drawer Audit: How Many Briefs You Need and When to Replace Them.
To the white pair I tried to make whiter
The bleach incident.
You had gone the colour white cotton goes, not grey exactly and not cream exactly but unmistakably not white any more, and I wanted the original back. So I found a bottle of household bleach under the sink, did not read anything, did not dilute anything meaningfully, and left you in it for what I would describe as a while.
You came out yellow. Yellower than you went in.
Two things happened, and both are worth knowing. Chlorine bleach attacks elastane and nylon directly, which is why the waistband and the leg elastic went brittle first. And chlorine reacts with the optical brightening agents manufacturers use to make white fabric read as bright white; disturb those and the fabric can turn distinctly yellow, which cannot be reversed by adding more bleach, a thing I know because I tried.
The correct method for greying whites is oxygen bleach, sold as a powder, dissolved in warm water, with the garment soaked for a few hours and then washed normally. Slower, duller, effective, and it will not eat the elastic Why Underwear Is White. Keep white cotton out of the same wash as anything dyed, since much of the greying is transferred dye rather than dirt white cotton brief.
What I am actually apologising for
None of this is really about the garments. Obviously it is not about the garments. A brief has no feelings and does not know it has been let down.
It is about the fact that for most of my adult life I treated the things I own as a problem to be got through rather than objects with lives of their own, and underwear was the extreme case, because it is cheap enough to replace without thinking and hidden enough that nobody would know. Which is precisely why it is the honest test. Anyone will look after a watch.
What changed was not virtue. It was noticing that the alternative is more pleasant. Washing at forty and hanging things up takes about as long as not doing it. Sewing a seam is quietly satisfying in a way that scrolling is not. A drawer where everything is in rotation and everything still snaps back is a small piece of order in a life that does not offer much of it Against the Multipack.
There is also this. You put these things on at seven in the morning, half awake, before anything else has happened, and they are the first decision of the day and the only one nobody else has any say in. Reaching into a drawer and finding something that fits properly, has held its shape and has been looked after is a genuinely good thirty seconds. It is a small pleasure, available every single day, which very few pleasures are.
So: to all of you, and to the eleven years of tumble drying in particular, I am sorry. The current lot are treated better. Some are older than they look, and none of them are being saved for anything.
It turns out this is not a rare affliction. Readers have written in defending pairs well past retirement, and at least one of those defences is better than anything above it on this page: see The Postbag: The Home Front.
Questions people ask
What temperature should you wash underwear at?
Thirty or forty degrees is right for almost all underwear. A good detergent, particularly a powder or tablet with an oxygen bleach system, cleans effectively at those temperatures and is gentle enough to preserve the elastic. Reserve sixty degrees for specific situations such as illness in the household or a fungal infection, and accept that repeated hot washing shortens the life of the waistband and can shrink cotton unevenly.
Does the tumble dryer really ruin underwear?
Yes, and it is the single most damaging thing most people do to their underwear. Heat degrades elastane and rubber elastic, so a dryer causes more loss of recovery in one cycle than weeks of wearing. The typical result is a garment whose fabric is still sound but whose waistband has gone slack and wavy. Cotton briefs air dry in a few hours and synthetics in about one, so line drying costs very little and greatly extends the life of the garment.
Why should you not use fabric softener on underwear?
Fabric softener leaves a thin conditioning film on the fibres. On performance fabrics this blocks the wicking action, so sweat sits on the skin instead of moving through the fabric and evaporating, and the residue builds up over repeated washes and holds odour. On cotton it reduces absorbency. If cotton feels stiff, use less detergent, do not overload the drum, and add a little white vinegar to the rinse instead.
How do you get white briefs white again?
Use oxygen bleach, sold as a powder, dissolved in warm water, with the garment soaked for several hours before a normal wash. Avoid household chlorine bleach: it attacks elastane and nylon, and it reacts with the optical brighteners in white fabric, frequently turning the garment yellow rather than white. Wash whites separately from anything dyed, since much greying is transferred dye rather than dirt.
Do briefs deteriorate if you never wear them?
Yes. Elastane degrades through oxidation regardless of use, and heat, light and humidity all accelerate it, so a pair stored for years in a warm drawer can have poor elastic recovery the first time it is worn. Storing underwear does not preserve it. Keep the whole drawer in rotation so every pair is used, washed and rested evenly, and replace on waistband recovery rather than appearance.