Cloth
A sheet is three choices stacked together: the fiber, the yarn spun from it, and the weave that crosses the yarns. Percale and sateen are weaves. Linen and cotton are fibers. Thread count is a tally of yarns in a square inch. This department explains each one and what it changes in the bed, so the words on a label stop blurring together.
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What is a sheet made of, from fiber to weave?
A fiber is spun into yarn, and yarns are woven into cloth. Each step changes how the sheet feels, and a label names only some of them.
Start with the fiber, because it decides how soft the sheet stays. Cotton and flax are the two you meet most on sheets. Longer fibers, which the trade calls long staple, spin into smoother yarn with fewer loose ends. Those loose ends are what work up into pills against your skin.
Then the yarn. A yarn can be one strand or several twisted together, which is called ply. Ply matters because it is the trick behind inflated thread counts.
Then the weave. Percale crosses one yarn over and one under. Sateen floats a yarn over several before it dips under. Most linen sheets use a plain weave, the same grid as percale, so a linen sheet and a percale sheet can share a weave and still feel nothing alike.
| Word on the label | What it names | What it changes |
|---|---|---|
| Cotton, linen, flax | The fiber | Heat, damp and strength |
| Pima, Supima, Egyptian | A long-staple cotton | How soon the cloth pills |
| Single-ply, two-ply | How the yarn is built | Whether a count is honest |
| Percale, sateen | The weave | Crisp or smooth, matte or shiny |
| Thread count | Yarns per square inch | Little, past a few hundred |
What does a sheet label have to tell you by law?
The fiber content by percentage, the country of origin and the business responsible. The weave word and the thread count carry no rule.
Sheets fall under the federal textile labeling rules, which list sheets among the beddings they cover. Those rules, in 16 CFR Part 303, ask for the fiber content, the business responsible and the country of manufacture. They also set how fiber names and percentages by weight must appear.
Extra words on a label have a rule too. Anything a seller adds must not be false, deceptive or misleading, and it must not crowd out the required facts. The country of origin always goes on the front side of the label, where you see it first.
Nothing in those rules defines percale or sateen, and nothing sets a thread count. So the fiber line is the part of a label a seller has to stand behind, and it is the line that tells you how soft the sheet will stay. When a page names a long-staple cotton but no variety and no country, it is selling an adjective.
What is percale, and why does it feel crisp?
Percale is a tight plain weave, one yarn over and one under. The grid leaves small gaps for air, so the cloth feels cool, dry and matte.
Every crossing in percale ties a yarn down. That gives the cloth its pressed-shirt feel against your skin, and it is why percale wears well in the wash. The same grid creases wherever it is folded, so a percale bed looks slept in within an hour. One reference puts the floor for the word at about 180 threads per square inch (Wikipedia).
Percale starts firm. It softens as washing relaxes the yarn over a few months, and washed or brushed percale skips that wait at some cost to the crisp hand.
Our guide What is percale, and how does the weave feel and wear? covers the count band, the cotton names and why four-figure counts are arithmetic.
Why does sateen feel smoother than percale?
Sateen floats each yarn over several others, so more of it lies flat against your skin. The same floats snag and pill sooner than percale.
Sateen uses the satin weave with spun yarn in place of filament (Wikipedia). The usual float is four over and one under. That puts a smooth, faintly shiny face on one side of the sheet. Fewer crossings also mean a yarn can be pulled loose more easily, by a rough heel or a cat's claw.
Lab work on cotton weaves found satin let more air through than plain weave at the same density (PMC). So the extra warmth people feel in sateen likely comes from heavier construction rather than the float, and a light sateen can feel cooler than a heavy percale.
Our guide What is sateen, and why does it feel smoother than percale? sorts out the count claims sateen listings make.
How does linen differ from cotton percale?
Linen is a fiber, flax, and percale is a weave. Flax is pulled, retted and combed before spinning, and the cloth is heavier and creases.
Flax stalks are pulled, then retted, which lets bacteria break down the pectin that binds the fibers (Wikipedia). The woody core is crushed away and the short fibers are combed out. Only then is the long fiber spun and woven.
Compared with cotton, linen is stronger and moves heat better, but it is less elastic and creases easily (Materials, via PubMed Central). That makes a linen bed feel cool and dry in humid weather. It also looks rumpled by morning, and nothing short of an iron changes that.
Linen is sold by weight in grams per square meter, not by count. Weight is cut and weighed from the cloth, so no ply trick inflates it.
Our guide How is linen made into sheets, and how does it differ from cotton percale? walks through the process, the weight figures and the flax certificates.
What does thread count measure, and what does it leave out?
It counts yarns in one square inch. Plies can be multiplied into a bigger figure, and past a few hundred the number says little about the cloth.
FTC staff told the industry that a sheet of 300 thread count, two-ply yarn should not be sold as 600 (Home Textiles Today). Consumer Reports found its top-scoring percale had a count of only 280 (Consumer Reports).
There is a test method for counting, too. ASTM D3775 measures end and pick count on woven fabric. Nobody at a checkout page has a pick glass, so the label is taken on trust.
So the count is a filter. The fiber, the ply and the weave tell you more once a sheet clears a few hundred. Our guide Is thread count a marketing number, and what should you read instead? sets out what to read in its place.
What do sheet sellers print about their cloth, and what do they leave out?
Most print a thread count or a fiber name. Almost none print the yarn ply, which is the one fact that shows whether a count is honest.
The guides in this department each count what seller pages state. Read together, the counts show one gap. Sellers print the number that sells, and they rarely print the fact that would let you check it.
On percale, half the pages printed a count and none printed ply. On sateen, three of eleven listings claimed more than 600, and only one named its ply. Linen sellers did better, because a weight in grams per square meter cannot be inflated by twisting yarns together.
So the fiber line and the weight, where there is one, are the figures to trust. They are the ones that tell you how the sheet will feel against your skin a year from now.
| Guide | Pages read | What most printed | What almost none printed |
|---|---|---|---|
| Percale | 12 | A count, or a cotton type | Yarn ply |
| Sateen | 11 | A count, most often 600 or below | Yarn ply |
| Linen and percale | 14 | Weight for linen, count for percale | Weight for percale |
How much does the sheet change how warm a bed feels?
Less than the duvet and how much of you it covers. The weave works on the thin layer of air at your skin, which changes how dry you feel.
Researchers put a heated manikin in a climate chamber and tested whole bedding systems. Total insulation ranged from 1.06 to 5.71 clo, by posture, coverage and materials (Waseda University). The sheet is one thin layer inside that range. Sticking a leg out from under the duvet changes more than swapping the sheet.
Sleep trials have compared fibers, not weaves. A systematic review of sleepwear and bedding found nine studies, all comparing fiber types (Journal of Sleep Research). Nobody has trialled percale against sateen in people's beds. A weave claim about cooling is reasoning from structure, and the pages here say so when they make one.
What does Top Sheet have under this heading?
- How is linen made into sheets, and how does it differ from cotton percale?
- Is thread count a marketing number, and what should you read instead?
- What is percale, and how does the weave feel and wear?
- What is sateen, and why does it feel smoother than percale?
Common questions
Is percale a fiber or a weave?
A weave. Percale is a plain weave, one yarn over and one under, usually in cotton. The fiber is named separately on the label.
Is sateen the same as satin?
No. They share a structure but not a yarn. Sateen uses spun yarn, usually cotton, and satin uses filament yarn, which feels slicker.
Why do linen sheets list grams per square meter?
Flax yarns are thicker and less even than combed cotton, so a count would mislead. Weight is cut and weighed from the cloth, and plies cannot inflate it.
Does a higher thread count mean a softer sheet?
Not past a few hundred. Higher counts there usually mean finer, weaker yarn or plies counted separately. Long-staple fiber does more to keep a sheet soft.
What does long staple mean on a cotton sheet?
The cotton fibers are longer than ordinary cotton. Longer fibers spin into smoother yarn with fewer loose ends, so the sheet stays soft and pills later.
Sources
Top Sheet's references for this piece, set out in citation order with the heading each one sits under.
- 16 CFR Part 303 (ecfr.gov), sits under “What does a sheet label have to tell you by law?”.
- Wikipedia (en.wikipedia.org), sits under “What is percale, and why does it feel crisp?”.
- Wikipedia (en.wikipedia.org), sits under “Why does sateen feel smoother than percale?”.
- PMC (pmc.ncbi.nlm.nih.gov), sits under “Why does sateen feel smoother than percale?”.
- Wikipedia (en.wikipedia.org), sits under “How does linen differ from cotton percale?”.
- Materials, via PubMed Central (ncbi.nlm.nih.gov), sits under “How does linen differ from cotton percale?”.
- Home Textiles Today (hometextilestoday.com), sits under “What does thread count measure, and what does it leave out?”.
- Consumer Reports (consumerreports.org), sits under “What does thread count measure, and what does it leave out?”.
- ASTM D3775 (astm.org), sits under “What does thread count measure, and what does it leave out?”.
- Waseda University (waseda.jp), sits under “How much does the sheet change how warm a bed feels?”.
- Journal of Sleep Research (onlinelibrary.wiley.com), sits under “How much does the sheet change how warm a bed feels?”.