What pre shrinking means for your size

Short answer: Short answer: Preshrunk fabric has already shrunk during production. That is why the garment changes only a little in the first wash at home, regardless of temperature and drying method.

Why fabric shrinks in the first place

During production the yarn gets stretched several times, and that tension stays in the fabric after weaving or knitting. The first time the fabric meets heat and water, the tension releases and the stitches pull back toward their natural resting shape. So it is not the fiber getting smaller, it is the structure settling back into place.

What the manufacturer can do about it

With preshrinking, the fabric is run through heat and moisture already during production, before it is even cut and sewn. That way most of the shrinking has already happened before the garment is finished, and the size stays far more stable when the customer washes it at home for the first time following normal care.

How you can reduce shrinkage yourself

Wash at thirty degrees and dry without heat, and bamboo viscose shrinks very little regardless of whether the fabric is preshrunk or not. If you are unsure about a garment, wash it alone the first time and measure it afterward. See bamboo t-shirts for men for examples that hold their size well.

The difference between preshrunk and untreated fabric

An untreated fabric can in theory shrink more at the first wash, because all the tension from production still sits in the yarn. A preshrunk fabric has already released most of that tension during production. The difference is most noticeable in garments sewn close to the body, where even a few percent makes a visible difference.

Why bamboo viscose shrinks less than cotton

Bamboo viscose has a different fiber structure than cotton and generally reacts less strongly to water and heat. That means even untreated bamboo viscose typically shrinks less than comparable untreated cotton. See bamboo clothing for men and bamboo clothing for women for examples where fit stays more predictable over time.

What happens if you wash too hot

High heat increases both the speed and the extent of shrinkage, because more energy releases the tension in the fabric all at once. A garment that would barely shrink at thirty degrees can shrink noticeably more at eighty. That applies to both preshrunk and untreated fabric, just in different amounts and at different speeds.

Why you should wash a new garment alone

Even preshrunk fabric can release a little extra tension at the very first wash at home, especially if the garment sat packed for a long time before being sold. Washing it alone also keeps any excess dye from rubbing off on other clothes in the same load, while you check whether the fit holds up.

What shrinkage means for fit over time

After the first wash, a preshrunk garment usually settles, and later washes change it only very little from then on. That is why the fit you notice after that first wash is, for the most part, the fit you can expect the garment to keep throughout the rest of its lifetime and regular use.

Should you size up just to be safe

No, not as a rule. With correct care, meaning cold washing and no unnecessary heat when drying, shrinkage on preshrunk bamboo viscose is too small to justify sizing up. Instead choose the size that fits now, and follow the care instructions consistently throughout the garment's entire lifetime.

Frequently asked questions

How do I know if a fabric is preshrunk

It is rarely stated directly on the garment or the care label. Wash cold regardless, so it matters less whether the fabric is preshrunk, because shrinkage stays minimal either way in practice.

How much does bamboo viscose typically shrink when washed

Typically a couple of percent at thirty degrees, and more if washed or dried at high heat. Preshrunk fabric generally shrinks less than untreated fabric under the same conditions.

Should I buy a size up just to be safe

No. With correct care, meaning cold washing and no unnecessary heat, shrinkage is too small to justify sizing up in advance for a garment that already fits well.

You can find the full range at Bamboo-Clothing.com.