Why do natural fibres shrink more than synthetics?

Natural fibres like cotton, wool, and linen have coiled fibre structures that relax and then contract when exposed to heat and moisture. Synthetic fibres like polyester have heat-set structures that are more resistant to this contraction.

Can I unshrink a garment that's already shrunk?

For mild shrinkage in knits, soaking in warm water with a small amount of fabric conditioner and then gently stretching the item flat while damp can recover some size. Severe shrinkage — especially in wool that has felted — is generally not reversible.

Does cold washing always prevent shrinkage?

It significantly reduces the risk. Heavy agitation in a cold cycle can still cause some shrinkage in very delicate fabrics. Using a gentle cycle as well as cold water gives the best protection.

What's the best way to dry wool garments?

Lay flat to dry on a clean towel or mesh drying surface. Hanging wet wool pulls the fibres out of shape under gravity. Never put wool in the tumble dryer unless the care label specifically says it's safe.

Are mesh laundry bags actually useful?

Yes, for delicates specifically. Mesh bags reduce friction and abrasion in the wash cycle, which protects fine fibres from the mechanical stress that contributes to both shrinkage and pilling.

Woman standing at a laundromat with rows of washing machines

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How to Prevent Clothes from Shrinking

February 10, 20263 min readBy Johnson Yu

Shrinkage is one of those laundry outcomes that's mostly preventable once you understand what causes it. The common assumption is that washing shrinks clothes, but the dryer is usually more responsible than the washing machine. At our Maple Ridge facility, temperature and cycle selection are matched to the fabric type for every single load — and the results speak for themselves in garments that hold their shape wash after wash.

Why Clothes Shrink

Natural fibres — cotton, wool, linen, cashmere, and bamboo among them — have coiled molecular structures that relax under heat and moisture. When the heat source is removed, those structures contract. If they contract while the fabric is unrestrained in a tumble dryer, the garment ends up smaller than it started.

Synthetics like polyester and nylon are less vulnerable because their fibre structure is heat-set during manufacturing and doesn't have the same moisture-responsive contraction. Blended fabrics fall somewhere in between, depending on the ratio of natural to synthetic content.

Cold Water as the Foundation

Washing in cold water is the most straightforward shrinkage prevention habit. The lower temperature means there's less heat energy available to relax fibre structures, so contraction is much less likely to occur during the wash cycle.

Modern detergents are designed to perform well at cold temperatures, so you're not sacrificing cleaning effectiveness. For everyday cotton, jersey, linen, and casual knitwear, cold water washing is both safe and effective.

Cycle Selection: Agitation Matters Too

Heat isn't the only factor — mechanical agitation also stresses fabric fibres. A high-agitation regular cycle is harder on natural fibres than a gentle or delicate cycle. For knits, lightweight blouses, and items made from fine natural fibres, selecting the gentler cycle reduces both the shrinkage risk and the wear-and-tear on the fabric over repeated washing.

The Dryer Is the Greater Risk

Most significant garment shrinkage happens in the dryer rather than the washing machine. High dryer heat can shrink a cotton garment noticeably in a single cycle, and the cumulative effect of repeated high-heat drying is what turns a well-fitting shirt into something that's difficult to pull on.

Use low heat for garments that can go in the dryer. Better still, pull items out while they're still slightly damp and allow them to finish air drying naturally. This reduces total heat exposure while still giving you the convenience of partly machine-drying the load.

For wool sweaters, structured knits, and anything with significant wool content, the tumble dryer is not appropriate unless the care label specifically indicates it's safe. Lay these items flat to dry — hanging them while wet allows gravity to pull the fibres out of shape, even if no heat is involved.

Mesh Bags for Extra Protection

A mesh laundry bag is a small investment that makes a real difference for delicate and fine-knit garments. The bag reduces friction between the garment and the machine drum and prevents snagging on zips and buttons in the same load. Less physical stress on the fibres means less contraction and pilling over time.

We select the right temperature, cycle, and drying method for every fabric type — book a pickup and protect your wardrobe from unnecessary shrinkage.

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Frequently asked questions

Why do natural fibres shrink more than synthetics?: Natural fibres like cotton, wool, and linen have coiled fibre structures that relax and then contract when exposed to heat and moisture. Synthetic fibres like polyester have heat-set structures that are more resistant to this contraction.
Can I unshrink a garment that's already shrunk?: For mild shrinkage in knits, soaking in warm water with a small amount of fabric conditioner and then gently stretching the item flat while damp can recover some size. Severe shrinkage — especially in wool that has felted — is generally not reversible.
Does cold washing always prevent shrinkage?: It significantly reduces the risk. Heavy agitation in a cold cycle can still cause some shrinkage in very delicate fabrics. Using a gentle cycle as well as cold water gives the best protection.
What's the best way to dry wool garments?: Lay flat to dry on a clean towel or mesh drying surface. Hanging wet wool pulls the fibres out of shape under gravity. Never put wool in the tumble dryer unless the care label specifically says it's safe.
Are mesh laundry bags actually useful?: Yes, for delicates specifically. Mesh bags reduce friction and abrasion in the wash cycle, which protects fine fibres from the mechanical stress that contributes to both shrinkage and pilling.