How to Store Outdoor Cushions Over a Canadian Winter

Quick answer: Clean outdoor cushions before you store them, then let them dry completely, foam and all. Store them indoors somewhere dry and ventilated, such as a basement, closet or heated garage, standing on edge or loosely stacked. Use breathable fabric bags, never sealed plastic. In spring, air them out, brush them off and press-test the foam.

A Canadian winter is long, and it is hard on anything left outside. Snow load, freeze-thaw cycles, ice under the covers and months of damp all take their toll. A cushion left on the patio from November to April usually comes back in spring stained, flattened and smelling of mildew. Put away properly, the same cushion looks almost new when the deck reopens. The work takes an afternoon in the fall, and the method is the same whether you are in Calgary, Halifax or on the wet coast of BC.

Why winter storage matters

Sunbrella and other good outdoor fabrics handle sun and rain well, but winter is a different test. Snow sits on cushions for weeks and melts slowly into the foam. Moisture trapped inside freezes and thaws over and over. Dirt, pollen and leaves left on the fabric in the fall give mildew something to feed on all winter. And a cushion buried under snow can be crushed flat for months.

Bringing cushions in protects the fabric, the foam and the stitching. It also means you are not digging them out of a snowbank in March.

Step 1: Clean before you store

Never store dirty cushions. Whatever is on the fabric in October will still be there in April, with a winter's worth of time to settle in.

Brush and spot clean

1. Brush off leaves, pine needles, pollen and dirt with a soft brush.
2. Mix a little mild soap into lukewarm water.
3. Work it into marks with a sponge or soft brush, and let it soak in briefly.
4. Rinse thoroughly. Leftover soap attracts dirt.

Machine wash Sunbrella covers

Sunbrella covers can be unzipped and machine washed on a gentle cycle with mild detergent. Air dry them rather than tumble drying. It is a good idea to put the covers back on while still slightly damp, so they ease back into shape over the foam, but make sure the whole cushion is fully dry before it goes into storage.

Stubborn stains and mildew spots

For mildew or tough stains on Sunbrella, follow Sunbrella's own care guidance for a diluted bleach and mild soap solution. Our Sunbrella fabric guide sets out the method. Rinse very thoroughly afterward. Check the care guidance for any other fabric before using bleach on it.

Marine vinyl

Wipe boat cushions and marine vinyl with a damp cloth and mild soap, then dry the surface. Avoid harsh solvents.

Step 2: Dry completely

This is the step most people rush, and it is the one that matters most. A cushion that feels dry on the surface can still be damp in the middle of the foam. Put away damp, it will grow mildew in storage.

• Stand cushions on edge in a breezy, sunny spot, or indoors near good airflow.
• Turn them every few hours so every face and edge dries.
• Press the centre of the cushion with your palm. If you feel any coolness or damp, give it more time.
• Pick a dry run of weather in September or early October. Late fall in much of Canada is too cold and damp to dry cushions outside.

Cushions with dry-fast foam dry in hours, because water drains straight through the open-cell foam. Cushions with standard foam can take a day or two.

Step 3: Store them dry and ventilated

Where to store

The best spot is somewhere dry, ventilated and above freezing: a basement storage room, a spare closet, under a bed or a heated garage. An unheated shed or garage works if it stays dry, but keep cushions off the concrete floor, where cold and damp collect. At the cottage, a dry closet in the main building beats the boathouse.

How to store

• Stand them on edge or stack them loosely. A tall stack crushes the bottom cushions for months.
• Use breathable bags. Cotton duvet covers, old pillowcases or purpose-made breathable storage bags keep dust off and let moisture escape.
• Avoid sealed plastic. Plastic bins and garbage bags trap any remaining moisture, and temperature swings cause condensation inside.
• Keep pests out. Mice like a cozy cushion for the winter. Store off the floor, and check a cottage storage spot before you leave.

Covered furniture outside?

If you truly have no indoor space, store cushions inside a deck box or under a furniture cover only after they are fully dry, and keep them raised off the deck. Check them once or twice over the winter. This is a fallback rather than the best option, especially in snowy regions where moisture builds up under covers.

Foam care over winter

Foam is resilient, but long-term compression is not good for it. Avoid placing heavy boxes on top of stored cushions. If foam has been squashed for months, give it a day or two at room temperature in spring to recover. Standard foam can feel firmer when cold, so let it warm up before judging the feel.

Spring refresh

When the snow is gone and the deck is dry, bring the cushions out in stages:

1. Air them out. Unbag them and let them breathe for a day.
2. Brush and spot clean. Remove any dust from storage.
3. Press-test the foam. Press the centre of each seat cushion. If it springs straight back, it is fine. If it stays dented or feels thin, it is time for new foam.
4. Check the covers. Look for faded panels, worn piping and sticking zippers.
5. Check the ties. Spring winds on a lake or open deck will move any cushion that is not tied down.

When storage is not enough

If a cushion has a musty smell that cleaning does not shift, or the foam is crumbling, it is past saving, and a complete new cushion is the simplest fix. If the foam is fine but the fabric is tired, order new outdoor cushion covers sewn to your foam size. Sunbrella fabric carries a 5-year warranty and our workmanship 2 years; see our warranty for details.

Ordering over the winter means new cushions are ready before the first warm weekend. Most orders are made in 2–3 weeks, with free delivery across Canada and duties and GST/HST paid.

Frequently asked questions

Can outdoor cushions stay outside in a Canadian winter?

It is best not to leave them out. Snow, ice and long periods of damp shorten the life of the foam and invite mildew. Clean, dry and store them indoors for the winter.

Should I store outdoor cushions in plastic bags?

No. Sealed plastic traps moisture and causes condensation. Use breathable fabric bags or covers instead.

Can I store cushions in an unheated garage or shed?

Yes, if it stays dry. Keep cushions off the floor, stand them on edge and protect them from mice.

How do I know if my cushion foam needs replacing?

Press the centre of the cushion. If the foam springs back, it is fine. If it stays dented, feels thin or smells musty after cleaning, replace it.

Can I machine wash Sunbrella cushion covers before storing them?

Yes. Wash on a gentle cycle with mild detergent, air dry, and make sure the whole cushion is completely dry before it goes into storage.