How to dry a car cover in winter

Why this matters more than it sounds

A cover comes off wet. It goes into a trunk or a garage corner folded. It stays there until tomorrow evening, when it goes back onto your car.

Within a week or two of that cycle you have mildew, and the inner face of a mildewed cover is textured with growth and holds grit far more readily than clean fabric. That surface then spends every night against your clear coat.

There is a second, quieter problem. A damp cover left folded in the cold freezes into a solid block, and unfolding a frozen cover cracks the coating on the outer layer — which is what was making it weather-resistant.

Four ways to dry one when it is cold

1. Hang it in the garage

The best answer if you have the space. A couple of hooks in the ceiling joists, or a rope run across the back of the garage, and the cover hangs open rather than folded.

The key is that it hangs open. Draped over a workbench it dries on one side and stays wet on the other. Air needs to reach both faces.

A garage that is sealed and slightly above freezing dries a cover overnight. One that is at outside temperature with a gap under the door does not — which is one more argument for sealing the door.

2. Fit it inside out for the last hour

If the car has been running, there is residual heat in the panels. Put the cover back on inside out for an hour after you get home and the inner face dries against a warm surface.

It is a partial measure and it works better than it sounds, and it costs nothing.

3. Shake it out hard, then hang it anywhere

Most of the water on a coated cover is sitting on the surface rather than absorbed. Shaking it out properly before it goes anywhere removes a surprising proportion of it, and it also removes the grit — which is the other reason to do it.

4. Two covers, alternating

If you are covering a car through a genuinely wet winter, two cheaper covers used on alternate days beats one expensive one used wet. Each gets a full day and night to dry.

It is not elegant. It is what people who actually sustain the routine end up doing.

If it has already mildewed

1. Check the manufacturer’s care instructions first. Some covers can be machine washed on a gentle cycle; some cannot, and washing one that cannot destroys the coating.
2. Wash it outdoors on a mild day with a mild detergent and a soft brush, on a clean surface — not on gravel, which embeds grit in the inner face.
3. Rinse thoroughly. Detergent residue on the inner face is its own problem against paint.
4. Dry it completely before it goes near the car.
5. If the inner face is visibly degraded, replace it. A rough inner face is an abrasive, and a $70 cover is much cheaper than paint correction.

Storing it for the summer

Wash it, dry it completely, and store it somewhere breathable — a cotton bag, a cardboard box, or the bag it came in if that bag is not sealed plastic.

Then check it in September before you need it, because discovering the problem in November means going without.

The same logic applies to a windshield cover, which is much smaller and much easier to dry — a hook by the garage door is genuinely all it needs, and that ease is part of why a windshield cover is the one people keep using.