How do I dry and store a tent so it does not go mouldy?

The polyurethane coating that makes a flysheet waterproof is broken down by moisture over time, a process called hydrolysis, and mould accelerates it dramatically. A tent packed wet at the end of a bank holiday and left in a garage until next summer very often comes out sticky, smelling of damp, and permanently past saving. It is the single most common way tents are destroyed.

What you'll need

• Space to hang or pitch the tent
• A soft brush and mild non-detergent soap
• A fan (optional)
• A mould treatment suitable for tent fabric (optional)

Step by step

1. Accept that a wet pack-away is sometimes unavoidable.Nobody dries a tent in the rain at a campsite. What matters is what happens next: get it out and open within a day or two at the outside, and sooner in warm weather.
2. Separate everything as soon as you are home.Flysheet, inner, groundsheet, poles and pegs all come out of the bag. A rolled tent dries from the outside inwards and the middle stays wet for days.
3. Pitch it if you can.In a garden, a garage or any space big enough. Pitched, air reaches every surface and it dries in a few hours. Even a partial pitch over furniture is better than a heap.
4. Hang it if you cannot pitch it.Over a washing line, a bannister, a clothes airer or a couple of chairs, turning it every hour or two so the folds change. Overlapping fabric is where mould starts.
5. Dry the inner, the groundsheet and the bag as well.The groundsheet and the stuff sack hold the most water and are the parts people forget. A dry tent in a damp bag is a damp tent by the weekend.
6. Clean off mud and organic matter before storing.Cool water, a soft brush, and a mild non-detergent soap on the dirty areas only. Grass, sap and bird mess feed mould. Never use household detergent or fabric conditioner, which strip and contaminate the coating.
7. Dry the pegs and poles too.Wipe pegs and let them dry before bagging, or they rust in the bag and stain the fabric. Wipe poles and check for grit in the ferrules.
8. Store it loosely, not tightly rolled.A large bag, a pillowcase or a plastic crate with the tent loosely folded is far better than the original compression sack. Repeated tight folds along the same lines crack the coating.
9. Choose the right place.Cool, dark, dry and ventilated. A loft that reaches 40 degrees in summer accelerates coating breakdown; a damp garage floor or a shed that condenses does the opposite kind of damage. Indoors, in a cupboard, is best.
10. Treat mould that has already appeared.Brush off the growth dry, outdoors, then wash the affected area with a mild soap or a proprietary tent cleaner and rinse. Some specialist products kill the spores. Do not use bleach or household mould remover, which destroy the fabric and its coating.
11. Accept what mould has already cost.The black spotting itself usually cannot be removed, the smell often lingers, and the coating underneath the spots is likely damaged. You can make a mouldy tent usable; you cannot make it new.
12. Check it before the season, not the night before.Pitch it in the garden in spring. It gives you time to reproof, seal a seam or order a pole section.

Tips

• Pack the flysheet last on top at the campsite, so it is the first thing out and the easiest to hang up when you get home.
• A cheap dehumidifier or a fan in a garage will dry a tent overnight in poor weather.
• If a tent smells of damp, it has already started. Deal with it immediately rather than putting it back in the bag.

Common mistakes

• Leaving a wet tent packed for weeks — Mould grows within days in a warm bag and it digests the polyurethane coating, which is the waterproof layer. The result is a sticky, foul-smelling flysheet that leaks, and none of that damage can be reversed.
• Cleaning a mouldy tent with bleach or household mould spray — Both attack the fabric and the coating far faster than they attack the mould, and they will leave a tent weaker and less waterproof than before. Mild soap, brushing, and a fabric-safe treatment are the only sensible options.

If it doesn't work

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