How to get rid of Mould or Mildew from a Tent or Awning

Mould and mildew are common problems for tents and awnings, often caused by packing them away damp. Left untreated, they can leave unsightly black stains, unpleasant odours, and even compromise waterproofing. If you've discovered mould on your tent or awning, don't panic—this guide will walk you through how to safely clean it and prevent future issues.

Why Does Mould Develop on Tents and Awnings?

Mould thrives in damp, humid conditions. If a tent or awning is packed away before it has fully dried, spores can multiply, leading to:

• Musty or ammonia-like odours (often compared to cat urine)

• Black, brown, or green stains

• Weakened waterproofing due to damage to the fabric's protective coating

Once mould takes hold, it can be difficult to remove, but acting quickly can help prevent further damage.

Step-by-Step Guide to Cleaning Mould from a Tent or Awning

Before you start cleaning, check the extent of the mould. If the fabric has a strong ammonia smell, it may already be too damaged to restore fully. However, for mild to moderate cases, follow these steps:

1. Choose a Suitable Cleaning Solution

Avoid harsh chemicals like bleach or washing-up liquid, as these can damage the tent’s waterproof coating. Instead, use one of the following:

• Milton Sterilising Fluid (1 part Milton to 10 parts water)

• White vinegar (1 part vinegar to 3 parts water)

• Specialist tent cleaners like Nikwax Tent & Gear SolarWash

2. Set Up Your Tent or Awning

• Choose a dry, sunny day if possible.

• Fully pitch the tent or awning so you can access all areas.

• If only part of the fabric is affected, lay it out flat.

3. Apply the Cleaning Solution

• Use a clean sponge or cloth to gently apply the solution.

• Test on a small, inconspicuous area first to check for any fabric discolouration.

• Avoid scrubbing too hard, as this can wear down the waterproof coating.

4. Rinse Thoroughly

• Use clean water to rinse the fabric well, ensuring no cleaning residue is left behind.

• For stubborn mould, repeat the cleaning process rather than using stronger chemicals.

5. Dry Completely

• Leave the tent or awning fully erected to air dry.

• If drying indoors, ensure good ventilation.

• Never store the tent while damp.

Things to Avoid / Things to Do

• Avoid standard household cleaners – Washing-up liquid, bleach, and general-purpose cleaners can strip away waterproof coatings and weaken fabric over time.

• Always test first – Before applying any cleaning solution, test a small, hidden section of fabric to check for unwanted effects.

• Inspect taped seams – If mould has spread to the taped seams, it can cause them to deteriorate. Once damaged, these seams are difficult to repair, and reproofing may not restore waterproofing effectively.

• Never pack away damp – Even a slightly damp tent or awning can develop mould, leading to lasting damage. Always air dry completely before storage.

Reproofing After Cleaning

Cleaning can strip away some of the tent’s waterproofing, so it’s important to reproof it after treatment:

• Use a tent reproofing spray like Fabsil.

• Apply evenly and allow to dry fully before packing away.

👉 Learn how to reproof your tent

When to Replace a Mould-Damaged Tent

If your tent or awning has extensive black staining or a strong ammonia-like smell, it may be beyond repair. Signs it’s time for a replacement include:

• Widespread mould growth affecting multiple areas

• Peeling or damaged waterproof coating

• Brittle or weakened fabric

If you need a replacement, check out our full range of tents and awnings for high-quality options.

How to Prevent Mould in the Future

Prevention is always easier than removal. Follow these tips to keep your tent or awning mould-free:

• Always pack away dry – if you must pack it damp, air it out as soon as possible.

• Store in a cool, dry place – avoid garages or sheds prone to condensation.

• Use a breathable storage bag – avoid plastic bags that trap moisture.

• Check regularly – inspect your tent before each trip for any signs of mould.

For more tent maintenance tips, read our guides on How to Store Your Tent Over Winter and How to Waterproof or Reproof a Tent.

Final Thoughts

Taking care of your tent or awning properly will extend its lifespan and ensure it performs well on every trip. If mould does develop, act fast with the right cleaning methods, and always remember to reproof the fabric afterwards. If your tent is too far gone, it may be time to invest in a new one—browse our selection of tents and awnings for high-quality, durable options.