How to Prevent Mold and Mildew in Stored Clothing, Furniture and Decor

One of the simplest ways to reduce the risk of mold and mildew is to make sure you aren’t introducing extra moisture (or the dirt and residue mold can feed on) in the first place.

Before packing, clean each item according to its material and give it plenty of time to dry:

• Clothing and linens: Wash and thoroughly dry clothes, bedding, towels and other washable textiles. Don’t pack anything that still feels slightly damp, and avoid putting warm laundry directly from the dryer into a sealed container. Let it cool first so you don’t trap residual moisture.

• Upholstered furniture: Vacuum sofas, chairs and cushions, paying attention to seams and the areas beneath removable cushions. If you shampoo or steam-clean upholstery before storage, allow it to dry completely — including the padding underneath the surface fabric. Learn more about storing furniture.

• Rugs: Vacuum rugs before rolling them for storage. If you wash or professionally clean one, make sure the backing and inner fibers are completely dry before rolling it up.

• Wood furniture: Clean wood using a product appropriate for its finish, then let the surface dry before covering or storing it. Pay attention to drawers, joints and undersides, where moisture may be less obvious.

• Seasonal decor: Clean off dust and dirt before packing decorations away. Outdoor decor needs particular attention: planters, wreaths, cushions and other items exposed to rain or morning dew may hold moisture even when the surface appears dry. Learn more about storing seasonal belongings throughout the year.

If you’ve wet-cleaned a rug, sofa or other thick, porous item, don’t schedule the cleaning for the morning you move it into storage. Give it extra drying time — ideally at least a full day or as recommended for the material and cleaning method. It’s much easier to wait another day at home than discover a musty sofa months later.

It might seem like sealing everything in plastic would offer the best protection from moisture, but that isn’t always the case. If an item contains even a small amount of moisture, wrapping it tightly in plastic can trap that moisture inside.

The right choice depends largely on what you’re storing:

Plastic can still be useful for protecting furniture from dirt and rain during the move. Once furniture is inside the storage unit, however, breathable covers are generally a better choice for long-term protection.

And remember that the container can introduce moisture, too. If you wash out a plastic tote before packing it, dry the corners, grooves and underside of the lid completely before adding your belongings.

How you arrange your storage unit matters, too. Packing everything as tightly as possible may save a few inches, but it can also reduce airflow around your belongings and make it harder to notice moisture problems.

Instead, organize the unit so you can access and inspect your belongings:

• Leave small gaps around large items. Avoid pressing upholstered furniture, mattresses or stacks of boxes tightly against one another when you have enough room to leave some breathing space.

• Use shelving when possible. Shelves keep smaller boxes organized, prevent you from building unstable floor-to-ceiling stacks and make individual containers easier to inspect.

• Keep vulnerable items off the floor. Shelving or pallets can add another layer of protection for boxes, textiles and other moisture-sensitive belongings.

• Create an aisle. Leave yourself enough room to reach the back of the unit without unloading everything in front of it. This makes occasional inspections much easier.

• Avoid overstuffing furniture. It can be tempting to fill drawers, cabinets and wardrobes with extra belongings, but don't pack them so tightly that textiles and other porous items are compressed together for months at a time.

Tip: Think of your storage unit as a small room rather than one giant moving box. A little extra space and organization makes it much easier to check your belongings and catch a potential moisture problem early.

If you’re storing belongings that are particularly sensitive to moisture, pay close attention to how a storage facility describes its units. Climate-controlled, temperature-controlled, heated and air-cooled storage don't necessarily mean the same thing.

The exact definitions and systems used can vary by facility, but the most important distinction is whether the storage environment manages temperature alone or both temperature and humidity.

• Climate-controlled storage: Controls temperature and humidity. Best for belongings that are sensitive to temperature and moisture. Learn more about climate-controlled storage.

• Temperature-controlled storage: Controls temperature only. Best for belongings that are primarily sensitive to extreme heat or cold only.

Why does the distinction matter for mold and mildew? Temperature and humidity are related, but they aren’t the same thing. Cooling a storage space can reduce extreme heat without necessarily keeping its relative humidity within a particular range. Likewise, heating a space during cold weather doesn't automatically mean humidity is actively controlled.

For moisture-sensitive belongings — including upholstered or wood furniture, leather, clothing, books, photographs and certain artwork — a storage environment that manages humidity as well as temperature may offer an added layer of protection, especially during long-term storage or in humid climates.

Tip: Think about how long you’re storing something, too. A few weeks and a year are very different storage situations. For long-term storage, valuable, sentimental or difficult-to-replace belongings may benefit from a more stable environment.

Once your belongings are packed away, don’t completely forget about them until move-out day. If you’re storing items for several months or longer, occasional check-ins give you a chance to catch a moisture problem before it affects more of your belongings.

When you visit your storage unit:

• Use your nose. A persistent musty or earthy smell can be an early sign that something needs attention.

• Look for condensation or moisture. Check containers, furniture and other surfaces for dampness, water droplets or discoloration.

• Inspect less-visible areas. Look behind and underneath furniture and check boxes or bins toward the back of the unit.

• Pay attention to textiles. Cushions, clothing, rugs and other porous materials shouldn't feel damp or unusually clammy.

• Act quickly if you find water. If you notice a leak, standing water or another facility-related moisture issue, contact the facility manager promptly and move affected belongings away from the moisture when it is safe to do so.

Moisture absorbers can be useful in some storage situations, but don’t treat them as a fix for an underlying problem. They can’t make a damp sofa dry, repair a leak or turn a humid storage environment into a humidity-controlled one.

Before you close and lock your storage unit, do one final check. A few extra minutes now can help you avoid opening the door to an unpleasant surprise months later.

• Clean clothing, furniture, rugs and decor before storing them.
• Make sure every item is completely dry.
• Use sealed containers for appropriate clean, dry belongings.
• Use breathable covers for upholstered and wood furniture.
• Avoid leaving furniture tightly wrapped in plastic for long-term storage.
• Leave some room between large items rather than packing everything tightly together.
• Keep moisture-sensitive belongings elevated when appropriate.
• Leave an aisle so you can inspect the unit later.
• Know whether your unit manages temperature, humidity or both.
• Plan occasional check-ins during long-term storage.

The big rule to remember is simple: don’t pack moisture in, don’t trap it around your belongings and don’t assume temperature control automatically means humidity control. Those three habits can go a long way toward keeping clothing, furniture and decor in good condition while they’re stored.

Preventing mold and mildew starts well before you lock your storage unit. Clean and dry your belongings thoroughly, choose storage containers and covers based on the material and give yourself enough room to periodically inspect what you've stored.

If you’re storing moisture-sensitive belongings, pay particular attention to the type of storage unit you choose — and ask whether temperature, humidity or both are managed. Use our Storage Locator to find a SmartStop facility near you and compare available storage options, or explore the SmartStop blog for more practical advice on protecting and organizing your belongings.

Can clothes get moldy in a storage unit?

Yes. Clothing can develop mold or mildew when it is stored damp or exposed to excess moisture. Always wash and completely dry clothing before storage, and choose an appropriate container or breathable garment bag based on the fabric and length of storage.

Should I store clothes in plastic bins or breathable bags?

Plastic bins work well for many clean, completely dry everyday clothes and linens. Breathable garment bags may be a better option for hanging garments, delicate pieces and certain natural fibers. Avoid storing clothing long-term in thin plastic dry-cleaning bags.

Should you cover furniture with plastic in storage?

Plastic can help protect furniture from dirt and rain while you’re moving it, but tightly wrapping upholstered or wood furniture in plastic for long-term storage can trap moisture. Once inside the unit, use a breathable furniture cover or clean cotton sheet when appropriate.

What is the difference between climate-controlled and temperature-controlled storage?

Temperature-controlled storage primarily manages temperature to reduce exposure to extreme heat or cold. Climate-controlled storage may also manage humidity, depending on the facility. Because these terms aren’t necessarily used the same way everywhere, ask the facility whether temperature, humidity or both are actively managed.

Does climate-controlled storage prevent mold?

Climate-controlled storage can help reduce environmental conditions that contribute to mold, particularly when humidity is actively managed, but it can't guarantee that mold will never develop. Items still need to be clean and completely dry before they're stored and packed appropriately.