How to Prevent and Remove Mold from Storage Unit
A storage unit is meant to be a safe, secure space for your furniture, books, clothing, and other personal belongings. However, if mold begins to grow, it can cause serious damage, leading to costly losses and even ruining irreplaceable sentimental items.
While mold in storage units isn’t extremely common, it happens more often than many people realize. Learning how to prevent mold growth and properly store your items can help protect your valuables and avoid expensive restoration or replacement costs.
Is Mold Common in Storage Units?
Mold in storage units is not always expected, but it happens more often than you might think. A quick online search will reveal many cases where people have returned to their storage units only to find their belongings covered in mold.
Since mold thrives in moist, enclosed spaces, storage units—especially those without climate control—can become breeding grounds for mold if conditions are right.
What Causes Mold Growth in Storage Units?
Several factors contribute to mold infestations in storage units. Here are the most common causes:
1. High Humidity and Moisture Buildup
Moisture is the number one cause of mold growth indoors. Mold only needs two things to survive:
- Moisture (from humidity, leaks, or damp items)
- An organic food source (like wood, paper, or fabric)
If your storage unit has high humidity levels, mold growth is almost inevitable.
2. Improper Storage of Items
Many renters unknowingly use the wrong storage materials, increasing the risk of mold. For example:
- Cardboard boxes work well for dry items but don’t protect clothing, shoes, or fabric-based items from moisture.
- Plastic containers with airtight lids provide better protection against mold and pests.
Tip: Store items a few inches away from the walls and leave space between boxes to improve air circulation.
How to Remove Mold from a Storage Unit
If you discover mold in your storage unit, it is important to act quickly. Here’s what you should do:
1. Identify the Source of Moisture
Mold cannot grow without moisture. Before removing the mold, find the source of the problem and fix it.
- Check for leaks in the ceiling, walls, or floor.
- Look for signs of high humidity or condensation.
- If possible, use a dehumidifier to remove excess moisture.
2. Clean the Mold Safely
Before starting, wear protective gear, including gloves, goggles, and a face mask, to prevent exposure to mold spores.
Here’s the Step-by-step mold removal process:
- Dampen the affected area with a wet cloth to prevent mold spores from becoming airborne.
- Use a scrub brush and mild detergent to remove visible mold.
- Apply a solution of 1.5 cups of bleach per gallon of water and let it sit for 15 minutes.
- Rinse thoroughly and allow the area to dry completely.
- Use a fan or dehumidifier to remove any lingering moisture.
How to Prevent Mold Growth in Your Storage Unit
Preventing mold is far easier and cheaper than dealing with an infestation. Follow these best practices to keep your belongings safe:
- Store Items Off the Ground: Moisture from the floor can seep into your belongings, leading to mold growth. Use wooden pallets or shelving units to keep items elevated and avoid storing fabric-based items directly on the ground.
- Ensure All Items Are Completely Dry Before Storing: Even slightly damp items can spread moisture inside a storage unit. Let items air-dry in the sun before storing them and wipe down furniture, appliances, and boxes before moving them in.
- Control Humidity Levels: Mold thrives in high-humidity environments. Keep humidity levels between 30%-50% to prevent mold, use a humidity gauge to monitor conditions, and consider renting a climate-controlled storage unit for added protection.
- Inspect the Storage Unit for Mold Before Moving In: Before signing a storage contract, check for visible mold growth on walls and floors, look for water stains, leaks, or musty odors, and ask for a different unit if you notice any red flags.
- Use Moisture-Absorbing Products: The right materials can help keep humidity levels low inside your storage unit. Silica gel packets absorb excess moisture, charcoal bags help control humidity and eliminate odors, and dehumidifiers (if allowed) can further reduce moisture levels.
Can Mold Grow in a Climate-Controlled Storage Unit?
A climate-controlled storage unit significantly reduces the risk of mold but does not eliminate it completely. If damp items are placed inside, or if there is an unnoticed leak, mold can still develop. To maximize protection, follow all standard mold prevention practices, even in climate-controlled spaces.
If you discover mold in your storage unit, it’s important to act quickly. Professional restoration experts specialize in mold removal and can assess the extent of the damage, identify the moisture source, and use advanced cleaning techniques to eliminate mold safely. They can also treat affected surfaces with antimicrobial solutions to prevent future growth and, in some cases, restore salvageable items that have been contaminated. If mold is spreading or causing damage, don’t wait—call a mold remediation specialist immediately to protect your belongings and prevent further deterioration.
About Vince Sandri
Vince Sandri is a content writer and blogger with more than 12 years of experience. His expertise is in creating content related to disaster restoration, including information about preventing and reacting to natural disasters like flooding, water damage, fire and smoke damage, mold growth, storm damage and more.
Vince has been the main contributor to RestorationMasterFinder.com since 2014. Over that time, he has written numerous service pages and blogs for disaster restoration providers featured on RestorationMasterFinder.com. Vince has done extensive research and covered a wide range of topics relating to disaster restoration to help homeowners, business owners, and property managers better protect their property. He understands the problems that disasters like flooding, fire, smoke, and mold can cause as well as the best ways to respond to these issues to limit the damage.
Vince completed his Bachelor of Arts degree at Aurora University and his master’s degree at DePaul University. He has been writing SEO website pages, blogs, and press releases since 2012. Vince is also a musician and can be seen playing in the Chicago, IL area.
