Mold! How to prevent mold in my storage shed?

You purchased an outdoor storage building to store the things you value. Whether lawn equipment, woodworking tools, or family heirlooms, you want your things protected from the elements. But sometimes, those elements invade even the best-kept homes and storage buildings, causing problems like mold and mildew. From the construction phase to packing your items, there are several ways to prevent mold in your shed.

Begin with proper storage shed construction.

Your first line of defense when it comes to preventing mold and mildew in your outdoor storage building is ventilation. A ridge vent in the shed’s roof and gable vents allow hot air to escape without allowing rain to enter.

Another place to install vents is in the soffit under the eaves of the building. Soffit vents draw cooler, drier air into the building, pushing the warmer, moist air out.

Vapor barriers help to prevent moisture in storage buildings, too. A polyethylene plastic or foil placed on the walls and beneath the floor blocks moisture from outside.

If you are shopping for a new shed, ask your storage shed representative if the product comes equipped with these features. If you already own a backyard shed without them, you can install them yourself, or keep a window opened slightly. You can purchase the necessary vents and vapor barrier material at most hardware stores.

Regulate the humidity levels.

For ideal health and comfort, maintain a relative humidity level in your home between 30-50 percent, depending on the time of year. This level of humidity is also necessary to prevent mold and mildew—whether in the house or in the outdoor storage building. Installing a hygrometer will allow you to keep an eye on the relative humidity levels so that you know when to take action.

Run a dehumidifier. If your shed is wired, running a dehumidifier in your outdoor shed will keep the humidity at optimum levels, therefore preventing mold and mildew. Remember to empty the water tank on the dehumidifier twice each day, or as needed.

Keep the air moving. Run a fan on low to keep the air moving in your outdoor storage building.

Use desiccants. A desiccant is a substance that draws moisture to itself. You can buy commercial desiccants, like Damp-Rid. Other things to try are dishes of charcoal briquets or cat litter.

Practice smart packing techniques.

Before stashing anything in your shed, make sure it is absolutely free of moisture. Damp umbrellas or hammocks, bikes that have not been dried, and swimming or boating equipment are notorious for molding once put away wet, in the dark, and forgotten.

Also, avoid stacking boxes of things along the exterior walls. Leave a gap of several inches to promote air flow. The more air circulation you have, the less moisture will hang around.

Remember routine storage shed maintenance

According to Mike Delaney of SERVPRO, routine maintenance is a key factor in preventing mold and mildew from occuring. Painting the storage shed with a high-quality exterior latex like Sherwin Williams Duration® will provide a mildew-resistant coating. Delaney also recommends checking the shingles on a regular basis.

“Moss on shingles,” he said, “is due to moisture and lack of direct sun exposure.” To solve this issue, trim nearby trees and shrubs to allow sunlight on the roof.

Moisture under the building also is a contributing factor. “The unit should be off the ground with air flow underneath,” he said. Of course, regular mowing and weed eating up next to the building is essential.

Finally, regularly check your storage sheds for leaks. Check the doors and windows, including the thresholds and door sweeps. Also, check the roof for signs of leaking. Use caulk where necessary.

If you’ve run through this checklist and still have mold issues in your building, contact your nearest Ulrich Lifestyle storage shed representative for help.

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