It is usually a good idea to put your items in climate-controlled storage if you can afford to do so. The problem is not so much the temperatures they may experience in a non-climate-controlled unit, but rather the humidity and the fluctuations in humidity. A climate-controlled storage unit keeps humidity levels low and constant, so you don't have so much trouble with mold growth and other moisture-related issues.

But what should you do if you cannot afford climate-controlled storage or there are no facilities in your area that offer it? There are a few things you can do to protect your items in spite of high humidity and fluctuations in humidity.

Don't Wrap Too Tightly

When covering your furniture and appliances, be careful not to wrap them too tightly. You want them to be able to breathe so that if moist air gets trapped against them, it has a way to escape. When possible, use breathable materials like cotton sheets to cover your items rather than tightly covering them in plastic.

This is especially important when it comes to leather goods. Wrapping them in plastic will generally result in mold growth.

Use Tote Boxes With Air Holes

Cardboard boxes are not the ideal choice in a non-climate-controlled storage unit. They may absorb moisture when the humidity rises, and then hold that moisture against your items even when the humidity drops. Plastic tote boxes can be a good alternative, but only if they have some holes that allow them to breath. If you cannot find storage totes with built-in holes, you can create a few breathing holes in them yourself by heating up a screwdriver in a candle and then pushing it through the plastic to melt it.

Leave Space Between Boxes and Items

You may be tempted to pack as much as you can into a little storage unit. However, you are better off opting for a larger storage unit so you can leave more space between your boxes and items. This allows air to circulate over them, removing moisture when the air is dryer. You can stack boxes, but leave some space between the stacks. Try to alternate between items that might be damaged by moisture and those that won't. This will help the moisture-prone items dry out faster if they do get a bit moist during a humid period.

Store Items Off the Ground

Storing items on the ground can cause a few problems when it's humid. For one, the flooring materials, like concrete, may "sweat" when the temperature and humidity levels change rapidly. Also, any moisture that beads up on items may drip down onto the floor. Your items may then wick it up from the floor, causing damage to the bottoms of those items. Lay some pallets or a platform down on the floor and store all of your items on top of it.

Put some desiccant in the corner.

You can purchase containers of desiccant at most hardware stores. They contain a silicone material that is meant to absorb moisture from the air. If you place a couple of them in the corners of your storage unit, they will help buffer some of the fluctuations in humidity. Just make sure you replace your desiccant containers every couple of weeks since they stop absorbing moisture once they become saturated.

While your best choice is usually to rent a climate-controlled storage unit, there are some times when that's just not feasible. Follow the protective tips above, and you'll reduce the chances of finding moldy, moist, or otherwise damaged items when you open up the storage unit again.