10 Things You Should Never Store Near the Water Heater

Storing things near the water heater might seem harmless, but it can lead to fire hazards, moisture damage, or even costly repairs. Whether your heater’s in a closet, garage, or utility room, it needs space—not only to work properly, but to avoid turning into a safety risk. And honestly, some of the stuff people tuck beside it doesn’t belong anywhere near heat or water.

Here’s what you should keep far away from your water heater—even if you’re short on storage.

Paint Cans

Paint and heat don’t mix. When stored near a water heater, paint cans can start to break down or even combust if things get too hot. Even if the can doesn’t explode, you risk the fumes becoming more potent in high temps.

Keep paint in a cool, dry spot where temperature stays fairly stable. If you’re dealing with limited space, prioritize safety—store them in the garage or shed, well away from any heat sources.

Cleaning Chemicals

Bleach, ammonia, and other cleaners can release fumes when heated, and that’s the last thing you want building up around a gas or electric heater. In some cases, it’s not just smelly—it’s dangerous.

These chemicals also tend to corrode nearby surfaces over time. Keep them in cabinets with ventilation or away from heat sources entirely. It’s safer, smarter, and avoids any weird chemical reactions down the line.

Cardboard Boxes

Cardboard is flammable and absorbs moisture like a sponge. Stack it near a water heater, and you’ve set yourself up for fire or mildew—or both.

Even if you’re storing something harmless inside the boxes, the cardboard itself becomes a risk. Use plastic storage bins instead, and make sure there’s at least a couple feet of clearance around the unit.

Propane Tanks

It might seem obvious, but you’d be surprised how many folks tuck a backup tank near the water heater without thinking twice. That’s a huge risk.

Propane is highly flammable, and a leak near any ignition source could end badly. Always store propane tanks outside, in a shaded and ventilated space that’s far from any heat or spark.

Laundry Detergent

Powdered or liquid detergent might not seem like a hazard, but when stored too close to heat, they can break down or leak. Plus, if the cap loosens or the box splits, you could be looking at a sticky mess on a warm surface.

The better move is to store detergent on a shelf or in a cabinet nearby—but not directly next to or above the heater. You don’t want that stuff reacting with moisture or heat unexpectedly.

Flammable Liquids

Anything with “flammable” on the label should be nowhere near a water heater. That includes gasoline, lighter fluid, and some types of adhesives or solvents.

Even small leaks or fumes can catch fire if your heater sparks at the wrong time. It’s not worth the risk. Store those kinds of liquids in approved containers in an outdoor shed or separate area.

Air Fresheners or Aerosol Cans

Aerosol cans are pressurized, which means they can explode when exposed to high heat. That includes air fresheners, bug sprays, and even dry shampoo.

Heat buildup around the water heater can push these cans to their limit—especially in the summer. Store them in a climate-controlled space, ideally out of direct sunlight too.

Curtains or Drapes

Some water heaters are tucked into tight closet spaces where folks try to make things “look nicer” by adding a curtain or fabric panel. That’s a mistake.

Fabric is highly flammable and can easily blow against the heater’s vent or burner. If you’re trying to hide the heater, go with something nonflammable and well-vented—or skip the cover altogether.

Storage Totes Without Lids

Open totes invite dust, moisture, and pests, all of which are more likely to be a problem near your water heater. Not to mention, you’re cluttering up an area that should stay accessible.

If you must store things nearby, use lidded plastic bins, and don’t stack them tight against the unit. Leave space for airflow and access, and check periodically for leaks or heat-related damage.

Old Rags and Towels

A pile of old towels or cleaning rags might seem like a harmless thing to tuck away, but they’re flammable—and they absorb moisture like crazy. Worse, if they’ve been used with chemicals or oils, they could spontaneously combust.

It’s better to keep those in a sealed bin, away from heat and moisture. And if they’re really that old and you’re not using them, go ahead and toss them or repurpose them somewhere safer.

*This article was developed with AI-powered tools and has been carefully reviewed by our editors.