Putting a grill away for the season looks like a two-minute job: wipe it down, throw a cover over it, done. According to Weber’s own “Preparing Your Grill For Storage” guide, that shortcut is exactly how a grill ends up housing mice or growing mold over the winter. And covering isn’t the only decision that matters — what happens to the propane tank sitting next to the grill is a separate question with its own rules, covered here using guidance from the North Carolina Department of Agriculture & Consumer Services’ Standards Division, which administers the state law referencing NFPA 58, the LP-Gas Code.
Why a Dirty Grill Attracts Trouble
Weber’s storage guide is blunt about the cause: “leftover food and grease” left inside a grill over winter create exactly the conditions wildlife and mold both look for. Mice in particular treat an unused grill as ready-made shelter — the lid works as a roof, and any grease or food scraps left on the grates or in the tray becomes a food source. Weber’s fix is the same for gas, electric, and charcoal models: brush the grates and burners clean, scrape the interior surfaces with a putty knife, and push the loosened debris into the grease tray or ash catcher, then actually empty that tray or catcher rather than leaving it in place over winter.
Mold Doesn’t Need Freezing Temperatures to Take Hold
It’s tempting to assume a grill left outside all winter is too cold for anything to grow in it. Weber’s guide complicates that assumption: mold “typically doesn’t grow at temperatures below freezing,” but the milder stretches at the start and end of the cold season — late fall and early spring — sit right in the range mold favors, and it feeds on the same grease and food residue that draws mice. Weber also flags a slower, related problem: grease and food residue trap moisture against metal, and that trapped moisture is what drives corrosion and oxidation over a season of disuse.
If You’re Already Too Late
Weber’s advice for a grill already hosting mice or mold by spring is not to panic. For mold, the guide says to scrape it off any surface it has grown on, then run the grill on high for at least 15 minutes before cooking on it again. For wildlife, the instruction is nearly identical: clean out whatever has been left behind, then run the grill on high for that same 15-minute stretch.
Does the Grill Itself Need to Come Indoors?
No, according to Weber: “Weber grills don’t need to be brought inside for the winter,” though the guide adds that bringing one in “definitely won’t hurt anything” if space allows. For a grill staying outdoors, Weber recommends a cover mainly to keep the exterior surfaces clean rather than as a mold-prevention measure on its own — the cleaning step above is what actually reduces mold risk. A cover with no way for air to move underneath can just as easily trap the same moisture Weber warns about, so cleaning the grill thoroughly and letting it dry before covering matters more than the cover itself.
The Propane Tank Is a Separate Rulebook
Weber’s storage guide contains one firm instruction on this point: “NEVER store a propane tank indoors,” and if the grill has a propane tank, that tank should be left outside even if the grill itself gets moved into a garage or shed. The North Carolina Standards Division’s guidance goes considerably further than that single line, since it’s describing what state law — built on NFPA 58 — actually requires of anyone storing an LP-gas cylinder.
Per that guidance, a stored tank should be kept outdoors, away from heat sources and out of direct sun where possible, standing upright on its foot ring, and in an out-of-the-way spot where it can’t be knocked over, particularly if children are around. The list of what not to do is just as specific: don’t store a tank indoors, under the house or in a crawl space, laying on its side or upside down, near a flame or ignition source, or beside a gas grill that’s currently in use (a spare tank should be kept away from the grill entirely, not tucked underneath it). Older cylinders with only internal, counter-clockwise threaded valves should have a plug screwed into the valve outlet whenever they’re disconnected — but that plug should never go into an Acme-type valve, which has external threads, because a plug there disables a safety feature rather than adding one.
Where the Two Sources Line Up, and Where One Goes Further
Weber and the NC Standards Division agree completely on the rule that matters most: a propane tank never goes indoors, full stop. Where they diverge is depth, not disagreement. Weber’s blog is written for a home cook winterizing a backyard grill and gives that single rule plus a brief note on keeping tanks outside. The Standards Division’s page explains a regulatory standard built on NFPA 58, so it adds detail Weber doesn’t cover, including condition checks worth doing before storage: confirming the valve closes fully, checking that the tank isn’t severely corroded or pitted, and making sure the collar and foot ring are still securely attached. A corroded or pitted tank wall is a weakened wall, and severe corrosion at the collar or foot ring is itself a reason to consider replacing the cylinder.
Keep reading
- Propane Grill Safety: Leak Checks, Storage and Gas Smells
- How to Clean a Grill Safely: Brushes, Bristles and Grease
- RV and Camper Grilling: Propane Safety at the Site
- Grilling on a Balcony or Patio: What’s Allowed