Grill Cover, trap humidity and cause rust/corrosion?


Bob N

New member
I just purchased a Gensis EP-330. I have no issues with it, but I want to protect it for the future.

Background: I had a competing brand of grill for the past 8 years. This is one of those brands that seems to be carried by every big box retailer. This grill rusted from the inside out. It was "stainless" but that was mostly the external parts. Inside the firebox (itself coated steel) was cast iron grates, heat defusers (flavorizers), flame cross over bars. Beside the cooking/heat distribution deficiencies later learned by myself of this grill, it also started rusting immensely.

The grates were shedding rust, the spot weld tabs holding the defusers rusted off and the defusers partially rested on the burner tubes. The flame cross over ignition bars and the tabs that held them rusted apart.

We covered this grill and often when removing the cover (I believe one of the covers we used before being torn was a Weber cover I picked up on clearance) we would often find moisture on grill surfaces in the form of trapped moisture buildup, condensation.

The grill was stored on a western facing heavily shaded patio under a 3 foot eave (partial shelter from rain). My wife thinks we should not cover it. She thinks that covering the grill will trap moisture that evaporates from the rain moistened patio will shorten the life of the grill.

First, congratulations on the EP-330. Most people are not even aware that the EP models exist, since they are not sold at the big-box stores. The Genesis EP330 would be my choice if I had to buy a new gas grill today.

I too have wondered about the cover issue. I still think that the covers help much more than they hurt. I have four grills in our screen room (wife says that is too many) two are covered and two are uncovered. The covered ones stay much cleaner than the uncovered ones and rust has certainly not been an issue with either of the covered ones.

Welcome to the forum, Bob.
If it's in a covered location there is no need to use a cover. But, yes covers can and do trap some moisture. The best is a canvas cover. My Wolf came with a fitted canvas cover. Works great
The Weber cover for my 2000 vintage Genesis Silver B used to be made with a mesh panel on the front like so:

The current covers are solid vinyl. Never thought much about it. But maybe that panel was there to allow for air circulation and evaporation when the grill was covered. Those vented covers certainly kept my grill in excellent shape for years.

Or maybe the mesh was there to relieve air pressure? So the wind wouldn't get up inside and knock the grill over or blow the cover off?

The panel was located on the front above where the cover went over the handle. So any water going through the mesh would drip straight down onto the ground rather than onto the grill itself. Would be pretty easy to DIY some vent holes in that same spot. Or get a non-Weber branded cover that has vents. They're available on amazon.

If your grill is exposed to any weather at all, my vote is to use a cover.
Last edited:
I guess I'm too lazy to use my covers. That said, I have a Genesis Gold C that has sat outside in the sun, rain, sleet and snow's of Ky for 15+ years and there isn't a spec of rust on it. Can't speak to newer models as I've never had one. My "youngest" Genesis is 11 years old or so.
I've had my Genesis 1000LX covered since I bought it new in 1999 and it has no rust whatsoever anywhere on it. But and there is always a but, it's spent it's whole life in dry climates. We now live in Arizona where rust isn't allowed, anywhere, period.
So if you live in a high humidity area it could be a different story.
But I keep all my grills covered (See signature line) and have had zero issues with all of them.
I've rebuilt 5 Weber gas grills this year from 7 to 20 years old.
Three were over 15.
Grills rust out not from covers trapping humidity but from the use of poor materials.
Weber makes their fireboxs from cast aluminum & lids from porceloin coated steel.
It's the materials not the care.
Thanks for all the feedback.

The aluminum firebox with its ledges (as opposed to spot weld stubs) for the heat defusers and easier clean out via the under tray were a factor in my decision.

The thoughts seem to be mixed on the benefits/threats in regards to rust. Some use a cover, some never. As such, I guess I'll get a cover to keep the tree dander that gets caught in the wind off of the grill's flat surfaces. There is a lot of spruce needles and other organics settling on the surfaces each day at this time of year BTW. I'll just hope that the cover doesn't introduce issues.

Right on the money, Bob. Just like wearing plastic rain gear; moisture can't get out and you stay wet inside. You have to have a cover that will breathe and there are a few ways of doing that but I think that the covers that are not totally waterproof are the best. They will keep the sun, dust and chipmunks off your grill but will allow your grill do dry out quickly. If you have condensation under a heavy vinyl cover then it will just sit there. I have a fabric-y cover on my offset smoker but I do put a tarp on the cover over the winter to keep the cover itself from icing.