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Dehumidifer in my garage

I have a 500 sq ft non heated garage that I store 2 classic cars in. I was thinking about getting a dehumidifier and placing in the garage to keep the moisture down in hopes of preventing rust on my cars. What do you think???

If your climate is anything like, mine, I think your money would be better spent on some gas to enjoy your classics a little more.

In order for the dehumidifier to work efficiently, the garage would need to be sealed very tightly.
If your garage is like most, the garage doors do not provide a tight seal on their side edges, and this would serve to freely admit moisture from the outside.

To see if this is the case with your garage, go into the garage during the day, and turn out the lights. If you can see light around the edges of the garage door, then it is as poorly sealed as I suspect.

Most likely, a dehumidifier would run continuously in this type of situation. simply because you would be–in effect–attempting to dehumidify the great outdoors. The electrical bill would likely be incredibly high, and in spite of the cost, the humidity in the garage would be almost as high as it is outside.

Concrete Floor? How About Parking On A 4-6 Mil (.004"-.006") Plastic Sheet Vapor Barrier?

Sometimes concrete is poured over a vapor barrier. If not, how about a vapor barrier above the concrete, beneath your classics? Epoxy paints are another consideration.

Testing your floor . . .Some folks duct tape a large sheet of plastic down to the concrete to see if moisture forms underneath. Differing weather conditions can trigger different results.

If your garage doesn’t let the rain in, it should be good enough for any two lifetimes. I used to park outside in Ca. and had no rust compared to Maine. I can see more corrosion on my brake lines than I had on an entire Ca. car.

What do you think?

Depends on the construction of the garage, and the weather in your area.

Part of the problem is that cities and counties that get significant snow in the winter put salt on the roads. I’m in Minnesota. For this reason, people with classic cars here don’t drive them outdoors in the winter. I imagine this would be true in Maine.

It depends on the construction and condition of the garage and your definition of “classic cars”.

If these are truely valuable classics, and the garage is fairly new and in good shape, then I’d suggest a floor covering (there are various “systems” available). If it’s woodframed, I’d also recommend insulation, a vapor barrier, and firewall sheetrock. If it’s concrete you could seal it with any number of sealers. I like epoxy-based paint. Bathtub refinishing paint is epoxy-based.

You may even want to put in a fire suppression system.

So, what year and kind of cars are we talking, and what kind of garage?

What is the RH like in your garage typically?

t depends on the construction and condition of the garage and your definition of “classic cars”.

And I would add the climate where you are.

Joseph made an excellent point about the climate.

Jay Leno bought a Deusenburg that was stored in an unattached garage in southern California for over 50 years with a broken camshaft. While it did need some work, and the engine was rebuilt, the body and chassis was in great shape and the car was brought back to roadworthyness with minimal work on either. Even the interior needed no restoration, and still has the original upholstery.

There’s a one hour special on this car that occasionally airs on PBS. Posters to this thread would, I’m sure, enjoy it.

Leno’s collection is also featured on My Classic Car from time to time. Last week Dennis and Jay took Jay’s new Ariel Atom for a spin. It has an internal combustion engine (not electric), in case you are interested.

I saw that show a couple of times…EXCELLENT.

I liked the part about when he was explaining about the valves being adjusted. It was a 40 hour job…JUST TO ADJUST THE VALVES. Also liked the little spoof they played at the end.

Wouldn’t even attempt it unless the garage is decently insulated with a vapor barrier. If it’s like mine…just open studs it’ll run and run and run…but it’ll never pull all the moisture out of the air. It’s also NOT needed during the winter months if temps drop below 60.