Metal building condensation

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RustyRatRod

I was born on a Monday. Not last Monday.
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What can I do in the RIGHT NOW that's cheap or NO COST to help with condensation with my metal building? I am going to end up losing some valuable parts and engines due to rust. I have a 24 x 28 x 12 metal building on a concrete slab. I have not had problems like this except in the past few recent years. I need to know what I can do NOW to help combat it, or I may as well just cart it all off to the scrap yard.
 
Keep it closed up, I have noticed it more at my place this year with the screwey weather if I am out working with the door open. I had to run my big barrel fan to dry the floor after I closed it all back up after a few hours. 30's to 70's and everything in between... All depends on what the humidity is. Only low cost things I have seen help are crib things up off the concrete and put down a good vapor barrier, can get it at any home improvement store in a big roll. I have done it before when storing dirtbikes for winter, would prevent condensation from building up in the crankcase and "milking" the oil up over the winter. I just cut out a section big enough to cover where I was parking the bikes and duct taped it down.
 
Or finish it and make it more airtight, but you already know that - not low cost...
 
I assume you have no insulation on the walls or underside of the roof. Are you getting condensation on the underside of the metal roof, and then it drips down?
 
I have this issue in my garage if I open the doors on a very humid or rainy day. I just had this happen yesterday, not thinking, I opened the garage door and with in minutes the intake manifold on my engine was dripping from condensation, the floor was soaked and I was not too happy. I will just keep the doors closed when it is that humid out.
 
No insulation. I am getting condensation on everything. Whether it's covered or not. Even on the tools closed up in my tool boxes. Everything I have read says not to insulate the ceiling but only the walls and to coat the floor. All of that is out of my reach right now. I could cut some gable vents. But I don't really know how much that would help.
 
You need to remove the interior moisture and/or provide some level of insulation for the interior metal structure surfaces to provide a temperature gradient to prevent the condensation from occurring on the surface of the metal structure.

Spraying the interior surface with a rubberized paint will help reduce the surface condensation by raising the temperature of the surface contact but a good high volume dehumidifier will fix the issue no matter what the temperature differential is.

Moisture from air only condenses when the surface it contacts is below the dew point temperature. Lower the dew point temperature of the air below the contact surface temperature and it will never condense.
 
I looked a dehumidifiers on the Lowes site. They aint cheap but that might be the best bet for now.
 
No insulation. I am getting condensation on everything. Whether it's covered or not. Even on the tools closed up in my tool boxes. Everything I have read says not to insulate the ceiling but only the walls and to coat the floor. All of that is out of my reach right now. I could cut some gable vents. But I don't really know how much that would help.

That means that you need to keep everything in the garage at or above the outside temperature so that condensation won't occur. More vents won't help.

The issue is that the surfaces are below the dew point temperature of the air they are exposed to.

Two wrenches sitting on the counter. Put one in the freezer overnight and when you bring it out into the room you can watch the surface become covered with the water that is condensing from the air...but the wrench left at room temperature remains dry.
 
All the scientific hooha is appreciated but won't help my stupid *** a bit. lol


....and I am not arguing as this is something I know nothing about, but everything I have read says vents will help.
 
All the scientific hooha is appreciated but won't help my stupid *** a bit. lol


....and I am not arguing as this is something I know nothing about, but everything I have read says vents will help.

LOL! Ok, I'll make it simple...just keep everything inside warmer than the outside at all times and no condensation will ever happen.

Vents won't help prevent it...they will only make it worse. They only help dry it out after the condensation has happened.
 
Now that makes sense. Thanks.
 
Rob the only way I'd know "cheap" to cure this is to get some big plastic bags, the best, thickest you can afford, and pack as much stuff (parts, tools) in them as you can, then use your vacuum to get as much air out of them as possible, and seal 'em.

Oil anything and everything can.

Just about any oil, if you have access to crank drainings use that

That is one reason I'm always "railing" at these guys who want to use salamander / unvented etc gas / lp and kero heaters.......they just pump more moisture into the shop.

The only long term answer is the proper vapor barrier and insulation.

If you can box the smaller stuff up and bag it and carry some of the parts into the house somewhere.

You probably know by now, I have no shop. I've thought about getting some plastic barrels with removable lids, packing them with "stuff" and then pumping them full of CO2. Sealed with a bunch of dessicant would work, that costs money, too

Insulation in warm climates / high humidity are much different "up here" where the primary "thing" is hot and dry, or cold and either dry or wet. "Down there" you can get into cooler inside, hot outside, with a high dew point. This means that even (improperly) insulated / vapor barrier, you can have moisture problems in a building in high humidity conditions.
 
Well, I guess I can buy like a small piece a payday and sooner or later I will have it done. BUT, in the meantime, I have a leakin roof on the dang house I have to deal with after all this rain. I have a really bad spot on the roof above the back porch and a smaller leak in the spare bedroom right on top of a window. Oh happy day.
 
Yup. All this works exactly like a cold beer. The beer can is the inside walls of your shop, and it also represents the tools in your shop. The place you are in with the beer represents the inside air of your shop.

The warm air in your shop is humid, and it condenses on the cold walls of the shop (beer can) as well as the cold tools / parts (beer can)

I think down there you would need a double vapor barrier (inside and out) to do things right.

Not insulating the ceiling would be a mistake.
 
never tired this but some one once told me string up a cord with a couple light bulb sockets the heat from the bulbs will keep it dry like i said i never tried it
 
never tired this but some one once told me string up a cord with a couple light bulb sockets the heat from the bulbs will keep it dry like i said i never tried it

my metal de-tached garage used to do the same thing. finally insulated it and put a metal ceiling in it , creating an enclosed attic (non acessable). stopped about 98% (guessing). only time I get sweat on the stuff inside are extreme circumstances in weather changes, or heating it up too warm too fast. the foam board type insulation is cheap and works pretty well if you seal the seams. the thicker the better tho, and the foil faced is way better than non foil faced, but a lot higher,=$
 
I guess that's why your ID is RustyRatRod - sorry I had to do that hope you get it figured out isn't home ownership great
 
We had the same problem after we built out metal pole building/garage. It would be raining inside from the moisture. We cut foam insulation between the studs( including the roof) problem solved. 25 years later...still holding up great.
 
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