How much Humidity is too much for a car??? -- HELP!!

[miamivice]

I know high humidity isn't good for a car (& I have heard a little bit is actually ok to prevent all the rubber/fabric parts from drying up)....however, I dont know how much is too much.

I keep my 69 charger in my basement garage and it is pretty humid.   I keep the car parked in an Air Chamber http://www.airchamber-carcapsule.com/
Nonetheless, it is humid...I could really feel it yesterday (and I am not sure why all of a sudden it seemed to have gotten humider).   I have a dehumidifier I used to use in my old house, I plugged it in last night and come home today after work and the whole resivour was full....unsure of the size, guessing it is a 30 - 45 pint reservour.

Is this really bad for my car?  The last thing I want is my car to get destroyed by where I keep it after I just got done restoring it...

[JB400]

If Seattle is anything like Missouri, you've probably cooled off some.  Cooler temps allows air to condense and so does the moisture in the air.  Another thing that increases humidity is water.  Has it rained lately, or do you have any water leaks?  I don't have an exact number, but if you have mold growing in the garage, that is definately too much.

[68X426]

Probably anything over 40 percent is unhealthy for a 60s car. And most of the country is over 40 most of the time. A quick internet search said that Seattle averages 70 annually, with low monthly average at 61 and high at 81. That's why you guys are the Emerald City.

A basement garage may not have a vapor barrier in place between the walls and the ground outside. Or a poor one at best. Environmental changes (storms, sunny, just plain weather) help "push" moisture into the garage every day. Besides the possibilities of ground water, poor drainage, a plumbing leak or rain runoff, if there is no actually ground-to-wall contact.

You mentioned "your old house", so this a new residence for you. Any idea how it was built? If you own it, get a contractor to evaluate and fix as needed.  http://en.wikipedia.org/wiki/Vapor_barrier

If you rent, then all you can do is dehumidify 24 hours a day.

One of Seattle's finest:

[XS29LA47V21]

Honestly you may not want to hear it but if you are X miles from ocean with prevailing wind you are doomed.   I grew up on Miami area and bought a 69 in 1984 and it was as rusty as a pasture field builder car now out here.  The place a car lives is a big deal to it's longevity IMO.  The car I just bought out of Central FLA last yr although a great garage kept car has surface rust in areas that do not rust in other parts of the county and I think in that case it was the humidity.  Frankly, I am just jealous you have warm weather, nice beaches and a reason to have a fast boat....

FWIW, I would be careful where you take and spend time.  My sister bought new, garaged kept a long door 1980 checker super straight no rust car almost 20 yrs until late 1990s where they rented a beach house for two yrs, I almost bought it from but she was saying it was rusty and I could not imagine how, she sent me photos where you could put your hand through holes in sail panel and quarter areas.  Be mindfull just like the northern guys keep theirs away from salt/winter and other weather exposure is my ten cents.

[Aero426]

My outside detached garage in Wisconsin typically runs from 40 to 60 percent.   I have a cheap digital thermometer that also reads humidity, so I can monitor it. 

If you can see dampness on the car or floor, it's too wet.   Otherwise, given your location, not much you can do.     You can run the dehumidifier, but depending on the size of the space, you'll see a bump in your electric bill.   We have basements here in Wisconsin, and use dehumidifiers in the summer.      You can set the dehumidifier to knock the edge off, but that it will not run all the time.    If there is a floor drain, you can rig up a hose from the dehumidifier so you don't have to empty the reservoir.   

[1969chargerrtse]

I know high humidity isn't good for a car (& I have heard a little bit is actually ok to prevent all the rubber/fabric parts from drying up)....however, I dont know how much is too much.

I keep my 69 charger in my basement garage and it is pretty humid.   I keep the car parked in an Air Chamber http://www.airchamber-carcapsule.com/
Nonetheless, it is humid...I could really feel it yesterday (and I am not sure why all of a sudden it seemed to have gotten humider).   I have a dehumidifier I used to use in my old house, I plugged it in last night and come home today after work and the whole resivour was full....unsure of the size, guessing it is a 30 - 45 pint reservour.

Is this really bad for my car?  The last thing I want is my car to get destroyed by where I keep it after I just got done restoring it...

Most know I have an Airchamber also.  I have had humidity so thick in my garage that you could write your name in water on the side of the AC.  As long as those fans are moving the air you should be good.  Something about moving air prevents the humidity from doing harm.


http://www.dodgecharger.com/forum/index.php/topic,53994.msg675271/topicseen.html#msg675271

[440]

What about also leaving the windows cracked slightly so air can circulate and not build a difference in humidity which can cause condensation to form.

[RallyeMike]

Sorry to say, that unless you have some sort of water problem at your foundation the only way to control normal humidity in Seattle is to insulate, seal up, and heat your garage. There is just too much humidity in the air to battle.

The garage attached to my house has no heat, but it does have the water heater and furnace inside it. There are no humidity problems because of the heat loss from these mechanical systems. Its not that it's warm and cozy, but there is enough heat to keep things dry. So you don't have to heat it like your house and go bankrupt, just enough to dry it.

The shop in the yard is unheated and even though it is sealed up and dry, slab on grade (not underground), things still slowly develop surface rust and interiors get mold spots. Short of heating it, I have found that constantly running a couple of heat lamps in the fall and winter keep things mostly at bay. This year I plan on running the lamps under each car to see if it improves things even more. 

Good to here from you.