voodoo51

What are the ideal conditions (temperature and humidity) for car storage inside garage?

MUSSBERGER

I read 70 degrees and 40-50 relative humidity.

voodoo51

Thank you!

LexVan

That's a lot of humidity. You'd never achieve that in a winter hibernation environment in the Midwest.

C2 Turbo

That's whats needed for the in-doors as well, achievable and maintainable? Though I heard it could go from 45-55% too

idart930

Why such high humidity? There's reason the aircraft boneyard is in Arizona. Wouldn't 30-35 % be better?

Mark Houghton

Humidity in my heated garage (kept around 55*F on the average throughout the winter) is around 20% max...or lower depending on how cold it is outside. I'm in a desert environ, ya' know? Not much chance of condensation happening to worry about corrosion. As far as external rubber stuff, just do a good wash/wax and apply a good protectant prior to the long sleep. Full tank of gas with stabilizer added, good to go next spring.

idart930

20% humidity seems really low...do you de-humidify your garage? Where I am in Colorado, 30-35 % is average in an unheated insulated garage. I've had no issues with humidity with my Porsches and no moisture/rust issues but of course I don't put them away wet. I do treat the interior leather every year but they are also in an amazing state of preservation due to my climate. I have remote temp/humidity sensors in my garages so you can monitor day-to-day. When it rains/snows, humidity can reach up to 40% inside but that is still low with no moisture issues.

Mark Houghton

A fair question. I just checked my weather station: 27*F outside and it's 21/49% humidity outside/inside. I don't have a humidity sensor in my garage but would guess it's probably somewhere in between the outside and inside readings so yeah.....I may have understated the actual that my car's stored in. I'll put a gauge down there and report back.

MUSSBERGER

https://roadscholars.com/storing-collector-cars/

Spyerx

In other words: Coastal southern california :-)

idart930

That's an excellent article but there are several online calculators that suggest that 70 degrees and 50% humidity show a dew point of 50 http://www.dpcalc.org/ indicating that natural aging is at risk with that high of humidity at 70 degrees. If you decrease the humidity to 44% at 70 degrees the dew point is 47 and now okay for natural aging. I wonder what the Porsche White collection has set for temp/humidity?

lee88

30-40% is probably fine for cars, but very low humidity (anything <30%) isn't good for all kinds of non-metallic materials like rubber, leather, certain adhesives, etc. In general low humidity is good for metal at preventing corrosion, though keep in mind the boneyard is mainly focused on preserving the aluminum but not necessarily other materials in those aircraft.

Mark Houghton

As promised, I dug up an old analog gauge and set it on the car in the garage. Note: My home is a split level, with the garage underneath and thus surrounded by three insulated walls and ceiling. With the humidity in the house at 49%, the garage is sitting at around 42%, which should be no surprise since outside it was 21% with nothing but a rollup door as a barrier (well fitting and insulated, but it's a garage door you know?).
I keep the garage heated all winter, usually around 55* to 60* so I suspect the humidity stays rather constant, consistent though lower than the house itself. Again, I''m in a very dry climate but the normal house humidity is what keeps the garage in check. Is it ideal......hell if I know, but it's what I've got.

UberXY