Winter Garage Moisture

Hi Everyone,

I have a 2 stall attached garage, insulated but not heated. In the winter the garage stays warm enough to melt all the slop and snow brought it, however it puddles up from improper slope on the floor. What does make it to the door causes the door to freeze to the floor on occasion. Also the humidity is high due to all the water and I actually get frost on the garage door and door windows.

Is there anything I can do to improve this? Would a powered vent help reduce humidity?

Thanks,
Jeff

Leave a window open a crack to "lose" heat.
Moisture will flow the heat out the window.
If no window, leave the door open just a crack.
1/4 inch is fine.
same principle applies.

Thanks for the advice. Unfortunately all my windows are fixed. Would an exhaust fan work in this case?

I installed one of these for my bathroom and it moves quite a bit of air. I wonder if this would help in the garage.

Panasonic FV-30NLF1 WhisperLine 340 CFM In-Line Fan, 6-Inch Duct

A fan will certainly help with the humidity- if you can get it vented outside. Probably not going to do much for the water that puddles. That will probably require some concrete work. I've heard people using WD40 or silicone spray to keep the door gasket from sticking.

I would control the fan with a thermidistat switch.

I would try it without a fan first.
A fan may remove the warm air too fast.
You want to have it around long enough to absorb the moisture.

If you don’t not have control of the temperature and air exchange rate in the garage .......you have no chance in controlling the humidity. Nature is in control moisture in the garage. On certain days opening the window will help and certain days the open window will only make it ( humidity) worse.

This comes up every year about this time. The topic also has been discussed at length in summer month as well.

Things to remember and learn......humidity is relative to the temperature, that’s why they call relative humidity. Summer moisture in the sealed garage is often more a problem. Summer Prolonged humidity of 70% will cause mold, mildew and rust. Summer the the cold floor will condense moisten on the surface.

The winter snow melt is best pushed out the door daily or use a floor drain. Fan will dry it slightly if there’s not too much moisture (standing water) . Fan will not work on standing water when the humidity levels are high as little or no evaporation is occurring under those conditions . Dehumidifier will NOT work in cold garage temperatures. Plus air exchange rate is working against you and costs a fortune to run.

Add insulation, control the air exchange rate and heat the garage winter moisture will disappear or at least be under control.

Actually Monitor the temperatures and humidity levels over time. Humidity levels in the garage in the Midwest are similar to summer basement humidity problems. Garage with large doors in use and snow melt only adds to the problems and limits the potential solutions.

Example today on them and humidity variations outside to inside the shop/garage.......no sense in opening a door or window:



Paid to condition the air, seal and insulate the garage to avoid swings in temperature and humidity.