New garage, condensation???

[Jimbo306]

Stood a detached 24x24 garage with 10’ ceilings this past fall; with the help of some buddies and my father in law it is now wired/insulated/poly’d & boarded.
Began mudding & taping and have now noticed that I have condensation / small puddles in the four corners of my garage.
I had been running a 2800W electric heater throughout the process and has only been recently been left on constantly once poly was hung. Have not had this issue until this week.
I have a dehumidifie running day/night and does not seem to be helping too much with the water in the corners.

 

[porschen]

You sure it isn't water coming in from somewhere? Is it running down the walls?

Does your floor have a vapor barrier?

 

[Jimbo306]

The garage is fully boarded. The sheets do not feel wet, and I have second coat of mud on.
I had brought in the dehumidifier in to help with the moisture assuming it was from the mud going on the walls.
No vapour barrier under slab to my knowledge.

 

[porschen]

Unfortunately you'll probably be fighting an uphill battle if it is coming through the floor (if you don't have a vapor barrier under the concrete). You should be able to tell if it is coming through the floor by putting a 2ftx2ft piece of plastic for a day and see if it is wet underneath.

 

[theoldwizard1]

What is the outside humidity in your area ? Much of it could just be the normal condensation of the air. If you did not install a vapor barrier under the concrete, thta is certainly a source.

Keep up with the electric heat. Any other not vented heat source, especially propane, will just ADD moisture.

 

[n20junkie]

People don’t understand the vapor barrier need until they start using their shop.

I had a friend who had a steel building put up and the pad lacked vapor barrier. It always had a smell and the humidity was WAY higher than a hangar should of had.

 

[Jimbo306]

Had some extra fans in garage over night, along with humidifier (which had to be emptied)
Second coat of mud is now dry, and 3/4 corners that had moisture are now dry with the fourth drying.
Possibility of the moisture coming from the raised level of humidity from drywall mud? The humidifier would go from 30 to 45 within half hour of mud being applied.

 

[n20junkie]

The mud is putting some humidity into a room. Latex paint does the same thing. I’ve made the mistake of painting a room with latex and then shutting the door. Humidity goes to a out 80 pecent when you do that one.

Only time will tell where your issue truely lies.

 

[ConCretin]

I don't think the lack of an under slab vapor barrier is your main issue. The amount of water vapor making its way through your slab is probably insignificant compared to all the drywall mud. The moisture in the warm air is probably condensing when it comes in contact with the cool concrete slab. I suspect the problem will go away on it's own - at least until the next humid spring day.

 

[PeteyDaMan]

I was having the exact same issue when they were mudding my garage. They left a heater going to keep the temp up and I was seeing puddles on the floor, mostly near the doors (where I suspect some air infiltration). After a day or 2 of drying, it all went away.