Epoxy floor sweating big time

mscheer772 · Mar 30, 2007

My garage had some hugh cracks in it when we bought our house. I had a cement guy jack hammer the old floor,then had him pour 4inches of cement over the old concrete(with rebar). Floor held up nicely for 4 years, 3years ago I had the floor epoxy coating,that also has held up nicely. Last fall I had the ceiling and walls insulated.This spring after a 40 degree rise in tempature(over a 24 hour period)the floors were sweating big time. Is this something I should address? Would roof vents be worth the effort to put in? Is this a minor inconveniece,or a major problem. The garage is unheated.

Sorry for rambling.

-Mike-

MrJimi · Mar 30, 2007

Mike, I would suggest lots of ventilation, the problem you have is like taking a cold drink out of frig and it sweats. Get some open windows, vents or what ever, I like roof turbines, the ones that spin with the wind they work great and dont use electric
Jim

mudcat · Mar 30, 2007

Ventilation. An exhaust fan controlled by a humi-stat works great.

BobRip · Mar 30, 2007

How often does this happen? Once in 3 years? Why do anything for such a rare event, unless you need a fan for other reasons? It's just caused by the floor temperatue being lower than the dew point. Actaully bringing warm air may cause more condensation untill the concrete warms to above the dew point. IMHO. This warm up probably won't take long.

kmdigital · Mar 30, 2007

In all honesty, ventilation won't help all that much. Keep the garage warmer in the winter and it won't do that. Basically, your concrete is considerably colder than the warm humid weather we had this week, therefore the surface is below the dew point of the air and it will condense on the surface of the concrete just like a glass filled with a cold beverage on a humid day. It will always do this anytime the concrete is below the dewpoint of the air above it, ventilation or not, unless you blow a fan directly across the surface of the concrete to keep the moisture evaporated as fast as it condenses. All the ventilation in the world at the ceiling won't do much good, unless it also warms up the concrete faster than it would otherwise.