Garage Condensation

[69385vette]

I have a 30 x 54 x 12 Morgan building. I have insulated up 8' on the walls with 6' fiberglass batts. There is nothing above the 8' level. The ceiling and eve vents are open to the garage.

In winter, a lot of moisture collects on the floor and the metal surfaces on the frame/engine of the vehicles stored there. Moisture is also heavy on the 4 post lift. This is in the Austin Tx area.

Picture of the inside can be seen here:
https://photos.google.com/album/AF1QipNnflu9F5Dgz3I0kMBmBXMiEzJlsypMsKwzOF1f/photo/AF1QipP617zSnMowoQ_tduq1mJj2W2hFXYYw5yZ4GupA

What do I need to do to prevent this? Is installing a ceiling and HVAC the only option? I am concerned about damage to the vehicles.

Thanks for your suggestions.

 

[rerod]

I have a 30 x 54 x 12 Morgan building. I have insulated up 8' on the walls with 6' fiberglass batts. There is nothing above the 8' level. The ceiling and eve vents are open to the garage.

In winter, a lot of moisture collects on the floor and the metal surfaces on the frame/engine of the vehicles stored there. Moisture is also heavy on the 4 post lift. This is in the Austin Tx area.

Picture of the inside can be seen here:
https://photos.google.com/album/AF1QipNnflu9F5Dgz3I0kMBmBXMiEzJlsypMsKwzOF1f/photo/AF1QipP617zSnMowoQ_tduq1mJj2W2hFXYYw5yZ4GupA

What do I need to do to prevent this? Is installing a ceiling and HVAC the only option? I am concerned about damage to the vehicles.

Thanks for your suggestions.

Its the temperature difference inside to outside, in the cool mornings mostly?. And maybe some moisture coming through the slab if poly wasn't used. You need to insulate the ceiling and don't use poly as you want rapid drying.

 

[Bretny]

Can it be cold in the building and warm outside...then you open the doors to let the warm air in?

 

[Zrexxer]

I've had the same problem here in Pflugerville with my attached garage at my home. We've had temps in the 40's and 50's for days and the concrete was one nice big cold mass. Then in the last two days, we've had fog, rain, and 100% humidity.


I went out in the garage today and about busted my ***, because that saturated 70 degree air condensed on my cold epoxy floor and it's like someone had sprayed a hose in there. Unless you can find a way to equalize temperature and humidity, condensation is gonna happen.

 

[rerod]

I've had the same problem here in Pflugerville with my attached garage at my home. We've had temps in the 40's and 50's for days and the concrete was one nice big cold mass. Then in the last two days, we've had fog, rain, and 100% humidity.


I went out in the garage today and about busted my ***, because that saturated 70 degree air condensed on my cold epoxy floor and it's like someone had sprayed a hose in there. Unless you can find a way to equalize temperature and humidity, condensation is gonna happen.

My dads garage was like that and caused rapid corrosion on everything.

You either need to "equalize temperature and humidity" or insulate.

 

[kbs2244]

Condensation needs still air.
Before you get in too deep try a fan or two

 

[matt_i]

With the building essentially open warm moist air is easy to infiltrate and condense on massive objects that warm up slower and are cold.

Putting in the ceiling and keeping the shop as closed-up as possible will do the most good.

HVAC or dehumidifier is optional, ceiling fan is a cheaper option.

 

[Muckin_Slusher]

Ventilate.

Big vents at opposite ends of the building and let the wind blow through it. I just added vents like this to my warehouse and it made a world of difference.

 

[BB Sig]

Nothing to add but why insulate part of the wall? Why insulate at all if you don't do the whole wall?

Im not dinging you, just curious.

Barry
North Florida

 

[astroracer]

Finish the insulation and put in some type of HVAC system that will maintain the temp. Whether it's cold outside and warm inside or the other way around, moist, humid air will condense on the metal surfaces. The only way to stop it (or keep it to a minimum) is to maintain the temp inside the building and eliminate the temperature fluxuations.
Mark

 

[Showkey]

Finish the insulation and put in some type of HVAC system that will maintain the temp. Whether it's cold outside and warm inside or the other way around, moist, humid air will condense on the metal surfaces. The only way to stop it (or keep it to a minimum) is to maintain the temp inside the building and eliminate the temperature fluxuations.
Mark

^^^^^^^^
This is the answer...........you absolutely must control temperature and humidity.

This is done by insulation and control the building’s air exchange rate.

Fans do not help........moving moist air does nothing except waste money.
Vents do help is the temperature swings and the dew point is reached. Venting just makes you salve to the outside temperature and humidity.

Stopping or controlling Building condensation is the same as stopping an ice tea glass from sweating on warm humid day.

 

[vrinner]

In my recent post on this, someone mentioned “did it happen when you opened the doors” and in the last couple of weeks I didn’t open doors and no issues. Building is heavily insulated so the temp inside is very consistent.

 

[Showkey]

Part of this is condensation problem it shows up on the extreme. Even if the condensation gets controlled it likely the building humidity levels will be far from ideal. ( especially for collector car).

Measure and track the indoor humidity levels, prolonged relative humidity of over 70% will cause bad things to happen. Such as mold, mildew, rust, funky odor so next post why if the headliner in my stored car trashed.

 

[BentBierz]

We have the same problem here in Alvin, TX. When it has been cold outside the slab cools down inside my two buildings that have no climate control. On days where it warms up a little and a breeze is blowing, if I open the doors I end up with a slip-and-slide in the one building that has epoxy floors.

I am getting tired of hand tools and machines rusting and how unbearable it is to work in either building during the summer months so have decided to add climate control to each. Over the past three years I have spray foamed each building. I'm not looking to keep the buildings "residence cool" but to knock down the heat/humidity to a tolerable (and less rusty) level.

 

[sign216]

I had this problem, but because I'm in New England it happens during the non-freezing months. Solved it by putting in a dehumidifier, that runs 24/7 during the Spr, Summer, Fall.

A single medium dehumidifier worked for me, but my shop is small, 14x20'. Perhaps you could put in a larger unit(s), set to drain into the shop's drain (if you have one).

Joe

 

[wssix99]

This happens to just about everyone at some point of the year. Your particular conditions could make things more frequent.

Whenever the floors and contents get cold and warmer, moist air comes in; condensation will form.

This happens a lot when we have cool nights and warm days because the concrete pad and metal vehicle parts will take some time to absorb heat and get to the same temperature as the outside daytime air.

Your insulation scheme (I'm not sure what the intent of partial insulation is, but you should probably re-examine it here.) may enhance this effect by allowing a cooler air to settle in the lower part of the insulated garage (like cold air inside of an open igloo cooler) while the warmer air circulates above that mass between the eve vents.

Vents at floor level would solve this. (You could open and close them when the seasons create this problem for you.) You could also power those vents and get fancy by hooking up differential temperature controls and opening the vents when the conditions inside and outside the garage are in the right state to create condensation. (Presumably, you'd only need to let the cold air in the garage out in the winter when the air outside is warmer.)

 

[69385vette]

All I could do to start. I plan to complete the insulation....

 

[Zrexxer]

In my recent post on this, someone mentioned “did it happen when you opened the doors” and in the last couple of weeks I didn’t open doors and no issues. Building is heavily insulated so the temp inside is very consistent.

That's exactly what happened to me the other day. Things were fine until I decided to take advantage of the warmer weather to do one final oil change on the zero-turn for the year. When I opened the overhead door and let that warm moist air in is when it happened.