Concrete Wall and Moisture

[tdt]

I have been browsing this forum for sometime and have gotten most of my questions answered. I finally have a question that has not been dealt with specifically for my situation. Thanks for your help in advance.

I am in Wisconsin so seasonal changes are pretty significant.

My garage is built into a hill with (3) sides which are poured concrete. I have 2 small windows that have fixed barn sashes in them so I cannot open them. The interior space is about 1400 sq ft.

The Months of May and June are horrible for condensation on the walls and garage floor. I am not sure if this is due to excessive ground moisture, temperature differneces, humidity or all of the above.

The moisture problem is significant enough that some screw drivers I had on my work bench rusted.

I have read other posts discussing concrete floor sealing, but nothing about walls.

Ultimately I would like to install shelves, or a wall system on 1 or 2 of the concrete wall. The system would be used for storage of tools and such.

What are some recommendations for beating the moisture problem, dehumidifyer, air circulation, concrete sealing or installing a mold resistant moisture barrier and putting up the shelving system?

 

[BCM]

What does the outside of your garage look like in terms of gutters, downspouts, and drainage? Gutters should exist, be appropriately sized, and downspouts should empty away from the foundation - ideally tunneled away down hill. Do you have any in-ground / french drains?

Ideally, the outside drainage should be addressed before you consider any of the "inside" remedies you mention above.

 

[tdt]

I just replaced the garage roof with a metal roofing system. The project included replacing existing gutters. Two sides of the roof are pitched and both have 5" gutters over a 30' run. Each carry water away from the foundation at least 10' on a gradual slope.

I thought that would be sufficent.

 

[Will67]

Did you build the garage or was it there when you moved in. From your post it sound like you do not know if there is a moisture barrier in the slab and no weep Tile drainage on the three walls set into hill side?

 

[JerryTX]

I would find out what the source of the moisture is. If its from the soil around the garage (since its built into a hill) then it sounds like the concrete wasn't properly sealed outside. If so the moisture is going to be an ongoing problem which could lead to erosion of the concrete.

If its condensation there are some things you can try. They make a product called "Damp Rid" which is basically pieces of calcium which absorb moisture in the air. I use it in my boats and pantry at home. Its not terrible expensive and might solve some of your problems. You could also try adding a dehumidifier to the garage and see if that helps.

 

[tdt]

Did you build the garage or was it there when you moved in. From your post it sound like you do not know if there is a moisture barrier in the slab and no weep Tile drainage on the three walls set into hill side?

The house was built in 1875 and the garage over a period of time. I am the second owner with no knowledge of how it the concrete was poured. I suspect no external barrier is in place.

 

[tdt]

I would find out what the source of the moisture is. If its from the soil around the garage (since its built into a hill) then it sounds like the concrete wasn't properly sealed outside. If so the moisture is going to be an ongoing problem which could lead to erosion of the concrete.

If its condensation there are some things you can try. They make a product called "Damp Rid" which is basically pieces of calcium which absorb moisture in the air. I use it in my boats and pantry at home. Its not terrible expensive and might solve some of your problems. You could also try adding a dehumidifier to the garage and see if that helps.

I was reading about moisture control on a different thread and they talked about this product. I am not sure if it will work for 1400 sq. foot. I also can not guarantee a tight seal from the outside.

 

[Milton Shaw]

The normal test is to tape a piece of plastic film to the wall if its wet under it then the moisture is coming from the wall, if its wet on the outside then its condensation from difference in temps. Cold walls from winter would sweat until they reached dew point temp so its probably condensation. I know a lot of people have floors sweat and be slick from this. It's something that air circulation or build it out and insulate to keep the cold walls covered are about the only options to keep the moisture under control.

 

[wssix99]

The normal test is to tape a piece of plastic film to the wall if its wet under it then the moisture is coming from the wall, if its wet on the outside then its condensation from difference in temps. Cold walls from winter would sweat until they reached dew point temp so its probably condensation. I know a lot of people have floors sweat and be slick from this. It's something that air circulation or build it out and insulate to keep the cold walls covered are about the only options to keep the moisture under control.

Great idea. You have to determine the source first. Given the age of the house, it may even be multiple sources.

 

[Daniel Dudley]

Google up Radonseal. This is what you need, and it is easy to use. Cost me about 150.00 to do my garage, and it really helped.

 

[Zeke]

So many garages built against soil. I can't ever see that better than excavating a pad and having retaining walls outside the structure.

I know, that doesn't help. I guess I'd hire an army of elves to dig out all the way around, seal and provide drainage.

 

[tdt]

Great idea. You have to determine the source first. Given the age of the house, it may even be multiple sources.

I should clarify the statement. The garage is a detached structure. I also should mention that it shares a stone wall (not a load bearing wall) with a barn.

 

[GeorgiaHybrid]

The house was built in 1875 and the garage over a period of time. I am the second owner with no knowledge of how it the concrete was poured. I suspect no external barrier is in place.

You guys must live a LONG time where you are. The house is 136 years old and you are the second owner?

On to your problem, it sounds more like a condensation issue instead of water coming thru the wall. Try running a dehumidifier for a month and see what happens. You can also run a whole house fan up thru the ceiling to have enough airflow to eliminate the problem if it is from condensation.

If it is coming thru the wall, you will have to seal it.

 

[tdt]

You guys must live a LONG time where you are. The house is 136 years old and you are the second owner?

On to your problem, it sounds more like a condensation issue instead of water coming thru the wall. Try running a dehumidifier for a month and see what happens. You can also run a whole house fan up thru the ceiling to have enough airflow to eliminate the problem if it is from condensation.

If it is coming thru the wall, you will have to seal it.

Well, we really dont live that long, but apparently this families children did not stray to far. The son took the farm over from the parents. Rural Wisconsin I guess.

I am game planning for next spring so I will try for the dehumidifier first then seal afterwards.

 

[kbs2244]

In 1875 they didn’t seal in any way.
As said get good outside drainage with gutters and downspouts to keep the outside dirt as dry as possible.
This may include a gutter job on the barn.
(Standing out in the rain and watching where the water comes from and goes to would not be a bad idea.)

Meanwhile, inside, you need 24/7/365 air circulation.
Garage sale ceiling fans are cheap and will work.
So are drugstore window fans.
The ceiling fans last longer since they are designed to be always on, but they are a bit harder to install.
The window fans are plug in and aim. But even at the slow setting, which is plenty, I have had the bearings go dry in 3 years of always on. But a drop of oil is cheap or even $15.00 for a new one isn’t bad.

 

[tdt]

I think that I am going to try the paper trick inside, watch the drainage during the next rain and plan on getting some ceiling fans and possibly a dehumidifyer next spring

 

[Will67]

If it is coming thru the wall and floor??? Then I suggest doing some reading on moxie international's website at moxie-intl.com

I have used this to seal blue cross's building in El Dorado Hills ca.