Problem with garage floor

[cathyz]

Hello everyone,
We have an existing detached garage we would like to remodel to convert to office/family room space. However, one issue we have in this garage is the floor. We live in Western Washington. In the fall and winter, the floor gets very wet. There are no leaks, so it seems to be some sort of condensation.I have read about vapor barriers, and we are not the original homeowners, so we have no idea if one was installed. My guess would be one was not installed. Is this a common problem and how can we address it?
Thank you in advance for your input,
Cathy

 

[Jackfre]

For the weather you folks have been having I’m not surprised you are getting condensation. Is the floor level above grade or is this water entering the structure? You may need to install area drains at the foundation perimeter. You need to ventilate the space. When you do your re-model I think your contractor will pitch a mini-split to you, which will be the correct method of controlling the atmospheric moisture and will give you good heat/cool as well as dehumidification.

 

[larry_g]

Hello everyone,
We have an existing detached garage we would like to remodel to convert to office/family room space. However, one issue we have in this garage is the floor. We live in Western Washington. In the fall and winter, the floor gets very wet. There are no leaks, so it seems to be some sort of condensation.I have read about vapor barriers, and we are not the original homeowners, so we have no idea if one was installed. My guess would be one was not installed. Is this a common problem and how can we address it?
Thank you in advance for your input,
Cathy

A couple of simple things;

Tape a 3' square of clear plastic to the floor and seal around all 4 sides. If moisture is rising out of the floor it will accumulate under the plastic. If the floor gets wet and under the plastic is dry then it's condensation.

Condensation happens when warm moist air hits a cold surface, your floor or most commonly seen on the bathroom mirror. In my shop I have to keep the doors closed in spring and fall or the condensation is bad. So pay attention to when the floor gets wet, and is it due to warm outside, cold inside, and big doors open to allow the rapid influx of warm wet air.


So once you determine what is causing the moisture, then a plan can be developed. Is this a metal building? Does it have and insulation or vapor barrier in the walls? Is it a 'tight' building or can outside air easily enter around openings? Are there any metal items in the building that also get wet with condensation?

lg
no neat sig line

 

[T_R]

I would lay down some sort of penetrating sealer or a drylock type material. Then to be sure put a thick plastic vapor barrier over that. Then build a wood subfloor over the concrete from 2x4 and 3/4 OSB.

 

[ard]

1. As above, you need to deterimine where the water is coming from- condensation from the air onto the floor or permeation from the ground up into the slab.

2. What interior floor do you want to install? Wood floor over top? Tile? Raw concrete with sealer? Epoxy?

3. Once you answer #1, then folks can determine how THAT can be controlled, and THAT will tell you wihc of the #2s is possible.

 

[James-W]

I would think the very first thing to do is to figure out why the floor gets wet. If the water is coming up from under the slab then you need to address that before you proceed. If it caused by condensation, that you can deal with fairly easily. But until you know for sure what is causing the water issue, personally, I wouldn't start the conversion.

 

[James-W]

Forgot to mention, welcome to the forum.

It helps to put your location under your login name, sometimes the answer to a question depends on location.

 

[wssix99]

This is a common problem and will happen whenever warm (relatively) humid air hits a cold slab. If you change one of those variables with heating, ventilation, and/or cooling, the condensation won't happen. (This is why you don't see this problem inside your house.)

If the garage stays heated and cooled like a garage the problem will persist. If you convert it to more of a living space, your experience will change.

If you can share what your plans are for heating and cooling the space and the conversion, folks can pitch in options to help with this problem. (Electrically heated tile floors, etc.)

 

[James-W]

This is a common problem and will happen whenever warm (relatively) humid air hits a cold slab. If you change one of those variables with heating, ventilation, and/or cooling, the condensation won't happen. (This is why you don't see this problem inside your house.)

If the garage stays heated and cooled like a garage the problem will persist. If you convert it to more of a living space, your experience will change.

If you can share what your plans are for heating and cooling the space and the conversion, folks can pitch in options to help with this problem. (Electrically heated tile floors, etc.)

How can you be certain the problem is condensation? Not saying you are wrong, you could be right as rain. I am just wondering how you can be certain of it.

 

[2level]

I'm also in Western Washington. No problems with condensation in my insulated stick built garage, but when I had a metal shed, condensation was a problem for a couple of months per year. Metal roof dripped pretty bad at times.

 

[dave89iroc]

How can you be certain the problem is condensation? Not saying you are wrong, you could be right as rain. I am just wondering how you can be certain of it.

read post #3, he describes it

 

[James-W]

read post #3, he describes it

I did read post number 3, but the opening poster did not come back and say she did that and tell us what happened so we don't really know where the water is coming from.

 

[LegacyIndustrial]

Hello everyone,
We have an existing detached garage we would like to remodel to convert to office/family room space. However, one issue we have in this garage is the floor. We live in Western Washington. In the fall and winter, the floor gets very wet. There are no leaks, so it seems to be some sort of condensation.I have read about vapor barriers, and we are not the original homeowners, so we have no idea if one was installed. My guess would be one was not installed. Is this a common problem and how can we address it?
Thank you in advance for your input,
Cathy

If you have:
Cold floor & warm air temps going into spring and going into fall.. warm floor, cold air temps...

Try a fan in the room before you get too fancy could be a temperature delta issue. There isn't a coating that can help, just move the air.

 

[wssix99]

How can you be certain the problem is condensation? Not saying you are wrong, you could be right as rain. I am just wondering how you can be certain of it.

I didn't say it was. I said its a common problem.

It's more common for midwesterners in the spring and even more common for northwesterners more often. (They have a great supply of warm humid air...)

 

[Garage Flooring]

if you have:
Cold floor & warm air temps going into spring and going into fall.. Warm floor, cold air temps...

Try a fan in the room before you get too fancy could be a temperature delta issue. There isn't a coating that can help, just move the air.

this

 

[borderhardwood]

Hi there! I am new here and I was looking around and found this thread quite interesting. I think it is important to check in first why there's water coming in or why the floor gets wet. So that way, we can find the solution that will diretly hit the problem. Also, it depends on what of type of flooring you want to install.