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Water in Garage?

I need help. My garage has a drainage problem. Each time it snows or rains and we park in the garge all the water from our vehicles drips off the cars and runs towards the house. Some water is actually seaping underneath the walls and into the house. We are afraid that mold and other types of problems could exist. What do we do?? Help please?? Do we need to do something to the garage floor???

Re: Water in Garage?

The water seeping into your home isn't a garage problem, its a waterproofing problem in your house. Do you also get water into your home when it rains? Water should not be seeping into your home. Get some waterproofing estimates and find the best way to prevent these problems in your home. YOu may need a new concrete garage floor.
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Re: Water in Garage?

It is a garage problem. No water comes into the house from rain. Due to the massive amount of snow we receive in the Black Hills, our vehicles melt a huge amount of water onto the garage floor. The water from the melting snow has no where to run. It runs straight towards our house and seeps underneath the sill plates on the garage floor. This is why water has damaged much of the sheetrock and walls. I need to figure out a way to keep water away from the walls and divert it someplace.

A. Spruce
Re: Water in Garage?

Park outside ... ;):p

The garage floor is probably sloped about like it should, from the back to front (towards driveway ). From the pictures I see that the house wall is next to the garage door. The way this SHOULD have been done is a curb would have been poured so that the house was either isolated OR 4" above the garage floor. Technically speaking, the house should be at least 4" above the garage floor so that gas fumes stay in the garage and don't seep into the house. But to talk about that now is like closing the barn door after the horse has run away.

I would strip the drywall off the garage side of the wall up high enough to at least remove the damage 6" may do it. Snap a chalk line or draw a line along the length of the wall and remove just that portion of drywall. Inspect the sill plate and framing to make sure no further damage is present. If there is damage, replace it with new materials, pressure treated for the sill, regular lumber for the studs. Scrub and wash the sill plate and concrete slab to remove any dirt and debris and allow to fully dry.* Apply a heavy bead of sealant along the floor/sill joint and lay off with your finger or other tool.**

* - You may need to wait until spring/summer when the weather is warm and dry and no further water/snow is being brought into the garage. It is important that the surfaces be clean and fully dry for the caulk to adhere and seal.

** - Read the label for clean up of the caulk. You will want to have latex gloves on OR use a disposable tool. Laying off the caulk does two things, it forces it into the joint and it finishes the surface to a nice appearance.

As for what type of caulk to use, it should be an elastomeric type, not silicone or latex. Read the labels, what you want is something designed for concrete that is pliable through the temperature range of the job. I don't have a recommendation because I don't use it very often and labels/brands change.

Replace the damaged drywall with the same thickness - should be 5/8" which is code. Paper or mesh tape is acceptable with at least one coat of drywall compound over the fasteners and joints.

Re: Water in Garage?

You are right, it is sloped, but it sure doesnt go towards the driveway. It seems like it slopes directly to the house. Would you recommend I place some 8" concrete blocks on the garage floor in front of the sill to keep the new sheetrock from receiving future water damage. Any ideas on how to affix the concrete blocks to the floor. Silicone or concrete?? Which would work best?? I really wish I could install some sort of drain or at least a groove to direct the water to the outdoors?

I would probably have to rent a jack hammer for that job???

Just looking for a simple, satisfactory solution. Less time, less money.....

Re: Water in Garage?

Yep -- as Sprucey mentioned the pad should be lower creating a barrier between the house and the pad.

Short of tearing things out you might need to cut a drain trough for the water to flow out the garage door. If the pad itself doesn't slope out then the trough waould need to be cut so to create a slope for the water to run. You would start it shallower at the beginning and deeper as you approach and beyond the door.
Or --- perhaps cut a strip out of the pad the entire length --- dig the gravel to provide a slope --- install drain pipe to direct the water out.

I don't believe blocks are the way to go --- they will intially provide a damn but will eventually become saturated and if too close to the home's structure will cause the same issue you currently have.

2 cents.

A. Spruce
Re: Water in Garage?

Describe for me the orientation of the garage to the house and in which direction the floor slopes. The floor SHOULD slope towards the roll-up door and out to the driveway. It SHOULD be level from side to side so that water flows to the driveway, not out to the sides.

You might be able to cut the slab and install a drain system, however I am leery to suggest such a thing because of introducing significant moisture under the slab and possibly house foundation. This could cause the problem to worsen due to the slab settling in the soft ground.

Re: Water in Garage?

Please check out the diagram I have added to this post. I hope that helps explain the orientation better and where the water is running.

Correction of Error: Water has actually seeped under the wall and into this room.

I wonder if the slab was poured incorrectly and slopes towards the drain in the furnace room?

Could it be that since I am on a huge hill, my garage slab has settled or was again poured incorrectly?

How in the world would you place or cut a drain to lead to the exterior???

Thanks for the suggestions!

A. Spruce
Re: Water in Garage?

Thank you, your drawing confirms the picture in my mind.

As mentioned earlier, the garage floor is likely the major culprit in that it was poured incorrectly. The primary problem is that it is flush with the house floor when it should be a minimum of 4" below the house slab. Second problem is either the slab was poured sloping towards the house or due to incorrect grading and prep, it has settled on the house side. My suspicion is more that the floor was poured sloping to the house and that it's quite likely once piece from the garage into the house slab.

Question, was the house/garage wall installed after the house was finished, meaning is there an elevation change in the floor somewhere like living space was extended into the garage. This would explain the slabs being the same height if it was once originally part of the garage.

Fixes: Without seeing the site for myself, I can't really say what the best course of action would be. Cheapest that would work and probably last the duration of your stay in the house would be to seal the sill plate of the wall to the garage floor with Elastomeric caulk as I explained earlier. The next, more expensive thing would be to install a curb under the wall AND seal the curb/slab joint with elastomeric caulk. Third and most expensive route would be to remove the garage floor and repour it so that it slopes to the centerline of the garage and out to the driveway. As for installing a drain, that would depend on the elevation of your lot and the ability to redirect the water to the driveway or storm drain system. If you've got a natural slope away, then it should be fairly straight forward, if not, then you'd have to install a collection box with a sump pump to eject the collected water. My concern with installing any of this in the garage would be causing the slab at the wall to settle, making the problem worse.

Re: Water in Garage?

Traditionally in our area, houses are sold with the basements unfinished. This is so that people can afford to buy more house and have the opportunit to finish the bottom floor as they wish.

I am not sure about when the garage wall was added. I am pretty positive the interior side was completed when the house was built. The exterior - open to the garage could have been left for quite some time.

Currently, the garage is not finished. The sheetrock and tape is up, but no texture and no paint on the walls.

My house does not have a basement. It is a split level. The lower level is off the garage. So there is a good chance the lower level was finished after the first owners took possession.

Anyway...I like the curb idea. I think the higher I can keep the sheetrock up off the concrete floor the better. Might eliminate my problem of the sheetrock getting wet in the future.

I still have no clue on how to divert the water to run out of the garage instead of towards the house.

Too bad this curb couldnt contain some type of channel that would cause the water to run out.

We just received some snow...yeah....so I am closely watching the water in my garage run. I put towels and blankets rolled up on the floor as an attempt to keep the water away from the wall......what a mess.


A. Spruce
Re: Water in Garage?

This just occurred to me. You know what you could do that wouldn't involve any destruction, construction, installation or manipulation of anything? You could cut two or three saw kerfs into the slab about 1/4" to 3/8" deep that run the length of the garage to the corner of the roll up door. Basically, along the side of the car. The kerfs would not affect the integrity of the slab, yet would provide barriers for the little bit of water we're talking about. Because there's no quantity or flow, this should be able to keep up with any run-off produced by the cars.

If this seems like a viable option, I will tell you how to go about it.


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