DIY Home Improvement Forum banner

New garage floor with pooling water

10K views 10 replies 6 participants last post by  Gary in WA 
#1 ·
Hello -- We recently built a new house and have water pooling in our garage - I have read the other posts on this topic so am somewhat familiar with what many of you suggest to do -- my situation is a little different. First the problem - when we park the vehicles in the garage with snow or rain on them the run off water pools in front of the door into our house (pretty large area approx 3' x 8') and when it rains water runs under the door and also pools in front of the door into the house. We ran water in the garage to see just how bad the problem is and ended up with 3/4" of water - about 65 gallons - before it ever ran out the door. The reason our situation is a little different is because we still owe a significant amount to our contractor and he has offered to do what ever we want to fix it. Our options are replacing the floor or putting in a drain. They have mentioned a "french drain" which some have told us not to do. Do you recommend just having them replace the floor and get the slope right, leaving the current concrete and putting in a drain of some sort OR replacing the floor and also putting in a drain? We do not currently have a drain and have been told by several not to put in a drain. What do you suggest? Thanks!!

Sorry so long - first time I have ever posted so let me know if I am doing something wrong!!
 
#2 ·
Before you even consider putting in a drain, check with your local code enforcement official about whether it is code in your area. Many areas prohibit drains in the garage, because chemical spills (gasoline, oil, fertilizer, whatever you have in the garage) would migrate into the drain, and could cause a fire or explosion hazard. You may want to do the check with the code enforcement official yourself, since your contractor cannot get the slope correct, perhaps you would not fully trust him to determine if a drain is code or not.

As for the slope, you want your garage to slope towards the street, so any meltwater runs out the door onto the driveway, but you already know that. Minimum slope is typically 2 percent, but again check with your local code enforcement official. Once you know the rules, ask your contractor to propose a solution, which could involve an overlay, total replacement, or selective grinding, whatever is required. It all starts with an accurate map of the elevation of the garage floor, so you can see where the low spots are. You can prepare such a map the easy way by hosing down your garage, as you have already done, and marking the depth of water that remains. This will not tell you the slope on areas where no water pools, so a topographic survey with an instrument is a better idea, since it will give you the entire picture of the garage condition.
 
#3 ·
Daniel's right about the drain. You certainly need to look into what code allows for the discharge, if any. It sounds like the contractor maybe suggesting just draining the water into the aggregate below the floor, which IS NOT a good long term solution.

My vote would be for replacement of the floor. The home is new after all, and putting a drain in an akward spot, like right in front of the door, is merely a band-aid IMO. Direct & keep the water outside, where it belongs.

The 2% grade Daniel mentioned is ideal, but not always feasible in some larger garages. Especially if your driveway is existing outside the door. It could lead to more restrictions on height now. I've had success with garage floors draining with as little as 1/8" per foot (close to 1%), BUT the floor HAS TO BE VERY FLAT to make this work. Something tells me that may be easier said than done with this contractor, as a 3/4" dip in the floor is fairly substantial for a professional IMO.
 
#4 ·
Do state/local rules require your contractor to be licensed?

If yes, does any of the paperwork have his license number? If so, you could check with authorities to make sure it is a valid number.

If it is not a valid number, I'd definitely want someone with the proper credentials to do whatever you choose to do, and you should have a lot of leverage for a big discount when it comes time to negotiate final payment to the first guy.

Even if the guy is licensed, once you choose the approach you want, since the guy offered to do whatever you want to fix it, one option would be to get an estimate from another professional and tell the 1st guy that what he must do to fix it is deduct that amount from your bill, so you can hire the other (hopefully better) outfit to do the work.

If he refuses to make the deduction, then before burning bridges or refusing to pay be sure to talk to an attorney familiar with mechanics or contractor liens about your options. As a compromise maybe another contractor would just review the proposed plans and methods and drop in to eyeball the job.

I hate these things, best of luck!

Steve El
 
#5 ·
dtk: that is OUTRAGEOUS. Very poor workmanship; not even close to being acceptable. Take the advice of the folks above, and get it RIGHT. It sounds like you need another contractor who will pour a good floor; get his/her specs in writing, too. Something like 1/8" in 10' is very doable, and that does not mean 1/8" every 10'; it means an 1/8" variation from perfect. I could have poured your floor better than what you have, and I am not a pro.
 
#6 ·
Thanks so much -- we are getting the floor replaced -- Now what we need to decide is if we should just go ahead an put in a drain while the floor is ripped out. Yes code wise we can put in a drain. The garage is approx 30 x 30. Any strong opinions for or against a drain?
 
#7 ·
Were it mine, and code allowed a drain to a sewer line, I'd have one in the middle, or one in each vehicle area. What you'll have to watch is that this is an end drain, and the trap may dry out and let gasses up. Dump in water periodically. Check to see if end drains (my words) are allowed in your area.
 
#8 ·
I would go for the sloping floor rather than a drain. If a gas tank ruptures and spills onto the sloped floor, it will head for the big door. In the drain the gasoline will be deposited at the street? not in the sewer- onto a blacktop? roadway where it could all catch fire. Remember the code says sloped in the vehicle area: 2009 IRC SECTION R309 GARAGES AND CARPORTS

R309.1 Floor surface. Garage floor surfaces shall be of approved noncombustible material.

The area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.

Gary
 
#9 ·
Gary: The gas is a problem I had not thought of; I guess that is why they pay you the big money here. Remote chance, but if it did happen, it could get ugly. I don't know if the garage door is any better, though; a river of fumes and one spark would torch the house. Either way, bad news. I see that the code you quoted does not preclude drains, so maybe it is a toss up? Dunno. Gasoline is one of the nastiest chemical bags we have around, for various reasons. If it were not so ubiquitous, I am sure it would be outlawed. j
 
#10 ·
Glad to hear you're getting a new floor out of this, as it's the only long term cure to the problems.

As for drain vs. pitch to OH door, I'd suggest the latter in most cases. Mostly because it's generally easier to pour w/o water ponding issues, as a floor drain floor can be far more complex and has better chances of water backing up at/under the garage door if the installer doesn't know what he's doing.

BTW, where did the contractor say the water was going to drain, outside to grade or into the sewer?
 
#11 ·
If I had a drain between my two cars and a radiator was leaking, it would not be seen as quickly as if it drained to the big door where I enter from. Your situation may be different. Just another thought....

Gary
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top