Advice on Garage Slab Modifications

Squiggy

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This is likely something that has been discussed prior but I'm looking for some guidance on viable options to fix up the lack of drainage in my garage. I was considering having someone come in and cut a trench around my parking spaces and then put a perforated metal over it but held off as I wasn't sure on (a) am I doing the right thing here and (b) the price I was quoted. It is a big area that I am looking at, approximately 48x24feet. Was considering a trench approximately 6-8" wide and 2" deep. Currently I have 3 areas in the garage where water will run to the walls as snow melts of vehicles etc. I'm tired of walls being soaked among other problems that can come with that.

Any suggestions for fixing this issue (not interested in tearing it all up....) without jeopardizing the full integrity of my garage slab?

Thanks.
 

maxwell

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This is likely something that has been discussed prior but I'm looking for some guidance on viable options to fix up the lack of drainage in my garage. I was considering having someone come in and cut a trench around my parking spaces and then put a perforated metal over it but held off as I wasn't sure on (a) am I doing the right thing here and (b) the price I was quoted. It is a big area that I am looking at, approximately 48x24feet. Was considering a trench approximately 6-8" wide and 2" deep. Currently I have 3 areas in the garage where water will run to the walls as snow melts of vehicles etc. I'm tired of walls being soaked among other problems that can come with that.

Any suggestions for fixing this issue (not interested in tearing it all up....) without jeopardizing the full integrity of my garage slab?


Thanks.

is there currently a drain in each of the 3 bays now? most of these grated drain systems are designed to be cast into the slab and not put in after. where does the water break and head towards the drains vs the walls? you dont want to cut through the slab IMO if at all possible. Maybe if you could post a sketch of the floorplan showing the currernt flow of water
 

busted2x

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Just dealt with this. Cut bigger section out, put drain in, pour around it, worked well, was 15k to do 90 foot drain.
e716d89831ad003ab022ebcccd5fe4e1.jpg
 

Rotax_Kid

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This is likely something that has been discussed prior but I'm looking for some guidance on viable options to fix up the lack of drainage in my garage. I was considering having someone come in and cut a trench around my parking spaces and then put a perforated metal over it but held off as I wasn't sure on (a) am I doing the right thing here and (b) the price I was quoted. It is a big area that I am looking at, approximately 48x24feet. Was considering a trench approximately 6-8" wide and 2" deep. Currently I have 3 areas in the garage where water will run to the walls as snow melts of vehicles etc. I'm tired of walls being soaked among other problems that can come with that.

Any suggestions for fixing this issue (not interested in tearing it all up....) without jeopardizing the full integrity of my garage slab?

Thanks.


Any idea how thick the slab is? If it's thick enough, you may be able to get away with bringing a small scarifier in and cutting that few inches out. It wouldn probably be one of the worst jobs you'd imagine. I scarified my garage slab after they overworked it and it shaled and that was a absolutely horrible job. You might hit bar, as by design code you should have atleast 1" coverage over the bar. If the slab was a 6"+ slab, I'd probably consider this myself.

If it isn't, you're going to have to cut it wider as was shown in the previous post, and likely tie in or dowel a new cage into the existing slab. You'll pour that and then either set steel for the trench or frame and bust out the frame work.

In saying this, if you put a trench in, how will this help the water from running to the walls? If the slope of the floor is boogered, it might not matter. If that's the case, I've used something like Quikcrete resurfacer or similar that doesn't need a big buildup to bond.
 

snochuk

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This is likely something that has been discussed prior but I'm looking for some guidance on viable options to fix up the lack of drainage in my garage. I was considering having someone come in and cut a trench around my parking spaces and then put a perforated metal over it but held off as I wasn't sure on (a) am I doing the right thing here and (b) the price I was quoted. It is a big area that I am looking at, approximately 48x24feet. Was considering a trench approximately 6-8" wide and 2" deep. Currently I have 3 areas in the garage where water will run to the walls as snow melts of vehicles etc. I'm tired of walls being soaked among other problems that can come with that.

Any suggestions for fixing this issue (not interested in tearing it all up....) without jeopardizing the full integrity of my garage slab?

Thanks.


Busted2x has the real fix with the bottom of the trench sloped, but $$$.

You can catch the melt water around the vehicles on a flat floor just super hard to make it drain.
Minimum slope to drain away water will be achieved before you get close to the reinforcing and any closer tha3/4" is to close.
To catch the water I would suggest getting a dual head scabbler and taking the floor down 1/2" X 6-8" wide with a return slope to top of floor.
This will hold lots of melt water but will not take it away, just hold it and not make a big trip hazard in the middle of the floor.
Encompass the perimeter of vehicle 2' bigger.
Again this holds the water and does not take it away.

If you want a holding sump to pump out you will be busting some floor for a sloped drain.
If your floor is sloped then you might stand a chance of draining the scabbled trough out under an overhead door.

:twocents:
 

Cyle

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A lot depends on your slab, if it's on piles, do not cut out for a trough drain like the above picture unless you know layout of piles, or you could comprise entire slab. You could just cut out a 12"x12" area and put in a sump to hold some water, even 15L is a fair amount of melt off, or could do one under where each vehicle is parked. It's a really cheap and easy way to make it a lot better.
 

Grinder

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With my same problem i used gorilla glue and made a 1/2 inch berm around parking area. Then i got thick cardboard from work and layed it down inside the berm parking area. Truck melts on cardboard, cardboard soaks up water and spreads like a sponge. Aimed furnace air diverters down and it drys the cardboard. When truck is out the heat from furnace will dry the cardboard in just a few hours. Dont use the shiney coated cardboard. The stuff from large packing boxes work well. Come spring toss out cardboard. Alot cheaper than cutting concrete.
 
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Zrock

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If it were me i would get out the laser level and a nice long strait edge and mark yourself out some lines where you park and get the big grinder and try to get yourself some slope where you park... Pretty bad the original installer did not do the job properly and put a drain and some slope in
 

Squiggy

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Currently there are no drains at all in the garage. Water runs to 3 different points in the garage 1 spot on the south wall, 1 spot on the north and 1 spot to the east part of my garage. Thats why my thought of cutting a trench in a rectangle around all the parking spots was the way to go. Depending on how much volume there was I was going to decide on weather or not to also cut in a sump somewhere.

I have had a mat for the vehicles as well, problem is if there is enough melt it runs over the side and onto the floor.

Some good advice for sure here, its a pain having to fix something like this and I definitely don't want to jeopardize the integrity of the slab. I think it is just a standard 4-6" thickness and not on piles that I know of.
 
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ZRrrr

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Exact same issue here. Has always bothered me. Some great ideas! Got me to thinking that maybe I could use a scarifier/scabbler to cut down a trench just deep enough to put in an aluminum grate that would be level with the rest of the floor. No trip hazard and a water catch of sorts. Maybe take it one step further, and cut in a catch basin at one end of the trench. Just thinking out loud.
 

Bnorth

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I like the idea of a sump cut in under each parking area. Then like you said cut a groove like they do for stress cracks in a rectangle around each spot and then diagonal cuts from the corners back to the sump.
 

ZRrrr

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I've seen this and it is a good idea. Thought about it myself. Only concern is mud/dirt getting plugged in the grooves, then the water just spills over. I have no practical experience with this so no idea if my concern is valid. I guess with multiple cuts it might less of an issue?

I like the idea of a sump cut in under each parking area. Then like you said cut a groove like they do for stress cracks in a rectangle around each spot and then diagonal cuts from the corners back to the sump.
 

Cyle

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If it were me i would get out the laser level and a nice long strait edge and mark yourself out some lines where you park and get the big grinder and try to get yourself some slope where you park... Pretty bad the original installer did not do the job properly and put a drain and some slope in

It's not the person's fault who put it in, most garages have no drains. Many areas don't allow drains to be tied into sewer. I didn't put one in my garage when I built because of that. But it's going in this winter. I'm just lucky my garage is attached, so i'm going to cut in a 12"x12" hole under where I park in each overhead door and connect drains, core hole in foundation and tie into house drain.

The worst problem is so many places try and force you to slope floor towards overhead door which is stupid unless you have a drain there. It's just perfect to have water drain to the door and freeze.
 

arff

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My garage has this plumbed into the sewer system.

You might be able to install one under each vehicle.

It is about 12 inches by 12 inches and the top lifts off.

Just an idea

Might be easy to pump water out

D95B9965-6E02-4991-B6A5-D6A210C21A47.jpeg
 

sirkdev

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I’ve seen a few sumps with a 5 gal pail level with floor, lift out dump outside and reinstall grate. Works good
 
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