Just Bought House With Below Grade Garage, Help!

[jrdn]

Hello everyone! I'm new here (clearly). I just purchased a house with a driveway slope going towards the garage and the rest of the garage being below grade. There is a Canyon behind my neighbors where water naturally flows, but sadly, it makes its way in the garage. This garage will be my brewery and office, ideally. The last rain, I noticed water inside, so I had a gutter installed and a concrete shed pad put (above grade) in the back with "drainage" under it.

With all that said, I'm afraid that water will seep through the concrete patio and shed pad, get to the dirt, then make its way into the foundation then into the floor sill plates, etc, etc, etc.

It doesn't rain much in San Diego, so I'm not sure how big of an issue it is on the normal day to day, but on an "El Nino" year, I'm afraid all my stuff could potentially get ruined by a massive storm? We get rain tonight, so I'll see where most of the runoff is going.

What are some options to keep water outside and away from the internal walls creating potential flood or mold issues?

Some of my ideas:

1. Raise garage & foundation (expensive???)
2. Secure structure to outside temporary foundation pads, cut structure & framing (building is now "floating"), frame & pour new stem wall (probably expensive but less than 1?
3. Just fix drainage issues as I see them and live with it (hopefully extreme down pours don't flood)
5. ........???

Thanks everyone!

 

[theoldwizard1]

Install a large gutter drain across the door. Connect it to 2 a French drains along the sides. Make sure everything is over sized.

For a nice dry floor in the office area look into something like DRICORE.

 

[PoorUB]

I would recommend drain tile around the sides, lower than the garage floor. Hopefully you can drain it down the hill side.

 

[BearsFan315]

generally same issue here, all the rain water rain in and flooded garage. downpours would have 1+ inches of water on my floor.
i cut the front end of drive at garage put in a drain, then plumbed it downhill towards curb. also cleaned up and graded area along both sides of garage to drain away. workd so far now for 5+ years !!

did this on my garage, got the drain and covers from lowes. NDS stuff, rated for car weight as well as the PVC pipe to drain to the street. and a pop up emitter.

rented concrete saw from local rental for 1/2 day, cut a slot in driveway, dug out, put in sand/ rock base sloped drain to the drain side, returned saw & rented a small mixer and bought bag crete, mixed and poured in. did it all in an afternoon.

Tell you it works GREAT no more issues with water in the garage !!
worth the time and money !! i go and flush it out a few times a year dues to debris and leaves.

 

[FMB4]

Welcome aboard jrdn. All of the advice above very good. Meanwhile, we had somewhat similar drainage issues at our previous house due to the driveway slopping towards the garage and walkway to front door. We solved this problem by digging several ditches and running 4" corrugated - perforated drain pipe covered with 2" gravel, which was in place before along the house. We also dug out and ran said pipe under the cement walkway to the front door.

 

[CraigStu]

4 me the question is do you have some of your property that you can run drains to that is lower than the garage? If so would water coming out of a drain pipe there run onto your neighbor's property? If you start by digging around the garage down 6-8 inches to start w/ drain pipe, that pipe has to have a slight down slope for it's entire length. Is that possible? One other thought is to run drain pipe to a dry well. That may not be the correct term but I am thinking of a large hole dug in the yard, and filled w/ the proper stone and then covered back up w/ grass. So that provides a place for the rain to go as long as the total amount of rain is less than it's volume.

 

[firebirdparts]

I agree- lowering the world is very cheap compared to raising that garage. It's obvious you don't have much room to work. Ideally you'd have:
1. Gutters
2. Drains beside the foundation
3. Slope on all 4 sides, no exceptions
4. Floor above grade everywhere, no exceptions.

Then everything drains to daylight downhill from the garage.

That's the idea. Obviously not everything has to have all 4, but it looks like you are at least above grade. That's a start.

 

[FredWanaker]

I lived in San Diego for many years and owned a property like yours. Never had a problem, although a store I once worked at on El Cajpn Blvd near Texas Street did. The key to your problem is figuring out where the water is coming from and blocking or diverting it. If you just throw money at it you might eventually fix the problem, but if you miss it then that is a lot of money spent for no gain. For example, where does the water show up first? is it one corner, one wall, the opening on a driving rain etc..

 

[PoorUB]

Good point.
I have a buddy that lived on a large country lot. He was towards the down hill end of the development and when it rained hard water would come down the hill side from the neighboring properties and he would have some water issues in the garage and basement. He tried a few things, then went a bit crazy and hired a guy with some excavation equipment and on the high end of his property he dug a ditch and directed water around his property, problem solved! It wasn't a huge ditch, only a couple feet deep, but he told me he was surprised at the amount of water flowing out of the ditch in heavy rain.

Now this was a bit extreme, but perhaps the OP might consider something like this. Not knowing how his lot is laid out it might be impractical, but something to consider.

 

[budget76]

do you plan on putting flooring down? If so, you could build a false floor with a little air area in case some water did get in. you would want to make sure it could vent so you don't get mold, but then at least you don't have anything sensitive on the concrete. Making the water go away is the big key, but this may be a "safety net" appraoch for your stuff

 

[jrdn]

I lived in San Diego for many years and owned a property like yours. Never had a problem, although a store I once worked at on El Cajpn Blvd near Texas Street did. The key to your problem is figuring out where the water is coming from and blocking or diverting it. If you just throw money at it you might eventually fix the problem, but if you miss it then that is a lot of money spent for no gain. For example, where does the water show up first? is it one corner, one wall, the opening on a driving rain etc..

Yep. This is what I did. I spent $2,300 by installing a drain in front of the garage and a concrete pad for shed storage behind the garage. I originally thought water came in through garage since driveway slope was going to it, which it did. Sadly, after last night's rain, water came under the newly poured concrete pad behind the garage... and it wasn't even that big of a rain event.

My current thought is that to properly do this, I'd have to cut the concrete pad out a foot or two, and dig even deeper for a french drain. If another storm event presents more leakage through other sides, I'd have to do the same to the entire length of one side where they added a patio, so this is even more work. So I'm guessing to install french drains around the entire garage, I'd have to have a sump pump at that point since water naturally flows behind neighbor's yard into the Canyon but this may end up being more water. With all that said, am I now looking at ~$5-6k to do gutters when a garage "lift" or foundation wall retrofit would cost ~$10K? Do I full commit or do drain patches.

I guess I just have to figure out what all costs are going to be and decide.

 

[jrdn]

do you plan on putting flooring down? If so, you could build a false floor with a little air area in case some water did get in. you would want to make sure it could vent so you don't get mold, but then at least you don't have anything sensitive on the concrete. Making the water go away is the big key, but this may be a "safety net" appraoch for your stuff

I was originally going to put flooring down but yeah, I want to avoid the mold issues as this may be an area my future (wife's pregnant) kid will hang out with me in. This garage was "remodeled" and they replaced the floor sill on one side and I found rot in another section of the floor sill making me believe this has been an issue for roughly the 50-98 years of it's existence and the flippers just put makeup on a pig.
All they had to do to make this right was to just remove dirt from the back yard prior to pouring the concrete patio to get everything back to grade and even more dirt away from the house itself.

 

[4xdog]

This is attached more in jest than a serious comment, but it seemed appropriate for your thread, @jrdn. The announcement of this "Dam Easy® Flood Barrier Door Dam" came this morning in an email from Trademark Hardware in Spokane. They claim to have options for larger doors.

https://www.tmhardware.com/dam-easy-flood-barrier-door-dam-ultimate-flood-gate-up-to-43-doorways

 

[mikedodge]

Our garage is essentially part of our basement. We only had problems with water coming in at the end of winter when the snow banks melted which at least you shouldn't have a problem with. A large grate the length of the door right at the edge of the slab put an end to that.

 

[jrdn]

Our garage is essentially part of our basement. We only had problems with water coming in at the end of winter when the snow banks melted which at least you shouldn't have a problem with. A large grate the length of the door right at the edge of the slab put an end to that.

Water came in on 1/2" rain through the bottom of the slab (the side buried in dirt).

 

[drivesitfar]

JRDN: first off welcome to GJ!!
it's a bit hard for me to follow your issues cause I guess I need more pictures when you post new issues or solutions. If you are able to post pictures in each of your posts it might help us better help you. it looks like your cool (new?) patio is above your garage floor level? did you say your floor is wood on top of cement in the garage with maybe flooring on top of wood? I'm guessing your world is crazy at the moment with a baby on the way and a new house so you probably were told to spend the $2300 for a drain fix that was supposed to but didn't?

one thing you could do is check framing behind sheetrock to see if it's rotted at the base. if it is a small cement block wall around the perimeter with a new cement floor might be your best option especially if water is coming up from under garage thru cracks in old cement.

this is about the time of year I always wished I lived in San Diego cause love the weather and the ocean not to mention pelicans. I remember studying for the California real estate exam next to a pool in your fine city one January about 37 years ago and missed passing by 3 points cause I was watching the scadly dressed gals at the pool instead of reading that chapter. then I came home met my dream girl shortly after that and had 5 kids, but still would like to spend my winters in your part of the world.

first baby?

good luck!!

 

[jrdn]

JRDN: first off welcome to GJ!!
it's a bit hard for me to follow your issues cause I guess I need more pictures when you post new issues or solutions. If you are able to post pictures in each of your posts it might help us better help you. it looks like your cool (new?) patio is above your garage floor level? did you say your floor is wood on top of cement in the garage with maybe flooring on top of wood? I'm guessing your world is crazy at the moment with a baby on the way and a new house so you probably were told to spend the $2300 for a drain fix that was supposed to but didn't?

one thing you could do is check framing behind sheetrock to see if it's rotted at the base. if it is a small cement block wall around the perimeter with a new cement floor might be your best option especially if water is coming up from under garage thru cracks in old cement.

this is about the time of year I always wished I lived in San Diego cause love the weather and the ocean not to mention pelicans. I remember studying for the California real estate exam next to a pool in your fine city one January about 37 years ago and missed passing by 3 points cause I was watching the scadly dressed gals at the pool instead of reading that chapter. then I came home met my dream girl shortly after that and had 5 kids, but still would like to spend my winters in your part of the world.

first baby?

good luck!!

Awesome story! Yes, it's great here. I'm an avid surfer so I enjoy being close to the water. The drains was what I thought would be a fix and the guys who did it were more handy-men than anything and did sort of shotty work. At the moment, we're thinking we'll have to just hope small drainage fixes can do for now and we can instead save and invest money into an actual house addition (office + small room). A few contractors have already said that's all we can really do without spending a ton on the garage. Still waiting on some quotes for just "de-grading" the whole back yard and removing the concrete patio to essentially lower the entire yard grade itself. He mentioned that houses this old (~100 years) accumulate so much dirt from adding / removing plants over the years that it may have once been at grade. He's also quoting raising and re-pouring foundation, but if numbers end up being well over $5-10k then I'd probably just save it to spend on a home addition.

Anyway, hope you can one day make it back to SD.

 

[drivesitfar]

here's a couple bad pics of what I was thinking might be a good fix until you do a full on remodel/addition. i'm not sure what your skills level is or how easy or inexpensive your handyman type help is, but this is maybe a 7 on a scale of 10 on how hard it is to do. support the ceiling/trusses, cut out the rotted wood at the base (i'm assuming it will be if water and dirt and air has been in the mix for years), then lay a row of cement block with or without rebar and j bolts to put on a treated 2x6 and splice in a new wall up to where the wood isn't damaged.

best of luck with your surfing (kite surfing yet?) and since my youngest just moved from Santa Monica (lived there 2.5 years for new job out of college) to Miami I'm not sure when i'll get to San Diego, but hopefully soon cause one of my favorite members on GJ lives just east of LA. have you checked out Don's Party Garage thread? here's the link and keep on towel on your laptop cause drool can and will happen when following along on his thread.

https://www.garagejournal.com/forum...big-party-garage.153099/page-213#post-9298135

cheers