Learn me interior French drains

Every time it rains, the garage floor gets wet. It is safe to assume this is also a cause of the high humidity in the living room on this floor, but it's hiding behind the walls if it's leaking there.

There are no major cracks or holes anywhere that I can see, it just seems to seep in.

The entire floor of the house is below grade, so digging up the outside is both beyond my skill set on a hoe and prohibitively expensive. 

I understand there are 2 main types of indoor French drains on the market. One that goes inside the bottom course of block, and one that is cut into the floor around the perimeter of the space. 

I can operate a walk behind saw and jackhammer, so the type that is cut into the floor interests me, except it would look terrible in the living area, unless I redid that room at the same time. There's also an oil tank, some block walls, and a water heater and all related plumbing that would be considered "in the way" of any real saw work along the long side of the floor. 

So what does the hive know in this area?

Or is this a situation where I should just paint the whole thing with drylok and invest in a good dehumidifier?

It's the "below grade" part that gets my attention. My separate garage is on the lowest part of my property, and can get flooded from two directions. Idiot that owned the house originally could have put some fill dirt down, but what would you expect from someone that puts a building on top of his septic drain field?

I hadn't occurred to me that you could put a french drain inside. That's got me thinking about one under the driveway.

I'll be following this.

I'd check out some of these videos, they transformed my wife's grandmother's basement. I believe they cut the channel around the perimeter that drained into a sump pump. You would never have known it used to be a wet basement.

https://www.connecticutbasementsystems.com/basement-waterproofing/videos.html

dj06482 said:

I'd check out some of these videos, they transformed my wife's grandmother's basement. I believe they cut the channel around the perimeter that drained into a sump pump. You would never have known it used to be a wet basement.

Had you intended to share a link?

In reply to Floating Doc (Forum Supporter) :

Thanks, it's there now :-)

https://www.connecticutbasementsystems.com/basement-waterproofing/videos.html

If the garage shares air space with the house, check with the area regarding radon.

Adding a french drain inside is like leaving the door on a nuclear reactor open.  Ok, not that bad, but it is a sure way to maximize the ability for the available radon to have direct, free access to your house.  In fact, it is a big no-no around here.  You can't have one.  One of the houses I looked at when I bought had a perimeter french drain and when it was reported, the building was temporarily condemned, no one was allowed in it, and it had to be repaired, radon mitigation installed, and some special venting procedure had to happen before they could sell it.  It looked like a crime scene.  1.5 years later (a year after I bought the house I'm in), I noticed it was still condemned and being sold as HUD.  Basically anyone with $35k cash could have bought it if they were willing to do the $25k worth of work and sift through the redtape.

I would focus on the outside first.

Step 1 should be figuring out where the water is coming from. Is it coming through the walls, or up through the floor? A perimeter drain isn't going to do much if it's coming up through the slab.

You can test this by taping a 2ft X 2ft square of plastic sheeting to the floor and walls (if possible). Fully tape all edges so that it's completely sealed to the surface and wait a few days. If it only happens when it rains, you might have to wait a little longer. If any significant condensation forms on the underside of the plastic, then you've got moisture coming through that surface.

In reply to Curtis73 (Forum Supporter) :

Kind of shares air space. The garage and most of the downstairs except for the living area, has a poured concrete ceiling between it and the house, only connected by the shop hallway. There's 2 block walls in the way too.

No idea about radon. Like why I should be concerned with it, if it's a problem in the area, mitigation, anything. I just know it's a thing.

I also know digging down 12-15 feet to get to the base of the outside with only 5 feet between the the other garage and the house is not something that can happen. Like at all. I can't afford to pay someone, I'm not good enough with a machine, and no berkeleying way an I digging it out by hand. 

Guess I'll tape some plastic around. Rains every damn day here again so waiting for it to get dry enough for tape to stick will be a bigger problem.

Far as I've been able to find, code requirements don't mean anything where I'm at. Hell this house never would have passed an inspection just for the cheap ass way all the electrical has been done. Neither would any of the other houses on the street, we actually do own the nicest one. So doing something questionable to solve the problem isn't out of the question, unless there's health risks.

Oh, let me tell you about radon....

It can be a bitch!

It has serious effects on lungs and effects children more so than adults.  I'm pretty sure our oldest daughter (4) had breathing problems and ended up in the hospital from it.  Since we moved, not 1 breathing treatment needed for her.  We needed to do it about every other week when we lived in a house with a radon issue.

Our house was in New Alex.  Old house. Field stone foundation.

It took me 3 months of filling holes and gaps and everything I could think of to solve the radon problem when we were trying to sell the house.  

When we moved in, the house had a radon issue and it was supposedly resolved with a simple vent intended for this purpose.

We lived there 8 years and never knew the problem still existed.

You can't sell a house with a known radon issue.

Tl/dr:  if you haven't had a radon test done when you bought the house, get one NOW!  It is a naturally occurring radioactive gas that doesn't smell and you c ant see or taste it.  Bad juju.

French drains basically allow it to come into the house freely if it exists in your area.  (It exists in the house I grew up in, my old house, and my parents old house- Greensburg, new Alex, scottdale).  Basically all around you.

Direct the water away from the building first.  Install gutter with downspouts and some sort of piping  to drain the water away from the building.  Build up the grade against the outside walls so water does not puddle there.

noddaz said:

Direct the water away from the building first.  Install gutter with downspouts and some sort of piping  to drain the water away from the building.  Build up the grade against the outside walls so water does not puddle there.

We did both of those to our old house.  Basement went from always damp to very dry.  It works.