Drainage for back yard

[jeff3447]

I hope someone can answer this question for me. I have a drainage problem in my backyard. Im planning on rerouting a gutter that drains into the backyard to my sideyard, then running drain tile to it to drain it into my front yard. The question I have is this, the path that the drainage tile will take is the future location of a patio that Im planning on building. The drainage tile will run pretty much down the center of where the new slab will be. I plan on having 4 inches of gravel as a base then pouring 4" of concrete. Will the drainage tile cause problems for the slab? Is there anything I should do to prevent problems? Should I use solid drain tile rather than the flexible type?

Thanks for any and all help,
Jeff

 

[d.n.f.]

The flexible will not only take your water away but also take any water it finds as it snakes. This is the kind with the sock on it. The non-sock kind won't.
Flexible moves and since you are not burying below the frost line this should be a consideration. Especially with it being under a slab.

We have always laid it on top of a good base of crush, with a lot of crush surrounding it.
Make sure you don't lay it level!

 

[jeff3447]

Thanks for the reply thats exactly what I wanted to know. The builder had told me it would cause the slab to crack, he wanted to run it along the perimiter of the slab which I thought would be worse.

Thanks again!

 

[Highbeam]

The thing about using perforated pipe for the conveyance of your downspout water is that the perforations can work both ways, the perforations can take on additional groundwater and route it to the end of the pipe or the perforations could leak out the downspout water making a wet area even wetter. I would keep the two lines seperate, one solid pipe for downspouts and one for your curtain/french/trnch drain.

In almost all cases, the solid perforated pipe from HD is superior to the flexible type. For one thing, the perforations on flexible pipe are all around the pipe so water tends to come and go as it pleases. Solid pipe only has two rows of holes that are oriented downwards to accept water and get it out. Flexible pipe crushes more easily. Flexible pipe is harder to lay at a proper slope. Solid pipe is a little more expensive.

Oh, I don't believe in sock wrapped pipes. The socks only work where directly over a perforation and they are the first thing to clog. If you must use fabric then either wrap the entire gravel trench or put it on the top before backfilling with soil.

You can properly run a french/trench/curtain drain under a slab. The reason that it could crack is that if you didn't use any fabric the pipe or gravel voids could pull in and convey the surrounding soil which would make a sink hole which would reduce the foundation for the slab making a crack. Under the slab wither switch to solid pipe and backfill with soil or completely wrap the gravel trench section with fabric (aka a burrito drain) and run perf pipe.

 

[jeff3447]

Thanks Highbeam, this makes good sence and thanks for the tips on the cleanouts. Sounds like this is the best option for me.

Thanks again,
Jeff

 

[d.n.f.]

That makes sense Highbeam. I am only going with what the guy I worked with in the past did. Not saying he was an expert, cause he wasn't.
You get shown something and you use it cause it works until it doesn't. Or somebody splains something in a better way.
Thanks for the splaination.

 

[burntime]

Highbeam hit the nail on the head!

 

[ansehnlich1]

I just built a new home a year ago and we used form Form A Drain for the footer forms. It is a heavy rigid plastic. It acts as the drain for a homes footer foundation.

ANYWAY, you wouldn't use it for your application, but the reason I mention it is that this stuff is strong enough to handle the weight of 6 to 8 feet of back fill on top of it, so if I were you, I'd run a heavy, rigid, NON-perforated pvc/plastic pipe under that slab.

Just make sure when you lay that pipe, you use plenty of stone for a bed, as already mentioned.

Do it a couple months before you lay your concrete slab, so any settling of the soil can occur before you pour your concrete OR soak it real good with a hose a couple times, let it dry out, run over it with your truck a couple times, pound on it with a big tamper of some sort, just make sure its settled BEFORE you pour.