diverting water away from house

[Lineman North Florida]

I have gutters on the front of my house, but the lay of the land slopes downhill towards my house which has a block stem wall foundation and I have always heard you should try to keep water away from your foundation, so what I was thinking of doing was to dig a trench about 2' wide and say 4' deep all the way across the front of the house and fill it with gravel, my question is will this work? second would landscape weed block serve as a good enough barrier to keep the 1' of topsoil from filtering into the gravel as I would want to plant grass over the gravel so it was'nt such an eyesore, I should also mention that the soil usually will soak up the water from an average rain but on a couple of occasions we have got as much as 4" of rain in an hour and this is when the water seems to not have anywhere to go, any suggestions? Thanks in advance for any info.

 

[vic4news]

A trench like that is often called a French Drain. Do a google search, there is lots of information on building them, but as you describe it's basically a trench filled with stone.

I put one in my yard to control run-off and it works quite well. It doesn't have to be deep, but needs a slight grade to carry away the water. My trench varies in depth between 1 foot deep to 3 1/2 feet deep. The depth varies so as to maintain a 1% grade over the contours of my yard.

Leaving the stone uncovered is best, but you can cover the stone with landscape fabric and an inch or so of topsoil as you describe.

Vic

 

[Botabill]

I was hired to do a trench as you describe. I went down 3 feet and put in drainage pipe in the bottom covered to the surface with drain rock (crushed stone) . I also put in landscape fabric about a foot under the surface to minimize silt from working down and plugging the drain pipe holes. We had a huge rain storm when I was just about done and the home owner was excited as it was the first time she hadn't had water in the basement. The key is to have enough of a slope to take the water in the drain pipe somewhere away from the house.

 

[Lineman North Florida]

Thanks for the info guys, after talking to a couple of people today they told me that my ditch really did'nt need to be as deep or as wide as what I had thought, they seemed to think a couple of inches of gravel in the bottom of the trench then drain pipe holes facing down then gravel to within about 6 to 8" from the top followed by landscape fabric then topsoil, my trench is going to have to be about 60 to 70' long and the suggestions I got were to make it about 8" wide and no more than a couple of feet deep allowing about 2 to 3 inches of fall over the length of the ditch, sound about right?

 

[2manyrocks]

No, that's not the best practice especially if you have sandy soil. You need to trench to have a pitch towards wherever you want the water to end up. Then you put the landscape fabric in the trench leaving your self enough fabric to completely wrap around the pipe and the gravel you're going to install in the trench. Add a layer of gravel then your pipe --drainholes down. Add more rock around the sides and top of the pipe and then wrap the rest of the drain fabric around the rock and the pipe. Then backfill with your soil. The fabric is there to keep soil and sand out of the rock and pipe. Water will find its way into the rock/pipe and then drain out.

 

[2manyrocks]

No, that's not the best practice especially if you have sandy soil. You need to trench to have a pitch towards wherever you want the water to end up. Then you put the landscape fabric in the trench leaving your self enough fabric to completely wrap around the pipe and the gravel you're going to install in the trench. Add a layer of gravel then your pipe --drainholes down. Add more rock around the sides and top of the pipe and then wrap the rest of the drain fabric around the rock and the pipe. Then backfill with your soil. The fabric is there to keep soil and sand out of the rock and pipe. Water will find its way into the rock/pipe and then drain out.

Sounds like you would still have some issues with surface water so you may need to experiment with some grading to get the water headed into your trench area.

 

[Ken45101]

It depends on your soil. But if you still have the ground sloping toward the house, heavy rain will still run in that direction. Your ideal solution is to grade the land away from the house so that the water runs away from the house.

Is the current situation causing a problem?

 

[Dave5264]

From the original post, it sounded like a gutter/down spout spill problem, Would you not want to feed the down spout into the Trench/pipe to take it away from the house. If so, make sure the pipe in the trench can handle the rain load/volume from the gutters...how big is the roof, how many down spouts will feed it etc.

If this just run off from the rain water falling in the yard (vs the stuff pouring from Gutters and eves trough) the solution may not need to be as adept at handling sudden high volumes of water.

 

[Lineman North Florida]

From the original post, it sounded like a gutter/down spout spill problem, Would you not want to feed the down spout into the Trench/pipe to take it away from the house. If so, make sure the pipe in the trench can handle the rain load/volume from the gutters...how big is the roof, how many down spouts will feed it etc.

If this just run off from the rain water falling in the yard (vs the stuff pouring from Gutters and eves trough) the solution may not need to be as adept at handling sudden high volumes of water.

It is not a gutter problem as I have them on each end of the house and facing off to the side, so the water from the roof on the front of the house goes to each end of the house and run's off with the natural fall of the land , it is the water that comes down the natural slope of the land in front of my house that is causing the problem, hope I explained it better this time, sorry if I did'nt the first time.

 

[2manyrocks]

Next time it rains, get your umbrella and some marking flags. Go out and mark the areas where you need drainage. When it dries up, then you have an on the ground outline of what you need to address.

If you go on the Taunton Press Fine Homebuilding website and look under foundations and drainage, you will find lots of good examples of how to install your drain system. It will make good sense to you after you read an article or two.