How far down should a French drain go?

Jim Brown August 15, 2021 Helpful tips

Contents

1 How far down should a French drain go?
2 What is the difference between a French drain and a curtain drain?
3 Is the hole in a French drain pipe up or down?
4 What do you need to know about a French drain?

How far down should a French drain go?

about 18 inches
The trench should be about 18 inches deep and 9 to 12 inches wide. French drains need to have a slope of at least 1 percent, so the force of gravity will work for you. This means that the drain should slope down a total of at least one inch for every 10 feet of pipe.

What is the difference between a French drain and a curtain drain?

Curtain drains essentially do the same thing that french drains do- get rid of the water. The main difference is that french drains deal more with groundwater while curtain drains have more to do with surface water. Curtain drains are built in a very similar way to french drains but are dug to a shallow depth.

Do I really need a French drain?

Why French Drains are Necessary If you are a homeowner with a wet basement or a moisture-laden yard, you can likely benefit from a French drain. Any issues with surface water along your property should also spur the installation of a French drain. If your driveway washes out, it is a clear sign you need a French drain.

What’s the best rock for a French drain?

Hard rocks such as granite or river gravel prove viable options for a French drain because they won’t break down over time as much as other rock varieties, such as sandstone and limestone.

Is the hole in a French drain pipe up or down?

Generally, the holes for French drains should be pointing down, or at least oriented in a downward direction. This is counter-intuitive, as people think this will cause the water to drain out of the pipe, rather than into it. However, in order for a French drain to function properly,…

What do you need to know about a French drain?

Most descriptions of a french drain involve a slotted or perforated pipe, a trench, geotextile fabric and gravel backfill. To operate properly, the drain must have adequate slope and a place to open onto the ground, into a drain pipe or somewhere else where water can exit.

How big are the perforations in the French drain?

French drain installation in median of two lane each dual carriageway super-elevated section. Approximately 1.8m deep, 600 wide, surrounded with geotextile. We are installing a 150mm diameter perforated pipe within the French drain. Perforations of 8mm diameter; 4 rows of holes all in same half section of pipe.

Is it better to have a hole up or down in a drain pipe?

Either way, though, when silt and debris fill the pipe to the level of the perforations—essentially half the diameter of the pipe—it can no longer take on water and no longer is effective for drainage. So there are good arguments for both methods. Having the holes facing up is just the most effective plan for the systems that I’ve designed.

How far down should a French drain go?

Jim Brown September 21, 2019 Contributing

Contents

1 How far down should a French drain go?
2 How deep and wide for a French drain?
3 What should the depth of a French drain be?
4 Where do I put a French drain in my basement?
5 How big of a trench do you need for a drain pipe?

How far down should a French drain go?

How deep and wide for a French drain?

Parts of a French Drain A trench at least 12 inches wide and 18 to 24 inches deep; larger trenches provide better drainage and last longer, but require more work.

Do French drains add value to your home?

A French drain is a trench that slopes away from your home to divert water to other areas where it cannot cause as much damage. French drains can also add value to your home, which is a huge bonus if you know you are planning to put it on the market in the future.

What should the depth of a French drain be?

Other elements to consider include: French drain depth: About 8 inches to 2 feet deep should be sufficient for many water-diverting projects, though related systems, such as those built around foundations and sub-ground living spaces]

Where do I put a French drain in my basement?

You’d cut a trench in your basement slab along the foundation’s perimeter, lay pipe in the trench and put in a sump pump to move the water out of your basement and to the outdoors. There is also the option of a pipeless French drain.

What kind of pipe does a French drain use?

French drains and pipeless French drains can require a lot of effort with only marginal effectiveness for many reasons. Most descriptions of a french drain involve a slotted or perforated pipe, a trench, geotextile fabric and gravel backfill.

How big of a trench do you need for a drain pipe?

Because there is a direct relationship between the diameter of a drain pipe and its relative effectiveness, make your trench no smaller than 12 inches wide, and aim for a depth between 18 and 24 inches.