how do you build a french drain system

How to Install a French Drain

1. Call the 811 hotline to have underground utilities marked.
2. Dig the trench system.
3. Line the trench with landscape fabric. ...
4. Add 2 to 3 inches of gravel to the bottom of the trench.
5. Lay the drain pipe in the trench, with the drain holes facing down.
6. Cover the drain pipe with gravel to within 2 to 3 inches of the top of the trench.

Full Answer

Can I make a French drain without pipe?

Make the trench as deep as practical. Deeper trenches are more stable and present less danger of collapse during a heavy rain. This is especially important when you’re installing a French drain without a pipe. If your rain gutters cause drainage problems around your house, you can dig a ditch to connect the gutters to the main drainage ditch.

How to make a basement French drain?

Steps Download Article

1. Plot out and mark the path of the French drain. The drain should run about 1 foot (or 30 cm) away from the basement's exterior wall.
2. Dig out the floor of your basement along the path of the drain. ...
3. Grade the bottom of the trench. ...
4. Place the French drain piping into the trench with the perforations facing down.

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How to install a French drain in your landscaping?

Instructions

• Determine a Trench Location. Assess the flood-prone area (s) of your yard to determine a general location and route for your French drain.
• Gain Approval. Confirm that your yard drainage will not adversely impact anyone else's land or any public areas, which could lead to legal problems.
• Check the Slope. ...
• Dig the Trench. ...
• Line the Trench With Fabric. ...

How much gravel is needed for French drain?

You would need around 0.72 cubic feet of gravel per foot length of French drain for a typical French drain width of 10 inches and a depth of 12 inches if you’re using a 4″ drain pipe. How much gravel do I need for a 100ft French drain? The volume of the drain is the volume of the “box” that is 100 ft long by 6 inches by 18 inches.

How deep does a French drain need to be?

About 8 inches to 2 feet deepFrench 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, as well as the bases of retaining walls, may be deeper.

Does a French drain have to drain somewhere?

Ideally, as the excess water from one area runs down the drain, it will be distributed more evenly across your yard and absorbed. So water really doesn't need to be dumped anywhere, it just ends up in the soil along a better line of distribution.

Do you put gravel under pipe in French drain?

The grade should always slope away from the home to ensure that the water is directed away from the walls of the home. Cover the pipe with at least 12 inches of washed gravel. Lay filter fabric over the gravel to prevent any soil from clogging the pipe.

What material do you use for a French drain?

Industry standard for French drains are 4 to 6 oz non-woven drainage fabric. Avoid using socked wrapped perforated pipe alone without drainage fabric as it will easily clog with dirt/soil.

What can I do instead of a French drain?

5 Alternatives to French DrainsSump Pumps. A sump pump is one the the most popular and most effective alternatives to a french drain. ... Dry Wells. A dry well can add drainage without the need for an electrical or sewage line connection. ... Stairs, Steps or a Ramp. ... Landscaping. ... Valleys or Ditches. ... Gutters.

What is the average cost of a French drain?

between $500 and $18,000Average Cost of French Drain Installation A French drain can be a lifesaver for a home with water issues, but it doesn't come cheap: the average French drain cost is often between $500 and $18,000. Most homeowners pay somewhere around $5,000 to have a professional install a French drain in their yard.

Should I use landscape fabric in French drain?

The Bottom Line The best type of fabric for a drainage project such as a drain field or french drain is non-woven geotextile landscape fabric. If you're project requires high strength and also good drainage then a high end combination woven fabric could be suitable for your application.

Why do French drains fail?

Over time, a French drain may become clogged. Tiny soil and clay granules slip through the pores of the landscape fabric and gradually build up inside the pipe. Another common cause of French drain clogs is root intrusion from grass, shrubs, and trees.

How far should a French drain be from the house?

How Close Should a French Drain be to the House? A good rule of thumb is to install french drains 3 feet from the house. Make sure to measure around the porch, patio, basement and deck before installing the french drain system.

Can you cover French drain with dirt?

Can I cover a French drain with dirt? Because a French drain has holes throughout the pipe which allow it collect water, you should not install dirt on top of the drain pipe. Installing dirt will clog the pipe and the holes, rendering it useless.

How big should a French drain be?

four-inchPipe Size. According to foundation repair experts, a typical French drain system in a residential home has a four-inch diameter. But if the area experiences a high volume of water, it might be suitable to install six or eight-inch pipes.

How much gravel do I need for a 50 foot French drain?

How much gravel do I need for a 50 foot French drain? To calculate gravel needed for a 50′ french drain, multiply the length of the trench by the width and depth. If you plan to lay down 4 inches of gravel, multiply 50 feet x 4 inches = 200 cubic feet.

How far should a French drain be from the house?

How Close Should a French Drain be to the House? A good rule of thumb is to install french drains 3 feet from the house. Make sure to measure around the porch, patio, basement and deck before installing the french drain system.

Can you run a French drain to the street?

Your French drain should end where it is most appropriate to deposit excess sprinkler system water and rain water it carries. Most often, French drainage systems are installed to carry water towards the front of a house near the sidewalk or out into the road if you are able to cut through the curb.

Where do you start a French drain?

The topsoil is usually piled on the side opposite the subsoil since it will be spread back over the top of the trench. Often it is best to start digging at the farthest end of the drainage system, usually a ditch, the street, a drywell, or other low or dry area you are draining to.

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

Aside from what we've listed here, the difference between a French drain and a trench drain is that a French drain is used for water that is underground while a trench drain diverts excess water from a surface.

How far should a French drain be from the ground?

When burying the drainage pipe for a French drainage system in gravel, there should be about five inches from the top of the gravel to the surface of the ground. From: Brian Patrick Flynn.

What to do with drainage pipes in garden?

Bury drainage pipes with rocks in garden settings.

How deep should a trench be for spray paint?

Referring to spray paint marks, use shovel to dig a 6" wide trench with a depth no greater than that of the nearest foundation (Image 1). Tip: Proper trenches run parallel to buildings and horizontally across slopes. Once trench is dug, add a 3" layer of gravel along bottom (Image 2).

What to do after securing drainage pipe?

After securing the drainage pipe in the trench and adding a layer of sand, add a layer of topsoil for extra weight.

What causes water to leak in basement?

If you're having problems with standing water in your yard or a leaky basement, improper drainage is the culprit. Fix your water drainage issues once and for all by adding a French drain in just a few short steps.

How to hide the end of a drainage ditch?

Hide the end of a drainage ditch with attractive pebbles.

How to reroute water in yard?

Locate the appropriate area of yard for excess water to be re-routed. Choose a location where the flow of water won't affect neighboring properties. Determine a slightly downward-sloping route at least 1 meter from walls or fencing that's clear of any obstructions such as posts, trees or shrubs. Tip: Drains that slope 6" for every 50 feet ensure the best result. Use striping spray paint to mark drainage route.

How deep should a French drain be?

You want the trench to be at least 8″ deep. We would suggest digging it at least 8″ wide as well. A wider trench will allow the trench to last longer because it won’t collapse. It also allows more room for water to pass down because, again, the point of a French drain is to get water from a wet area to a dry area.

What is the purpose of a French drain?

The purpose is to take water from wet areas and disperse it into dry areas.

What are French drains and drywells?

A French drain is a trench dug in the ground into which a perforated tube is placed, and which is then filled with gravel or lose rocks. The purpose is to take water from wet areas and disperse it into dry areas. The loose gravel and perforated tubing help facilitate that water movement. Swampy areas in a yard occur because there is too much water there, so moving the water away and spreading it out corrects that problem. You can read about how to build them correctly below.

What are the drainage issues in turf?

There are three main kinds of drainage issues that occur in turf areas: water accumulating into a small lake, swampy type of ground, or a small flowing river.

How to stop roots from getting into drain?

When you’re finished digging, line the inside of the trench with landscape fabric that allows water to pass through. The fabric will help prevent some roots from getting into the drain and interfering with the water flow. It also holds back the soil from encroaching into the gravel.

What are the components of a drainage system?

A drainage system can have many different components including a French drain, drywell, closed tubing, catch basins, and pop-up emitters . In this blog post, We’ll be discussing French drains and drywells and how to install them correctly.

How to get rainwater out of a house?

One method is to build up dirt near the house to angle the water away. Another method is to install catch basins and solid tubing. A catch basin is installed to collect all of the rainwater from the downspouts, which is then connected to solid tubing.

How does a French drain work?

When adding an interior french drain a channel is chipped out of the concrete along the perimeter of the basement floor. Perforated pipe is then placed within the channel which will direct the water to a collection tank within the floor. A sump pump pushes the water out of the basement and into a nearby storm drain.

What is a French Drain?

The basic concept behind a french drain is that water flows downhill and follows the path of least resistance. Pretty simple, right? Actually, the implementation is a bit more complex. However, when the job is finished, it's simply a pipe within a sloped trench, filled with gravel that moves water away from your home's foundation.

What type of drains protect basements from flooding?

There are 2 types of french drains that can directly protect your basement from flooding. The deep french drain and the interior french drain. Let's take a closer look at each:

What is the second type of French drain?

The second type is an Interior French Drain where the water is collected as it enters your basement. This is typically a better option than Exterior French Drains since they have an excellent track record of keeping basements dry.

Why does my basement leak?

Many basements leak because of standing water that pools around the home's yard. A traditional French drain can move the water away from the house. Installing this type of French drain is relatively easy and cost effective. Before starting, you should always check for utility lines and underground pipes.

How far should a drain slope?

The best performing drains are those that slope roughly 6 inches for every 50 feet.

What is the best way to plan a trench?

Landscaping spray paint is an excellent way to plan your trench. Simply spray the path your trench will take and you'll have an excellent visual of where you'll be working.

What is a French drain?

A French drain, also called a curtain drain, is made by placing a perforated pipe in a trench that has been filled with gravel. It is a great option if you want to direct surface water away from your home’s foundation to remove surface water or to prevent flooding. [2]

How to get rid of a drain?

The spot will need to be downhill enough for the water to run away from the problem area. In general, the drain will need to have a 1-2 percent s lope drop for every 100 feet (30 m) of length.

How to dig a trench on a slope?

Use a shovel to dig the trench across the slope. Start at the top of the trench and dig your way down. Check the grading regularly as you dig to ensure you are creating the right dimensions. You may find this process easier if you ask friends or family to help you dig, especially if you are digging a long trench.

Why is a drain pipe too wide?

Pipe that is too wide can take up too much space in the trench and allow debris to get into the drain.

How wide should a trench be?

Pick a spot that is 5 to 6 inches (13 to 15 cm) wide. Make sure there is enough available ground at the location so you can put in a trench this wide. The trench does not need to be wider than 6 inches (15.2 cm), as you do not want to make it too wide.

How to measure pipe for a trench?

Measure the location to get the right amount of pipe. Use a measuring tape to determine how long the pipe is going to be in the trench. Start at the beginning of the trench and measure down to the bottom of the trench. You may want to add a few extra inches to the measurement so you have more than enough pipe.

How to keep fabric in place?

Place a thin layer of gravel over the fabric to keep it in place. Spread a light load of gravel with a shovel over the top of the fabric. This will help the corners of the fabric warp around the gravel, securing it in place.

How deep should a French drain be?

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. Washed drainage gravel (figure the amount needed with a gravel calculator) Water-permeable landscape fabric to prevent silt and roots from entering the drain pipe.

How to move dirt off a trench?

Tip: A trenching tool throws dirt off to the side. Lay pieces of old plywood or a heavy tarp alongside your trench location to catch dirt and make it easier to move it to another location.

How do French drains work?

Counterintuitive though it may be, French drains work by allowing water to flow into them from below. Wrap landscaping fabric around the pipe to keep dirt and roots from obstructing the system.

WHAT IS A FRENCH DRAIN?

It sounds elegant but in reality, it’s nothing more sophisticated than a gravel-lined ditch with an embedded pipe that carries water away from the home.

What is the difference between PVC and flexible drain pipe?

PVC lasts longer, and if you encounter a clog, it can be cleaned with pressure or a plumber’s snake. Flexible pipe , on the other hand, is less expensive and easier to work with. Advertisement.

How deep should a French drain be?

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. If you’re installing a French drain around your foundation to prevent basement moisture, take care to position the pipe below slab or finished floor level.

Can you wrap a pipe with landscaping fabric?

Instead of wrapping pipe with landscaping fabric, you can buy a flexible perforated pipe that comes encased in water-permeable fabric.