How Much Does a French Drain Cost?

What Is a French Drain?

A French drain is a trench filled with pea gravel and a perforated pipe at its center that you typically install in the basement or yard. Its primary purpose is to divert standing or pooling water in areas where you have issues with flooding. The cost to remove standing water is $3,500 on average, but you can recoup your French drain installation cost with as little as two avoided water backups. 

French drain is a generic term that can refer to a number of drainage solutions; you might hear contractors use other terms like "weeping tile," "channel drain," and "trench drain" when discussing your French drain installation. The variation in names often refers to how and where it's installed. For example:

• Weeping tile drain, perimeter drain, footing drain, drain tile, deep French drain, and foundation drain: Laid at the foundation level around the exterior or interior

• Curtain drain: Laid at or near the soil surface around the home exterior to divert surface water (rain and snow) rather than groundwater

• Trench drain, yard drain, or garden drain: Typically a surface-level style used in yards, driveways, and gardens

French Drain Cost per Foot

French drain installation cost per foot varies depending on the type of French drain. On a broad scale, expect to pay $10 to $100 per linear foot.

The table below breaks down French drain cost per foot by the type (and thus location) of the drain:

Interior French Drain Cost

An interior French drain can cost anywhere from $2,000 to $18,000. Whether it’s installed in the basement or crawl space—and if project costs also include the installation of a sump pump—will affect your total French drain installation cost.

Interior Perimeter or Basement French Drain Cost

Interior basement French drains cost around $40 to $100 per linear foot or $4,000 to $15,000 on average, though installation prices may go as high as $18,000. Most basements need 100 to 150 linear feet of drain.

Basement foundation drains, also called drain tiles or perimeter drains, require more work and materials since contractors need to install the drain pipe under the concrete. These basement French drains often need specialized membranes for drainage.

It’s important to install a basement drain correctly to ensure minimal repairs are needed down the line. On average, basement drain repair costs $3,230.

Crawl Space French Drainage System Cost

Installing a French drain in a crawl space costs about half as much as the total basement French drain, or roughly $2,000 to $7,500. Unfinished crawl spaces might be slightly less expensive.

If you have a damp crawl space, you might want to budget for crawl space encapsulation costs. Encapsulation helps reduce moisture accumulation, which can be detrimental not just to the French drain but also to your home.

Cost to Install a Sump Pump and French Drain

Installing a sump pump and a French drain in your basement costs around $4,650 to $17,000. Alone, sump pump installation costs approximately $650 to $2,000. You don’t always need both installed at the same time, but they’re often put in together.

The two work in tandem to prevent water backup. The drain tile or perforated pipe of the French drain allows perimeter water to end up in the sump basin, set lower than the tile. The sump pump then sends it outside your home to a storm drain or your internal sewage outlet where allowed.

“When using a sump pump in conjunction with an interior French drain, it’s a good idea to install a battery backup for the pump's power supply,” says Jeff Botelho, Angi Expert Review Board member and Massachusetts-licensed journeyman plumber.

Exterior Perimeter Weeping Tile Drain Cost

Exterior perimeter weeping tiles and French drains cost around $1,000 to $10,000 or more, depending on the depth you dig to and the size of your home’s footprint. In general, budget for $10 to $50 per linear foot.

A 4,000-square-foot single-story ranch-style home may need 200 linear feet, while a 2,000-square-foot three-story brick home may only need 120 linear feet or less. Perimeter drains sometimes run on both the exterior and interior of a house.

There are a few notes to remember about exterior perimeter drains:

• The international building code requires the installation of perimeter drains on all new homes where natural drainage doesn’t occur.

• They run along the perimeter of the home at the level of the footings.

• They’re easy to install during building but more difficult and costly after the fact.

• They’re also known as deep French drains, footing drains, or weeping tile systems.

Curtain Drain Cost

Curtain drains cost around $1,000 to $5,000, or about $10 to $25 per linear foot. They’re usually 2 feet in the ground against the foundation. This perimeter-style French drain slopes away from the foundation. Unlike deep drains, these only divert surface water like rain and roof runoff. On the other hand, deep French drains can also handle groundwater.

Cost to Install a French Drain in the Yard

French drains in yards run around $10 to $35 per linear foot and are typically installed to drain off standing water. You might also attach them to buried downspouts or a perimeter drain to move water away from your foundation.

The expenses include:

• Piping: $50–$300

• Gravel: $100–$400

• Labor: $50–$100 per hour for landscapers; $45–$200 per hour for plumbers

• Trenching equipment rental rates: $100–$200 per day

French Drain Installation Cost Breakdown

The total price to install a French drain boils down to labor and materials. Depending on the project, labor costs can include plumbers, landscapers, and even concrete specialists. Material costs include the actual piping for the drain, plus equipment, gravel, and a couple of optional materials.

Labor

Labor for French drain installation can range from $50 to $200 per hour, depending on the type of contractor you need. Most of your cost comes from labor since the pipe and equipment cost little in comparison.

• Plumbers cost $45–$200 per hour, depending on the experience level.

• Professional landscapers charge $50–$100 per hour to dig the trench to install your drain in the yard.

• Basement French drains require more labor since your pro needs to demolish the concrete around the perimeter to install the drain, flashing, and waterproof membrane. Then, they’ll need to redo the concrete. Concrete removal costs from $4.75–$7.50 per linear foot for a 4-inch slab, plus the cost of pouring replacement concrete.

Materials

Perforated drainage piping costs around $0.50 to $3 per linear foot. You'll also need to buy a dirt cloth or pipe with a cloth membrane called a sock. The sock keeps small pieces of dirt out of the pipe, preventing it from clogging.

The table below looks at typical material costs for a French drain installation:

French Drain Installation Cost Factors

In addition to the location of the pipe and the type of labor required, you’ll need to factor in additional French drain installation cost factors, including accessibility, length and depth, and landscape repair.

Accessibility

In general, interior French drain installation is more expensive because contractors have to remove a section of concrete. However, costs can go up inside or outside depending on the accessibility. For example, if your land has rocky soil, it may take landscapers longer to dig the trench for an outdoor French drain. The resulting cost will reflect that added labor.

Length and Depth

The longer the perimeter drain, the more expensive it'll be to install—largely due to increased material prices. If the contractor needs to dig deeper to install the pipe, you'll also see costs go up due to increased labor costs. This is why shallow French or curtain drains are typically less costly than deep French drains.

Landscape Repair

Installing a French drain in your yard means contractors may have to rip up your lawn or garden. Their costs don’t include repairing the landscape after installation. If you’re unable to handle the landscaping yourself, you’ll need to budget for the following potential costs:

• Lawn seeding cost: $90–$180 for up to 1,000 square feet

• Sod installation cost: $1–$2 per square foot

• Landscape installation cost: $25–$50 per plant; $300 for a simple flower bed

Signs You Need a French Drain

Here are some basic signs to look out for if you think you need a French drain:

• Soggy yard: If your yard regularly pools or gets mushy after it rains, you may need to install a French drain to help with drainage.

• Basement flooding: A French drain might be a good investment if your basement regularly floods during storms. Even minor basement flooding typically points to the need for a drain.

• Retaining wall damage: If your home sits on a hill with a retaining wall, runoff can damage the stone over time and even threaten its structural integrity. If you notice damage to your retaining wall, a French drain may help reroute water where you want it.

• Wet climate: Even if you aren't regularly seeing signs of flooding, living in an area with a lot of rain is reason enough to be proactive.

French drains aren’t the only solution to flooding problems. Talk to a professional contractor about the cost to install drainage systems and which solution makes sense for your home.

DIY vs. Hire a French Drain Installer

Hire a pro to install a French drain, especially those around your basement or perimeter. As with any digging, you might run into buried utility, sewer, or drain lines. You also need to understand how water gets into your basement and how it drains away. Cutting lines or improper installation can cost you thousands in repair and replacement fees. Find a local French drain installer for quotes. 

In addition, each state (or in some cases, a collection of states) has its own programs that monitor underground utility services. The law requires you to contact Dig Safe/Call-Before-You-Dig at 811 before beginning any digging project. Call at least several days before your project is scheduled to start.

FAQs

How long do French drains last?

French drains last 30 to 40 years on average, and newer styles with cloth socks that keep the dirt out may last longer. Improper installation and clogs that go untended can shorten the life of a French drain, so it’s essential to monitor your drain’s performance and hire a plumber near you if you suspect a clog.

How deep do I need to dig a French drain?

You can install a French drain anywhere from 2 feet below ground level to the level of the footings of your foundation. Surface-level drains only divert water on the surface, like rain and snowmelt, while French drains buried deeper can divert groundwater. Inside, contractors will install interior perimeter drains beneath the concrete of a basement floor.

Are interior French drains effective?

Interior French drains are effective against flooding and water damage if you have a way to drain off the moisture and can keep the pipe from clogging. If the perimeter pipe does clog, it’s generally easy for a plumber to access it. Usually, you’ll want to combine an interior French drain with a sump pump for maximum effectiveness.