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Everything You Need to Know About French Drains

Everything You Need to Know About French Drains

If you have a continuously wet area in your yard or water in your basement after a hard rain, there is a simple solution: install a French drain outside or within your home. It’s critical to have proper drainage in order to keep your home dry and mold-free. If you have groundwater pooling in your basement, it is not only an eyesore, but it may also create mold and rot in the wood.

Here’s a guide about French drains that will teach you all you need to know about them, such as what they are, how they operate, how to install them, how much they cost, and more.

What Is a French Drain System?

An outdoor French drain is a trench that is filled with rocks. It is linked to pipes that direct water away from your property. The elevated or higher end of a French drain is referred to as a drain field. Groundwater or extra surface water enters the drain pipes through the drain field. The second component is the French drain exit point, which is the lowest point where the water exits the drain.

If your basement is leaking through the foundation, a French drain pipe is the solution. Water pounds against the foundation in a “wet” basement, eventually pouring through. A French drain, on the other hand, redirects the water near the foundation and discharges it elsewhere.

If you still have water in your basement despite having proper outside drainage, you may need to install an inside French drain. You would cut a trench in your basement slab along the perimeter of the foundation, lay pipe in the trench, and install a sump pump to transfer the water out of your basement and to the outside.

A pipeless French drain is also an option. A pipeless French drain lacks a pipe and has higher internal resistance to water movement. As a result, it cannot evacuate as much surface water.

How Do French Drains Work?

Water will always seek the lowest place along the most direct path and will easily migrate in loose soil into empty pockets. That’s where a French drain comes into play. It forms a sunken channel and gives this accessible path, encouraging water to drain out of the surrounding soil and run along a smooth course.

To function properly, a French drain must use gravity to force water down from the surface of saturated soil, drawing it along the downward-sloping pipe to the right discharge point. You should slant the trench bottom about one inch every eight feet in the direction you want the water to flow. Depending on your specific situation, you can divert the water to:

  • A ditch for drainage
  • A low-lying area on your property
  • The street
  • A well that is dry

Look for spots where water pools, especially if the water is lying for hours or days after it rains, to determine where to install the French drain around your property.

How to Tell If the French Drain Is Working

Looking at your lawn or basement is the simplest way to verify if your French drain is working properly. If there’s water, there’s a risk there’s a problem and your drain isn’t functioning correctly. This problem could be caused by blockage.

When water seeps through the soil to reach the French drain, it frequently brings sediment with it, which it dumps on the gravel as it travels through the ditch. Over time, the sediment accumulates and inhibits the flow of water via the French drain. It may even completely obstruct it. When this happens, the water is unable to flow properly through the drain, causing homes and other property areas to flood.

Another way to tell if your French drain is working properly is to have it inspected by a professional. They can tell you whether there is any buildup that could cause a clog.

Advantages of French Drains

A French drain can be a blessing to your property or home. They have a number of advantages:

  1. Efficient drainage: One of the most significant advantages of a French drain is its capacity to divert water away from your home or foundation. With an interior or exterior French drain system, you can direct the flow of water where you want it to go. Whether you direct the water to a sump pump, a septic tank, or as part of a French drain system combo, a French drain keeps your basement dry and prevents foundation water damage.
  2. When compared to other basement waterproofing options, a French drain is surprisingly inexpensive.
  3. Transforms your lawn area: Instead of having a wet, soggy lawn, you can have a nice space for your children or pets to play.
  4. Fast: Installing a French drain is not difficult, and the process is quite rapid, depending on the intricacy and size of the French drain you require.

Disadvantages of French Drains

While there are various advantages to using French drains, there are also some disadvantages to using them that you should be aware of before installing one. Some disadvantages are as follows:

  1. Difficulty of installation: Installing a French drain pipe underground requires a great deal of skill, and there are various safety considerations. When a contractor performs french drain installation, then need to consider water supply lines, gas lines, and other underground utilities.  Installation may require the temporary removal of structures like walkways and porches, which could be hazardous labor. As a result, it is usually best to leave french drain installation to a professional.
  2. External pipe clogs: Even above-ground French pipes can become clogged, and this happens more frequently than underground ones. If the pipe clogs, you may find yourself with a flooded basement.
  3. Mud-related clogging: Soil erosion could be causing muddy water to enter the French drain, causing it to clog. While it is necessary to bury the drain sufficiently deep, the groundwater going through it may contain sediment that can accumulate. And, while at first the amount of this sediment won’t be too much, over time it can clog the drain.

What Does a French Drain Cost?

To avoid or repair flooding, you normally install a sump pump in the basement along with an inside French drain. These drains are located deeper in the ground. When a contractor handles the installation, it is time-consuming and labor-intensive, necessitating the excavation of a wide moat around your building’s base. You can expect to pay between $50 and $60 per linear foot.

If you have a 20′ x 30′ basement, you have a perimeter of 100 linear feet, which means the total installed cost may be between $5,000 and $6,000. If the perimeter of your basement is less than 130 to 150 linear feet and you only need a single sump pump, you could pay between $175 and $225. A larger basement normally requires the use of two sump pumps.

A contractor can install an outside French drain two to three feet underground to divert surface water away from your house and property. The drain length will be determined by how far away you want the water to be released. An outside “surface” French drain will typically cost between $10 and $15 per linear foot for all labor and parts, resulting in a total cost of $1,000 to $1,500.

French Drain Maintenance

Fortunately, frequent maintenance is not required for a French drain to function. However, garbage and leaves can accumulate in the drainpipe’s openings over time, reducing its efficacy. Clean out and snake the French drain once a year to avoid this.

An electric sewer snake is required for interior French drain maintenance, basement French drain clean-out, and outdoor French drain maintenance. If you don’t want to buy one, you can easily rent one. They are available for rent from hardware stores, home improvement centres, and tool rental establishments.

Snaking the Drain

Here’s how to snake and clean a French drain.

  1. Put on some strong leather gloves before you begin. As you feed the snake’s wire into the drain, the gloves prevent your hands from becoming torn up.
  2. Remove the drain’s cover. If the French drain is connected to a gutter downspout, you must disconnect the downspout from the drain’s entry point.
  3. Turn on the snake and insert the cable into the French drain.
  4. Hold the snake cable back as the snake turns in the pipe when it comes across an obstruction or a turn in the drain. Once it has passed through the turn in the drain or the obstacle, carefully feed it forward into the drain.
  5. Continue to run the cable into the drain until it reaches the opposite side. When the snake encounters resistance from tree roots, blockages, or other impediments, allow it to turn inside the drain.
  6. Retract the snake and feed it back into the device when finished.
  7. Spray water down the drain with a garden hose in power jet mode to push out debris or other obstacles.

Contact Kitchener Waterproofing for Your French Drain Needs

You can make an informed decision about installation, maintenance, and cleaning now that you know everything there is to know about French drains. Remember that even if your French drain is underground, it still needs to be inspected by a professional every two years. The same can be said of an inside French drain. Clogs and other unwelcome surprises, such as a flooded basement, can be avoided with proactive maintenance.

If it’s been more than a couple of years since you had your Kitchener home’s drainage assessed, make an appointment with Kitchener Waterproofing for a French drain examination. We provide French drain installation, cleaning, repair, and maintenance.

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Kitchener, ON, Canada

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