What is a French Drain?

With a name like a French drain, you may be thinking of croissants and Beaujolais. But, no. French drains are actually American. They were popularized by Henry Flagg French in the mid-1800s.

A French drain uses gravity to move water away from your foundation, lawn, retaining wall or any other soggy area and takes the water somewhere else – the street, the gutter, a nearby pond, etc.

Unlike other drains with obvious grates and catch basins, French drains are nearly invisible. It just looks like a small gravel path and can easily be incorporated into your landscaping. In fact, you’ve probably driven past dozens of French drains and have never even known it!

Why should I install a French drain near my foundation in Los Angeles?

A French drain is your home’s best friend during the rainy season. We all know that the rainy season in LA sees huge amounts of water being dumped on the landscape in a short amount of time. A French drain can help avoid flooding, soil erosion and structural problems that are caused by too much moisture. French drains are especially useful for hilly properties where water builds up near your home’s base. 

What happens if you don’t install a drainage system? Believe me, you do not want water pooling around your foundation. It can cause cracks or even shift your foundation. Water also is a driving force in soil erosion, which can lead to your house “settling” and causing even more cracks in the building. 

Installing a French drain usually runs from about $4,000 to $13,000 depending on the size of the job. That may seem like a hefty amount. But, believe me, a cracked or shifting foundation is FAR more expensive to fix. It’s much better not to have a water issue in the first place. 

How does a French drain work?

French drains depend on gravity to move water into a pipe, which then moves the water away from one place to another. It’s actually a pretty ingenious design.

Basically, a small trench about 12 inches wide and 18 inches deep next to your home. The trench is dug at an incline of 1%. What does that mean? That means, the incline moves down one inch for every 10 feet. Then, a layer of gravel is placed on the bottom of the trench and then a permeable pipe is placed on top of that with a piece of fabric on top. Then, the pipe is covered with gravel.

So, how does it work? Water in the soil seeps into the pipe, with the fabric keeping out dirt and rocks. Once the water is in the pipe, it will move away from your foundation. 

Once installed, you can expect your French drain to last for about 30 to 40 years. Plus, it’s very easy to maintain. About one a year, put a hose in it and turn on the water. If the water backs up, then use a sewer snake or a pressure hose to blast any debris that has built up. As soon as water runs freely through the pipe, your French drain is ready for another soggy season.

How can I install a French drain?

As with most home improvement projects, the first thing you should do is call a licensed contractor.

Sure, you can find all kinds of videos on YouTube on how to DIY install a French drain. So, you could, in theory, install a French drain on your own. But first, ask yourself, do you have the equipment to dig a trench? Are you going to dig it out yourself? Who is going to dig this trench? Do you know how to dig a 1% incline? How long will it even take for you to do the project yourself? We all know at least one DIYer whose home is filled with unfinished projects. This is one project you don’t want to leave half-done.

Do yourself a favor. Hire a licensed contractor to install your French drain. It will be much easier and quicker and you’ll be saving yourself from many headaches. A licensed contractor has all the equipment, manpower, and know-how to install a French drain quickly and correctly. In fact, it will probably only take a couple of days to install!

Ready to install a French drain? Give us a call and let an experienced contractor take care of the job.