Drain pipes in the soil beneath your French drains can become clogged and block drainage, causing water to back up into your crawl space or house. In some cases, soil expansion in your yard and driveway can cause drainage problems in your French drains. In most cases, the drain pipes in your French drains are installed to protect your basement floor from sewer backing up into your crawl space or house. A French drain is simply a trench filled of rock or gravel or containing a perforated drain pipe that directs surface water away from an underground area.
When a French drain becomes plugged, it’s referred to as an underground fill. It can occur when the French drain gets full and can either be caused by excess soil pushing against it or expanding on the inside of the trench. It can also occur when ground leveling is poor, especially if the French drains are located above a slope. Most often, underground fill problems occur when the French drain contractor isn’t doing a good job of grading the area where he wants to install the French drains. Asphalt or clay in the area can easily compact over time and create a perfect environment for roots to grow.
If you’ve had to excavate your foundation, you know that it isn’t always an easy job. Digging around the walls, piling up concrete slabs, and setting the walls up on ladders can make digging a French drain installation very difficult, if not impossible. On top of all that, if the excavator isn’t doing a professional job, it can be very expensive to repair damages that have occurred while digging. It’s much better to let a qualified foundation contractor do his job, and provide you with a concrete ditch that will cut down on future problems with French drains.
When you’re considering all of the variables involved in installing French drains, you need to ask yourself whether it’s more important to dig straight down, or to allow some flexibility for soil expansion. With traditional drainage systems, you have the option of excavating a depression and then planting your French drains right down to the soil. With flexible French drains, you may be able to plant your landscape fabric in a position that will allow you to excavate and then plant at the bottom of the excavation.
If you have a basement, there is a good chance that you have a wet basement. If you’re going to install French drains in your basement, you want to make sure that you don’t dig too deeply, since you will be introducing root systems into the basement which can be quite expensive to remove later. However, if you have a wet basement you can still install French drains, but you’ll need to excavate a little bit deeper and make sure that you have the proper drainage installed before you do.
In addition to the considerations mentioned above, there are also many other factors involved when it comes to basement waterproofing and French drains. One of the biggest considerations is soil resistance, since French drains are generally wider and heavier than normal PVC pipes, and thus require a different approach to drainage problems in the area. One thing to keep in mind is that soil density also plays an important role in the life of French drains, as well as the amount of time it takes for them to drain all the way out of a basement. If soil is packed or compacted in any way, French drains can be a problem, since digging around to remove them can be difficult, and even impossible, especially if the basement has suffered heavy water damage.
A final consideration of drainage problems in basements is the thickness of the mesh or fabric on French drains. If you install French drains with mesh that is too thin, the pooling of water below the surface can cause problems, especially if it penetrates through the concrete or underlying structure of the building. The presence of water in a basement absolutely ruins the chances of you ever being able to waterproof a basement properly, and this is why you must choose the right materials and get French drains installed by a professional. The fabric thickness of French drains can range from one and a half inches to three inches, with some models capable of three inches of mesh. The thickness of the mesh can affect both how quickly the water drains and how effectively the drain system actually works. If you have any doubts about the strength of your French drains, then you should consider getting a professional to check it out for you.
French drains aren’t all about the size and installation. A major factor that affects how well your French drains function is the amount of grit on the surface of the mesh – this plays a big part in how fast the water drains, how effective the drainage system is, and how safe your basement environment is. The most ideal French drains will feature a large mesh area of between one and two inches, with the grout being between six and eight inches deep. If you have a smaller floor space, or if you need to hide the drainage pipes beneath the carpet, then a more shallow grate with a single, larger mesh will be adequate.