They keep surface water away from your home. Interior French drains tend to be less expensive than exterior ones mainly because they avoid the costs of extensive excavation, landscaping, and potentially dealing with obstacles like driveways or patios.
Clogging. A French drain pipe that's clogged with silt, sediment and other debris can clog and cause water to overflow or backup into the basement.
French drains help prevent flooding and reduce the risk of long-term water damage to your property. They can last between 30 and 40 years.
Agree. Outside is best, but typically difficult/expensive. Inside is easier and cheaper. Most waterproofing contractors are going to try to sell the interior solution because it works (but not as well), is more affordable to the homeowner, and has higher margins than doing it externally.
Installing a small French drain usually doesn't require a permit. If your drain will be diverting water into a municipal drain or sewer or your property has a shallow water table, you may need a building permit. A professional French drain installer will take care of getting any permits the project needs.
French 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.
Clay soil has poor permeability, meaning it doesn't allow water to pass through easily. In such cases, the effectiveness of a French drain may be limited as the water may struggle to drain away from the area efficiently. French drains may not be suitable for areas with high water tables.
Swales: A Natural Solution
They're a great option if you're looking for a more natural, eco-friendly alternative to French drains. A swale is typically lined with grass or vegetation that helps slow down and absorb water.
An interior French Drain is a trench providing a channel for the water to flow through and into a sump pump basin. The trench is filled with gravel as well as perforated pipe, in which the water runs freely and then empties at a safe distance from your home.
With stormwater, most likely, your drainage systems would fall under land improvements. Stormwater best management practices such as french drains, downspouts and gutter systems, bioswales, and dry wells could qualify as depreciable assets.
Moisture and mold: The soil surrounding the pipes and gravel installed under the concrete is always wet. Wet soil will grow mold. The mold spores, odor and evaporating moisture will travel into the house through the opening in the french drain system.
By preventing water damage and maintaining a healthy landscape, French drains can reduce long-term maintenance costs. This is a valuable selling point for potential buyers, making your property more attractive and potentially increasing its resale value.
French drains are best suited for properties with moderate to severe water drainage issues, particularly in areas with heavy rain or poor soil drainage.
If you put the drain in the wrong place, the water could end up pooling in landscaping or around your home, leading to leaks and foundation damage.
French drain installation is a service offered by a diverse range of professionals from landscapers to plumbers to foundation specialists. These professionals bring a varied skill set to the project, often integrating the drainage system seamlessly with other landscaping or construction work.
Interior French drains are meant for waterproofing the basement or draining your crawl space. They cost more because contractors must tear out the basement floor (most often made of concrete), install the drain, and then repair it.
1. Trench Drain. Although they rhyme with French drains, trench drains prevent surface water from pooling in unwanted areas, like driveways and patios.
Just like other types of drains, they are susceptible to clogging over time. Ideally, clean the French drain once every year.
Clogging and Blockages
Clogging is one of the leading causes of French drain failure, often due to root intrusion or sediment build-up.
It's a drainpipe installed in the ground and pitched in the direction you want the water to flow. They can be installed inside your basement or outside your home and may or may not be attached to a sump pump. If installed properly a French drain is as effective as it is simple.
French drains (aka weeping tile, perimeter drains, agricultural drains, and rock drains) are an easy-to-install solution for your drainage problems. Clients pay an average price of $5,000 to have a French drain installed professionally, with most homeowners paying $1,650 – $12,250.
A French drain installed either inside, under your basement floor, or outside, buried along the foundation footer, prevents hydrostatic pressure from building up by making sure the soil never gets saturated. All excess water is channeled away from the foundation, either via gravity or by using a sump pump.