How much gravel should be in the bottom of a French drain?

Pour and compact about 3 inches of gravel or landscaping stone along the bottom of the trench. This will act as bedding for the drainage piping.

Do French drains require gravel?

The old way of installing French drains is to do it without the gravel and the fabric. Without the gravel and the fabric, however, the drain can clog up with sand and soil over time.

What kind of gravel do I need for a French drain?

The stone should be no less than ¾” and dense (we suggest Granite, or River Gravel) so it will allow good water flow. Lime Rock, although inexpensive, is a poor choice for a French Drain because it will begin to deteriorate over time and eventually begin to pack down and restrict flow.

What should you be charge per foot for French drain?

French drain costs $10 to $50 per linear foot or between $500 and $10,000 in exterior and perimeter applications and $40 to $100 per linear foot or $1,000 to $18,000 for internal ones. These systems can benefit your home in a variety of ways.

How deep should you bury a French drain?

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.

How many years does a French drain last?

approximately 30 to 40 years
Generally speaking, a French drain will last approximately 30 to 40 years. However, the above-mentioned factors may shorten its life cycle and it must then be replaced by a team of foundation experts.

How to calculate how much gravel you need for a French drain?

Multiply the length (L), in feet, by the width (W), in feet, by the height (H), in feet, and divide by 27. This will tell you how many cubic yards of crushed stone you need. Regarding this, how much gravel do I need calculator?

How big does a French drain have to be?

French drains are an effective way to remove excess water. French drains are a low-technology solution to divert excess water away from a building and allow it to soak into the ground. They typically consist of a trench up to 2 feet in width and depth, with a perforated pipe surrounded by gravel or small stones.

Why does water stick to gravel in French drain?

In much the same manner, rainfall sticks to itself and to the surface of soil, gravel, sand or whatever other surface with which it comes into contact. Water would rather stick to something than simply fill a void. Thus, water usually sticks to the gravel in a French drain rather than filling the voids.

How do you slope a French drain pipe?

The drainage pipe (or drain tile as some call it) will lay on a bed of gravel in the bottom of the trench and it is very easy to move this gravel around to properly slope the drain pipe. So back to the stakes and strings.

How to dig a trench for a French drain?

1 Check for underground utility lines and pipes before digging. 2 The trench should be about 18 inches deep and 9 to 12 inches wide. 3 French drains need to have a slope of at least 1 percent, so the force of gravity will work for you. 4 Depending on the size of your trench, either dig the trench with shovels or rent a trencher.

How much does a French drain grating cost?

At $6.70–$10 per linear foot, grating costs $67–$100 for a 100-foot drain. Exterior French drains are most effective when they slope away from your property — landscapers recommend a drop of one inch for every 10 feet.