# How Do You Calculate Gravel For Drainage?

## What gravel do you use for drainage?

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..

## How do you calculate gravel for a trench?

How much gravel do I need?Determine the length and width of a cuboidal excavation. … Calculate the area of the excavation, multiplying the length and width together. … Determine the depth of the excavation. … Multiply the area and depth of the excavation to obtain its volume: 18 * 2 = 36 yd³ .More items…

## How much gravel do I need to fill a trench?

Multiply the total number of inches for the gravel depth by the total square feet from the previous step. For example, using a gravel depth of 3 inches, convert the inches to feet, which equals 0.25. Multiply 120 square feet by a gravel depth of 0.25 feet to equal a volume of 30 cubic feet.

## Is crushed gravel good for drainage?

If you have an area of your yard where the water doesn’t drain the way you would like, add some crushed stone as a decorative feature. The stone will help the water drain and not puddle while providing some decoration.

## Can I use pea gravel for drainage?

Since it has a smooth finish, pea gravel is also regularly used for walkways, dog runs, playgrounds, patios, and a variety of other high-traffic areas. Like crushed stone, pea gravel can also be used for underground projects, such as drainage and pipe bedding.

## What is the best size gravel for drainage?

½ inch to 1-inchIn general, you want to aim for ½ inch to 1-inch gravel for drainage. Areas that will see especially heavy flow may need larger gravel. Or, projects without drainage pipes may also need larger gravel. For example, a French drain without perforated pipe needs 1 ½ inch gravel.

## What does crushed gravel look like?

Color will vary depending on the type of rock from which it was made. Crushed gravel, on the other hand, is produced by the natural processes of weathering and erosion, and typically has a more rounded shape verses the angular surfaces of stone. … Color will vary from yellow and reddish hues to bluish and grayish hues.

## How much gravel is in a ton?

Using 2 inches for the depth, the following measurements are a guide to the amount of gravel coverage per ton: 1/4 to 1/2 inch gravel, 100 square feet per ton; 1/2 to 1 inch gravel, 90 square feet per ton; and 1 1/2 to 2 inches gravel, 80 square feet per ton.

## How do you calculate drainage of a rock?

In the construction world, most materials are measured in cubic yards. 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. When using this equation, make sure all of your measurements are in feet.

## What is the difference between gravel and crushed stone?

Gravel is a natural product of weathering and erosion. … Crushed stone usually has more angled surfaces than gravel as a result of the crushing process. Crushed stone can also range in size from fine dust to large rocks. Gravel is more rounded and often smaller than crushed stone.

## Does adding sand to soil help drainage?

Sand is one of the cheapest things you can add to your garden soil that will help to break up the soil. The small particle size of the sand will get in between soil clods and break them up, increase drainage, and help to aerate the soil for good root development.

## How many inches of gravel do I need for a French drain?

Gravel used for this layer is typically 1/2 inch to 1 inch across — the larger it is, the better the water flow and less chance of clogs and blockages. For a French drain without a perforated pipe, opt for even larger gravel, such as 1 1/2 inches across.

## Is sand or gravel better for drainage?

Water moves through gravel a lot faster than it does through the majority of soil and other materials. … It’s recommended to place down a few layers of crushed rock or sand underneath the gravel in order to stabilize the drainage surface.

## Is sand good for drainage?

Sand is useful for drainage. The lighter, coarser texture of the sand helps water move through the soil more quickly and can help a landscaper or homeowner prevent landscaping problems such as water standing in the yard. Use the proper mix of sand and soil to make your gardening efforts more successful.

## How much gravel do I need for drainage pipe?

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.