Dirt comes in many different types and varieties, each classified by the amount of certain compounds found within the soil. Fill dirt is one of the most commonly used dirt types, as its composition makes it ideal for many construction projects around a property.
Fill dirt can actually be classified in a few different ways based off of its contents. You can easily determine a particular portion of fill dirt’s makeup by performing a quick and easy “test.”
Before we get to that part however, it’s best to first explain what fill dirt is, and what it’s best used for.
What Classifies Dirt as Fill Dirt?
Fill dirt is a term that refers to dirt that is best used for filling. Makes sense, right? The actual source of fill dirt accounts for why this is so. Fill dirt is sometimes referred to as subsoil. This dirt is found beneath the very top level of soil (topsoil) and contains a vastly different composition.
While topsoil contains a high level of nutrients, carbon, and nitrogen, fill dirt is the opposite. Fill dirt contains very little organic matter and more solid particles that withstand breaking down or composting.
With topsoil, the dirt is constantly breaking down organic material, which leads to the release of gas, causing pockets to form and breakdown. This results in the soil shifting, and never really providing any kind of firm foundation. This is perfectly fine for topsoil, as its job is to cover subsoil while allowing vegetation to grow. This is not ideal for construction preparation, or when filling gaps and inconsistencies in a property’s landscape.
If you were to fill a large gap or hole with typical topsoil, you’d be setting up the area to fail, as the dirt will eventually shift and become uneven due to it breaking down. The soil may even sink, or cause a natural hole.
Fill dirt’s composition allows it to drain away water and maintain structural stability, since there’s little to no organic materials inside that can cause the soil to shift. Because of this, it’s best used when preparing a surface for construction, filling gaps and holes, and creating grading and slopes on a property for drainage purposes.
Simply put, fill dirt is the go-to dirt choice for any kind of construction or home improvement project that doesn’t involve planting anything on top of it. Although topsoil can always be added, fill dirt provides the basis of which everything else is built upon. Please visit our blog on the Different Ways to Use Fill Dirt for more information.
How to Identify Fill Dirt
Here is a simple way to analyze and identify the composition of fill dirt: all you need is a glass jar, and a little water and dish soap.
Begin by taking the jar and filling it about 2/3rds full of water and a teaspoon of dish soap. Add in fill dirt until you read about 1 inch from the top of the jar. Place the lid on the jar, and shake for around 30 seconds.
Set the jar to the side and allow it to settle for a few minutes, or until clear. The sand in the jar will fall to the bottom, while any silt will settle on top. You want a low amount of silt present, if any at all.
Clay will settle at the very top of the jar. While clay is often desired in fill dirt, there can be too much of a good thing. Quality fill dirt will contain a high amount of clay, often around 50% at least. If your fill dirt contains over 50% clay, it’s best used to provide a base for cement paths and smaller garden structures, such as smaller sheds and gazebos.
Sand is the other desired component of fill dirt. Fill dirt containing more than 50% of sand is good for using in plant areas, as long as there is a sufficient amount of topsoil placed on top. Fill dirt with high sand content is also the best dirt to use when creating grading and sloping around your home and property.
Fill dirt can also be screened to remove large particles such as rocks and roots, and even help break up larger clay deposits. You can work and screen the fill dirt yourself, or elect to purchase it from a fill dirt provider.
Professional Fill Dirt Delivery
Obtaining quality fill dirt doesn’t have to be a chore. Dirt Connections proudly supplies quality fill dirt to homes and construction sites, and free of charge for 10 or more truckloads. Contact Dirt Connections today by giving us a call or sending us a message online to set up a dirt delivery or your project, or to discuss any of your grading assistance and site preparation needs.