Site grading is an important step in the land development process, and it’s also one of the least understood. The purpose is to create a smooth, even plot with only slight variations in elevation, to ensure the land is ready to support whatever’s developed on it. From clearing the land of vegetation and unwanted debris to adding the final layer of topsoil to jumpstart the growth of landscape, grading is a crucial part of site preparation.
There are often several steps in the site grading process; however, they generally fall into two categories: rough grading and finish grading. Here’s a closer look at why proper grading is important, and an in-depth look at the key parts of the process.
A quick overview on the importance of site grading
Site grading is an important step in every development project—not only because it provides a smooth, level base for laying a good foundation, but because it determines how well water drains from the property. Poor, insufficient grading could create big problems in the short- and long-term, causing extensive damage to properties when water accumulates near foundations.
Developers use several techniques to ensure proper drainage, like sloping the land away from the property, building retention ponds or diffusing water to prevent erosion. Good site grading reinforces key elements in the existing landscape, while restricting water runoff. Strategic grading can even improve soil quality!
In short, reliable and precise site grading is critical for any construction project, from small-scale residential projects to large-scale mixed-use developments. It ensures you have a solid base to build on, along with efficient water drainage that prevents damage to both buildings and topography.
Rough grading: slope and shape
Rough grading focuses on creating an ideal shape and slope for land under development. The process often includes flattening the land, and it should always be performed by a professional who not only understands slope, but also has a comprehensive understanding of drainage. Slope the land too much toward a building and you could be dealing with flooding. Slope the land too far away, and you could end up facing erosion issues. For any type of development, neither is good.
During the rough grading process, graders remove dirt from high areas and place it in lower areas to create a smooth surface. They also install any drainage components—like v-ditches, down drains, benched terrace trains, and more—that take stormwater run-off from your site. While every project is different, rough grading can be a long process, simply due to the volume of dirt moved.
In some cases, rough grading can also include site clearing and demolition, depending on how long the raw land has been sitting for. Graders—or subcontractors—will come through and remove vegetation and other debris from the site, so nothing gets in the way of the grader as they’re moving dirt.
Finish grading: contour and elevation
Finish grading can only take place once the rough grading process is complete. This step in the development process involves adding or removing soil to within 1-2 inches of the existing grade. At the end of the finish grading process, you’ll have the final contour and elevation of the ground you need to start building on.
During this development step, graders may remove large chunks of soil, rocks and other unwanted debris. The result is a smooth surface that’s ready for planting, seeding or sodding, as well as building.
Often, graders will finish the surface with materials that promote the growth of landscaping. For many construction projects, this includes adding a coating of screened topsoil or similar materials to complete the project and prepare it for building. True to its name, finish grading is all about finishing this key step in land preparation.
Grading paves the way for development
Site grading is an important step in any development, whether you’re building a single-family home or a large-scale commercial development. Proper site grading always starts with a comprehensive grading plan that not only optimizes efficient use of existing materials, but also helps developers save money during the actual grading process—when professional graders and their machines are moving earth. Need help determining if your plans and specifications include an appropriate site grading strategy? The team at Sandbox Development Consultants performs intensive due diligence that helps developers understand the ins and outs of site grading. We strive to add value, mitigate risk and maximize efficiency during this critical step of the development process. Reach out to our team today to learn more.