A Guide to Home Grading Plan
During construction or a renovation, it's important that when establishing the final grading plan of the home to make sure that water will move down and away from the foundation and exit the lot to an approved storm drain system, otherwise your homeowners could end up with home improvements and repairs down the road they didn't bargain for.
A grading plan refers to the landscaping of the house site and soil elevations. If you don't establish a proper grading plan and the lot isn't graded properly, water from storms and irrigation can run back toward the home and cause moisture issues at the foundation wall, or saturate the soil next to the foundation causing hydrostatic pressure against the wall, which can cause foundation cracks, structural damage and even soil erosion, and leave a home in need of repair.
In other cases, an improper grading plan can mean trouble for the neighbors. Improperly diverted rain and snowmelt runoff can cause erosion and flooding for adjoining lots, leaving the homeowner, and the builder, liable for damages for not following proper building safety standards.
The best practice when working on the finished grade is to follow a grading plan prepared by a civil engineer. A typical grading plan will show the slope of the lot in 5-foot increments, and can provide the site supervisor with the specific information needed for inspecting and managing the grading trade contractor. By closely following the grading plan, the builder can reduce the risk of callbacks and can better control costs associated with hauling or removing fill from the site.
Here are a few other things to think about when getting ready to inspect the final grade:
- One of the most important is to try to do most of the grading during the dry season to prevent erosion of the soil during construction and prevent the need to regrade later.
- If too much of the foundation is showing above grade, or if the final grade is too close to the wall cladding, future moisture issues can occur and can create a path for termites to enter the home. Proper backfill near the foundation is critical.
- All of the soil that is excavated from the site can be reused to help establish final grade. Be sure to cover extra stockpiles of soil or spray the piles with hydraulic mulch to help prevent erosion and excessive runoff.