How To Fix Negative Grading (Step-by-Step Guide)
Does the grade around your house, cause the water drainage to pool up against your house’s foundation? If so, you may have a negative grading issue. We are going to go over exactly how to fix this problem, to save you money from future repairs, that could be very costly.
Negative grading can cause issues with your foundation, that can end up costing a lot of money in damages to the house. To fix negative grading you must add dirt, or remove dirt, to change the grade. You create a slope so that the water drains away from the house.
The landscaping around your home plays a key role in keeping water from damaging your foundation. Foundation repairs are one of the most costly repairs to a home and can be avoided with a proper grade and level to the yard.
We’re going to show you exactly how to fix negative grading so that the water slopes away from your home and the foundation.
What is Grading?
Grading is an important part of having a healthy foundation and yard. Your home’s foundation sits on dirt, and the dirt that is built up around the foundation must be at the correct grade to shed stormwater. This is done to keep water from pooling up at the foundation, and potentially damaging it.
You want to have a downward slope, going from your foundation walls to the rest of the yard. This can be a 6-8 inch slope. The slope should allow water to shed away from the foundation, and into the yard.
When done correctly, your landscaping should be used to help form the slope. This can be done by putting in topsoil, so plants, or grass, can be grown up to the foundation.
Negative vs. Positive Grading
When a yard has a negative grade, this means that the level of the yard goes into the foundation, instead of away from it. This is not good, because water will pool-up on the foundation, and cause problems. To fix negative grading, you have to add dirt to the foundation and change the slope.
Positive grading is when the angle of the slope goes downward from the foundation, draining water away from the house. Your yard should have the proper positive grade to keep water from pooling up. You can change your yard, from negative, to positive grading, by building up soil around the foundation.
How do I Fix a Negative Slope in my House?
To fox a negative slope you have two choices, you either have to build up the soil, or remove soil. The easiest way to do this is to build up soil around your foundation. This is done by adding fill dirt, and topsoil to your foundation’s perimeter.
By doing this, you allow water to shed away from your house. You can also improve the quality of the soil, so that plants can be used as landscaping, around this area. Some people prefer to put a bed of river stones, or gravel, others want plants and shrubbery. Having a positive grade allows plants to grow, while the water sheds away.
How do I Raise the Soil Around my House Foundation?
Raising the soil around your house’s foundation is the easiest way to fix a negative grade. The process involves adding fill soil around the foundation, to build up the level of the soil. Here is a step by step guide, on fixing a negative grade.
Step 1: Remove any debris from the perimeter of your house’s foundation. Use shovels to remove any grass or plants. You will need to prepare the ground for adding the new soil.
Step 2: Add fill dirt or topsoil to raise the level at the foundation. Use fill dirt if you plan on covering the area with gravel. Use topsoil, if you want to improve the soil for planting.
Step 3: Tamp the soil down so that there is a sloped angle. The dirt should move from the foundation, down towards the lawn, in a positive grade.
Step 4: Add more soil, and start to rake the slope, so that there are around 6 inches to 8 inches of a drop in 10 ft. You can use a straight 10 ft 2×4 to help with the grade.
Step 5: Once you have the grade you desire, put the grass back into place, or plant new landscape plants into the topsoil. You can also choose river stones, or gravel, as a perimeter.
Cost to Fix Negative Grading
The cost to fix a negative grade depends on how large your home is. You can save money by doing some of the work yourself, or you can hire it all out to a contractor. The labor is going to be your biggest cost. The job should take 1-2 days.
For a small house, you can expect to pay around $800 in labor and materials. For a bigger house, it will cost around $1200-$1500. This cost can go up, or down, depending on what type of soil you use.
If you use fill dirt and do not care about the quality of the soil, it will be cheaper. It will cost you a few hundred dollars more to use quality topsoil. The higher the quality of the dirt you use, the better chance your plants will have at growing.
The best thing about grading the yard is that you can prep the ground for landscaping and plants. You have a few different options with the landscaping. You can go with river stones, gravel, bushes, or plants.
The grade is going to be where a lot of the water drains, so you want to use plants that do well with a lot of water. If you prepare the soil good enough, the water should drain away, giving your plants just what they need.
Using regular fill dirt is acceptable if you are just going to put gravel, or stone, around the foundation. This can also be great for drainage, helping the water shed away from the house.
What is a Good Slope for Drainage?
You want your slope to be between 6-8 inches. The grade should allow the water to drain completely away from the foundation. You can use a straight board to get the slope just right. Use a 10 ft 2×4, as a gauge, to add soil to your slope.
The 6-8 inch drop, should drop gradually over 10 feet, out from the foundation. Once you have achieved this positive grade, your drainage will always drain away from the house. This will help keep your foundation, and yard, in good condition.
Why is the ground sinking around my house?
A negative grade can cause water to pool up in spots around the yard. You can fix this by filling in the holes with soil and building up the grade, to shed the water. Holes that form around your foundation, can damage the foundation.
Can a sinking foundation be fixed?
A sinking foundation can be fixed, however, this process can be very expensive, and takes a couple of weeks to perform. You can avoid this, by having a positive grade, that keeps water from damaging your foundation in the first place.
I'm a writer that is passionate about home improvements, remodeling, and renovating. I enjoy learning new skills and techniques and sharing them with others.
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