An Intro to Property Grading: How To Tell You’re Graded Properly

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Have you ever put some thought into property grading? Do you know how your home property is “graded”? You might be inclined to give the land around your foundation an A+, but you can learn it’s actually an F when it starts to rain. If your property isn’t graded properly, the moisture will flow towards your foundation, causing all kinds of problems. Luckily, you can figure out whether or not grading will be a problem in the future, and can even take matters into your own hands!

What Is Property Grading?

Quite simply, the property grading is the level of the ground around your home, and how this ground levels out determines where water will flow. The grading around your foundation should be “positive”, in that it slopes away from your home. This grading is positive because, well, sloping away from your foundation walls is good! You want the water from spring melt, rainstorms, and other sources to be directed away from the walls of your basement. The slope should drop 7 centimetres every 3 metres from the home.

If the grading around your foundation is “negative”, it’s sloping towards the home, and this can lead to water flowing to the walls of your basement. This pressure can exert itself on the basement walls, causing cracking, leaks, and flooding. If there are existing cracks, the water will seep through as it flows and pools causing issues requiring foundation repair. Negative grading needs to be corrected as soon as possible!

Do I Have Positive or Negative Grading for my Foundation?

It’s quite easy to find out whether or not your property is graded properly yourself:

  • Take a string and two stakes; the string should be around 15 meters in length.
  • Put down a stake at the foundation and tie the string around it.
  • Extend the string out fifty feet straight from the foundation, and tie it to your second stake.
  • Lower the end of the string by your foundation to ground level.
  • Measure the distance between the string at the far stake and the ground.
  • Confirm if the distance over 25 centimeters.

You can use this string as a guide when correcting the sloping, should you choose to do it yourself. Another way to see how the grading is If you see pooling around your foundation during a rain, that’s a good sign the soil around your home isn’t sloping away. Mark the places where the puddles are forming, so you know where to correct the issues.

Proper House Grading Diagram from City of St Thomas

If you’re looking to purchase a new home, have a home inspector go through it first. Property grading is part of what they look for, and if there are issues with it, the inspection will highlight it.

Repairing Property Grading

If you’re a hands-on type of person, property grading is something you can do yourself. After figuring out the grade, use a shovel or rent a small loader with a scraper blade to remove the top layer of sod. Remove the topsoil from the low area with the loader; the depth depends on how deep the topsoil is in the yard. Grade the lawn with the scraper blade so it slopes around 7 centimeters every 3 meters away from the foundation. Re-cover the lawn with the topsoil that you removed earlier, working it into the subsoil with a tiller. Smooth it all out with a scraper blade so that the surface is level with surrounding sidewalks, driveways, or walkways. Re-seed or use sod to repair your newly sloped lawn.

As you can see, it can be a lot of work. If you or a home inspector have figured out that you have negative property grading, you can call us to figure out a proper, unobtrusive solution! And don’t forget to call Ashworth Drainage for emergency and preventative foundation repair.