Correct Grading

Correct grading to direct water to least 2m away from foundation.

A man shovels dirt

The slope of your property relative to your home is a critical factor in your home's flooding risk. Water will always flow downhill. If your home is at or below grade, it is always at a greater risk of flooding. Checking and correcting your property's grade (slope) helps direct water towards stormwater major collection systems or natural systems. 

What is correct grading? 

  • Driveways: 1-2% minimum slope away from your home. 

  • Windows and doors  

  • Window wells: Windows less than 10-15cm (4-6”) above the ground should have a window well installed 10-15cm (4-6”) above grade. Installing window well covers reduces your risk even further. 

  • Doors and stairwells: Doors less than 10-15cm (4-6”) above the ground should have an accompanying drain installed. This drain should not be connected to the sanitary sewer system. A stairwell sill 10-15cm (4-6”) above grade reduces your risk even further. 

  • Make sure to examine and repair or install seals around your windows and doors to keep water out in case of floods. 

  • Foundations  

  • Minimum 5% slope away from your home within 1.8m (6') of your home. The ground within 1.8m (6') should not easily soak up water. Instead, there should be light water pooling.