Grade Differential
Lot Grading with substantial grade differences, from the side of the house to the rear of the house, usually occurs on walk-out basements.
Grading approval for these homes may require retaining walls at the rear corners of the house, or on the side lot. These retaining features are usually indicated on the plot plan.
The grading of the drainage swale down the common property line must allow for 10% slope from the foundation walls of adjacent houses, and must provide drainage funtionality for both properties.
Any retaining wall that exceeds 0.6 m in height, or is attached to the house, should attach an engineered design. A permit or design requirements can be obtained from Sustainable Development of the City of Edmonton. Call 311 for details.
The following pictures and diagram are the examples for the requirements to deal with grade differential (for reference only):
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These 2 lots have a large grade differential |
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A retaining wall attached to the walkout basement |
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This walkout basement needs retaining walls |
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This is an engineered retaining wall design example |
