I have a twenty-seven foot long perimeter drain along the side of my house. The front corner is 5/8 of an inch higher than the rear corner. Is this enough to allow for drainage from the front of the house to the rear? Or should I increase the gradient? Is there some kind of formulae that can be used [like a quarter of an inch per linear foot, for example]?
Bob Pellow
Parksville, BC
Bob Pellow
Parksville, BC