Patio on Sloping yard | Walkout Basement | Landscape Retaining Walls

by Kevin
(Ontario Canada)

Here's a question about creating a patio on a sloping yard with a walkout basement.

I have a walk out basement to our backyard. The yard slopes off about 7 inches every 8 feet. I want to have a terraced patio using standard 20" by 20" patio stones. What should I use for a retaining wall, and how would I do it? Not sure were to start?

ANSWER
Hi Kevin,
As far materials go, you can use decorative concrete block or natural stone. The block will be less expensive and they have some very nice ones available, probably even on to match whatever paver you are using for the main patio design. See my page Landscape Retaining Walls.

For starters, decide how large you want your patio to be, extending out towards the slope. Then determine how high much higher the land is there than your patio level/grade. I am not sure if the land is sloping down and away from your house or up and away. In either case, the above still applies. If it slopes up, you will be cutting the land and if it slopes down you will be filling the land.

Once you know the difference in elevations you will know how high the landscape retaining walls must be. If the slope is 7 inches in 8 feet, that's not too bad when building a patio on a sloping yard. It's about a 7% slope which is even less than a handicap ramp. From the point it starts sloping, if you went out 10 feet, the wall would be less than a foot high. If you went out 15 feet, the wall would be just a tad over a foot high.

You could raise the wall a bit if you like to 18 inches high and then have a nice seatwall along the patio outside your walkout basement.

Wherever the wall is, the ends have to meet the existing grade at some point.This can be done by stepping the wall up or down (depending on how your slope goes) or ending it with nice large boulders.

Most companies that sell the decorative block will provide drawings showing the proper method of installation, including excavating, base, etc.

If you have further question let me know. You can also contact me by email.