1. Brace the Concrete Wall Backfilling a freshly built concrete wall can cause it to bulge or crack, requiring a costly fix. If the floor deck isn’t installed, brace the basement walls first using heavy timbers at about two-thirds of the wall height, and about 12 feet apart (for an 8-foot wall).
2. Use Coarse Granular Material Cover the footing drains with gravel and filter fabric. If the existing site soils contain clay or organic matter, bring in better fill to complete the backfilling. “Pit run” or “bank run” gravel makes an economical and effective fill.
3. Compact the Backfill Compacting the backfill as you place it will prevent the surface from settling over time—you don’t want to end up with a slope that drains toward the house. Best practice is to place your material in 6-inch to 12-inch lifts, and to compact it by hand using a “jumping jack” compactor.
4. Slope the Final Grade Set the finish grade so that there’s a good positive slope away from the foundation for drainage. About 6 inches of slope in 10 feet is a good rule of thumb, but making the slope a bit steeper to allow for possible settling won’t hurt.
