Backfilling is all too often the beginning of basement destruction. But the problems associated with improper backfilling can be avoided by taking a few simple precautions.The four key elements to backfilling are:
- Protecting the wall during backfilling: Backfill only after the basement floor slab and the first-floor deck are in place. For those who don't want to wait, brace the walls before the deck is built. Vertical steel bracing is recommended.
- Choosing the right backfill material: The object should be to restore equilibrium, as nearly as possible, to the soil moisture system. That usually means putting back in the same soil that came out, unless it is a poor soil.
- Compacting the backfill: Compaction is needed to reduce the amount of soil settlement that occurs with time. To avoid damaging the walls, place the backfill in 6-inch-thick lifts and have the laborers tamp it with foot pressure or hand rammers.
- Final finishing to the correct grade: Diverting surface water away from the foundation is one of the most effective ways to prevent basement leakage. The minimum slope for finished grade should be one-half inch per foot for at least 10 feet away from the foundation.