How to Backfill Against a Structure

Complete the structure's foundation as required for sturdiness and to adhere to building codes in your area. Waterproof the foundation by applying a self-adhesive waterproof membrane or applying liquid rubber to the exterior of the foundation prior to backfilling.

Check the building codes in your area. In some states, backfill procedures around structures are specified by the building codes, which you can find on government websites or by visiting the offices of your local government. You must closely follow these building codes in order for your foundation to be legal, which is essential should you ever need to file an insurance claim.

Layer 12 inches of an appropriate structural backfill material, such as crushed stone, against the base of the structure's foundation. Press the stone down with a compactor until the stone is as compact as possible and sits roughly even.

Add another 12 inches of crushed stone against the foundation. Compact the stone down with the compactor. Continue adding and compacting stone against the foundation of the structure until 9 to 12 inches of space remains between the top of the stone and ground level.

Fill the top 9 to 12 inches of the trench against the foundation of the structure with the soil originally removed from the ground, coarse sand or a mixture of the two. Use the compactor to press the soil or sand down into the trench until you cannot compact it any further.

Add more soil or sand to the trench until it sits level with the ground again and compact the soil or sand down as much as possible. Continue this process until the soil or sand sits evenly with the ground's surface. Once the backfill is complete, plant grass seed or lay sod to blend the backfilled trench in with the surrounding lawn.