Step 14 - Backfilling

With the waterproofing completed, the job today is to install the french drain and backfill. The pipe for the french drain is perforated 4 inch schedule 40 plastic pipe. It is heavy duty and will resist being crushed by the gravel that will be placed on top of it. The corner joints must be glued and taped. Then the entire assembly must be covered by a fabric sleeve that prevents dirt from entering the pipe. The pipe must also be sloped from the back of the garage toward the front so that water will drain out of it and not just sit there in the pipe.

With the pipe in place, a rigid foam board is placed up against the wall to protect the waterproofing from damage by the gravel. Finally, the backfilling can be done. Miguel Gomez did most of the work with his bobcat, picking up the gravel that was stockpiled inside the garage area and carefully dumping it over the wall. It has been a full week since the wall was grouted, so the wall is plenty strong now, but we still want to be careful not to do anything to over-stress it.

Part of the backfilled area is topped with sand so that Mark can get a very smooth and precise finish on the top. Our next concrete pour is going to go on top of the sand.