Backfill

The excavation contractor worked on a the back fill last week.  This is the filling in of the space between the outside of the basement walls and the top grade of the lot.  As complete, the waterproofing looks like this.

IMG_7309

At the bottom is the French drain tube.  First they drape a fabric down the wall, along the bottom, and up the side of the grade.  Then they fill it about 60% of the way up with gravel.

IMG_7445

The gravel allows any water that does make it into the ground near the foundation tend ot go down, towards the bottom and the French drain, rather than laterally towards the foundation wall.

Once the have all the gravel in, they wrap it with the fabric like a burrito.

IMG_7469

This keeps dirt out of the gravel.  Dirt would tend to filter down over time and clog the gravel, making it less effective at draining any water down.  Once the gravel is done, they fill the rest up with dirt.

IMG_7472

The initial packing of the dirt and gravel is done with hand-held machines.  The final compaction is done with this grading compactor.

IMG_7654

The finished grading (so far) looks like this:

IMG_7655

They’ve completed about 50% of the back fill so far – just enough to provide access for the concrete contractor to be able to dump sand, and for the steel contractor to drop in the structural steel.  They’ll be back next week to finish the rest.

Leave a Reply

Your email address will not be published. Required fields are marked *