Archive for May 22nd, 2009

Moving Dirt to Fill the Excavation at the Back of the House

Friday, May 22nd, 2009

It is now time to move 120 yards of dirt to the back of our house and fill and compact the void. 

This has been a struggle.

First, a little background and then a tour of a SIP house being built.  Then, let’s move some dirt.

Background

We changed the shape of our existing swimming pool and moved it closer to our house.  Then, we excavated the basement by 13 ft, which required an OSHA cut at the back.

After the excavation, we shotcreted the bottom of the wall and then formed the back of the retaining wall to grade.  Then, we shotcreted the wall and, when the shotcrete had cured sufficiently, we removed the forms.  This left a dangerous void, some 9 feet deep by 10 feet wide, 54 feet long at the back of our house.  This void must be filled with soil and then compacted to 90%.

Without access from the side of the house (i.e., Winchester Boulevard), we needed to move the dirt across the structure to the back of the house so we could fill the void.  We decided to wait until the hollow core concrete panels were in place prior to moving the dirt. 

Our plan was to use two conveyors, one from Bill Brown Construction Company and the other from United Rentals.  United Rentals delivered their conveyor on Tuesday, May 12 at 2:00 pm.  We thought we would still have a crane on site and be setting the hollow core concrete panels but that was completed and the crane was gone by 12:30 pm).

With the two conveyors in place, we could start moving dirt.

The Challenges of Moving Dirt

Bryan had a difficult time coordinating the movement of the dirt.  The conveyors were a bit finicky and the Bryan doesn’t speak Spanish very well.  He had a tough time explaining that the second conveyor must be going first and then the first conveyor could be started.  Thus, the dirt moved by the first conveyor would be carried by the second conveyor and then dumped.  Otherwise, the dirt from the first conveyor would simply dump onto the second conveyor, overloading it so it couldn’t move.

Similarly, the first conveyor must be shut down first, so the dirt that is being put onto the second conveyor is stopped and the second conveyor is cleared and empty.  Stopping the second conveyor while the first conveyor is moving allows the dirt to pile up on the second conveyor, overloading it.

Observing a House Being Built with SIPs

Before starting the move the dirt, Bryan visited a job site where a house was being built with SIPs.  He wanted to see the construction in person so he could consider the planning and anticipate potential issues on our project.

Site showing slab-on-grade construction with steel moment frames, Hardy panels, and other structural framing.  Note the SIPs stacked under the green tarp.  And the yellow scaffold on wheels.

Site showing slab-on-grade construction with steel moment frames, Hardy panels, and other structural framing. Note the SIPs stacked under the green tarp. And the yellow scaffold on wheels.

The SIPs are built individually and numbered uniquely.  Note the white foam sandwiched between two layers of OSB.  Also, note the 2x splines and blue mastic.  These SIPs are ready to install.

The SIPs are built individually and numbered uniquely. Note the white foam sandwiched between two layers of OSB. Also, note the 2x splines and blue mastic. These SIPs are ready to install.

SIPs in place, showing how they fit together and how window openings are framed in the SIPs.

SIPs in place, showing how they fit together and how window openings are framed in the SIPs.

Building with SIPs results in a very tight building structure.  The airtight nature is the result of all seams being caulked with a mastic, and then screwed together with lengthy screws.

Panel Mastic, from Premier Building Systems (this is the blue mastic that you can see in the other photos).

Panel Mastic, from Premier Building Systems (this is the blue mastic that you can see in the other photos).

SIP screw, used to connect the SIPs between the spines and outer shells (OSB).  Yes, Bryan's foot is for scale.

SIP screw, used to connect the SIPs between the spines and outer shells (OSB). Yes, Bryan's foot is in the photo for scale.

Moving and Compacting Dirt

After getting the conveyors in place, it took a while to get everyone working together and confortable with starting and stopping the conveyors.  We had to ‘fine tune’ the system to minimize the dirt we were losing along the conveyors and from one conveyor to another.

We started moving, and compacting, dirt!

We received our dirt from another site, very close by, with identical soil.  The soild was tested and will yield excellent compaction.

We received our dirt from another site, very close by, with identical soil. The soild was tested and will yield excellent compaction.

Our two conveyors, with the first conveyor taking dirt across the atrim opening and the second conveyor filling the excavation.

Our two conveyors, with the first conveyor taking dirt across the atrim opening and the second conveyor filling the excavation.

The dirt was moved into position with the Bobcat and then shoveled by hand, at the correct pace, onto the first conveyor.

The dirt was moved into position with the Bobcat and then shoveled by hand, at the correct pace, onto the first conveyor.

The second conveyor takes the dirt to the back of the foundation wall, where it is deposited.

The second conveyor takes the dirt to the back of the foundation wall, where it is deposited.

The dirt coming off the second conveyor was distributed by shovel to the correct location.

The dirt coming off the second conveyor was distributed by shovel to the correct location.

Spraying lightly with water and compacting the soil to 90% with a 'jumping jack'.

Spraying lightly with water and compacting the soil to 90% compaction with a 'jumping jack'.

Yes, we’re finally filling the void.

Yippee!