Case Study
San Francisco Home Foundation

The Challenge
The Client had pur­chased a lot in San Francisco for a new home. As is typical of many City lots, there was a zero lot line condition: on one side there was an exist­ing home right at the property line and at 2 others, the edge of the foundation was right at the sidewalk. The plans called for excavating below both the founda­tion of the neighboring house and the City sidewalks.

Action:
The adjacent foundation was sta­bilized by hand-digging alongside and under the adjacent foundation and installing underpinning pits, before the mass excavation phase. Because the soils were type 1 it was not necessary to place shoring in between the shoring pits and it was also possible to make unshored vertical cuts at the sidewalk sides.
The foundation was then installed by placing drainage and water­proofing membranes directly against the cuts and shoring, and shotcreting the foundation walls.

Results:
Because of the techniques used, it was not necessary to over-excavate for double-sided forms and the excava­tion and foundation work were completed without any distress to the surrounding properties.

RWR Construction Inc. 200 Gary Place, San Rafael, CA 94901 (415) 457-5658 www.RWR-inc.com