Police responded to a report of a house collapse at 125 Crown Terrace around 10:30 p.m.
The home is owned by Melvin Murphy, a San Francisco port commissioner who also served on the city's Building Inspection Commission from 2006 until 2012.
The 100 block of Graystone Terrace is closed to traffic with no estimated time of reopening, police said.
Inspectors from the city's Department of Building Inspection were on scene this morning assessing the site to investigate the cause of the collapse, department spokesman Wiliam Strawn said.
The property owner's engineer will have to develop a mitigation safety plan and bring it to the city to help correct the situation, Strawn said.
Crews were in the process of placing a new foundation at the home before the collapse, he said.
A permit issued by the department last month approved vertical and horizontal additions to the home as part of the remodeling project.
A neighbor who did not want to be identified said the building, which overlooks Graystone Terrace, appears to be a total loss.
She said the property is a small home built in the early 1940s.
Resident Douglass Garibaldi said the house fell about 50 feet down a hill.
"The rest of it could fall at any moment," he said.
