The Woodside Planning Commission on Nov. 6 unanimously recommended approval of new construction rules that would allow residents with homes in earthquake hazard areas to add on to their residences, a privilege that was previously banned.
The relaxation of a pair of municipal code sections would allow homeowners to add up to 400 square feet of space to houses that are within a 50-foot setback of a known fault, but not on the fault, or within 125 feet of an "inferred" fault, meaning a fault trace that is suspected but not proven to exist, according to the staff report on the proposed change.
The additions to the homes must be on the side not facing the fault and must be accompanied by seismic strengthening work as recommended by the planning department and the town geologist, according to the staff report.
Any addition must be single-story at ground level of the property, according to the report.
Additions to homes proven to be directly on a fault would continue to be banned.
The previous rules limited changes to homes to "maintenance activities only, that would require a building permit," according to the report.
"(Town) staff finds that providing an avenue to making improvements in these existing buildings and structures will result in buildings and structures that are safer than they currently are," the staff report says.
"Buildings and structures that are not on the fault trace are at less risk (but not at no risk) of severe damage ... therefore a modest addition to habitable space would be acceptable."
Any application must be accompanied by a fault investigation report to define the exact location of fault traces on the property.
There are three known faults within the Woodside town limits, including the San Andreas, the Pilarcitos and the Hermit; the latter two are branch faults from the San Andreas, according to Woodside Principal Planner Sage Shaan.
The San Andreas runs directly through the middle of Woodside, the Hermit is at the north end of town and the Pilarcitos runs through the hills near Skyline Boulevard, Shaan said.
All Woodside homeowners within the Alquist-Priolo Special Studies Zone, established by the state in 1972 to improve earthquake safety, were notified in advance of the hearing, he said.
The special studies zone act prohibits new construction of houses within these zones unless a comprehensive geologic investigation shows that the fault does not pose a hazard to the proposed structure.
"These homes all existed before people knew where the fault was," Shaan said.
The Town Council will consider the rules change at a later date.