By Elizabeth Cloutman

Los Altos Hills

The Los Altos Hills City Council is scheduled to vote on the adoption of a revision to the town’s basement ordinance Thursday evening. The revised ordinance, if adopted, would define the kinds of basement construction allowed on residential lots, as well as which types of basements count as floor and development areas. It would not, however, expressly forbid the planning commission from allowing construction of basements, bunkers or cellars not located directly under a home.

The proposed ordinance would require a basement that was built directly under the footprint of a home to be wholly underground on only three sides, or 75 percent of its perimeter length. However, the side not wholly underground could not be located on any part of a lot abutting one side of a road.

No portion of a basement constructed under a home’s footprint, even the exposed side, would be counted against a lot’s allowed development area under the revised ordinance. Residential lots in the semi-rural city are limited to a certain percentage of development, depending upon the slope and size of the lot.

Under the proposed ordinance provision, the planning commission could still permit the construction of basements not under the footprint of the house, including cellars and bunkers.

However, these basements would be required to be wholly underground except for exiting, lighting and ventilation, and they could not encroach setbacks.

Such basements would count against development area, planning commissioners said, since they diminish the amount of area available for planting trees and shrubs.