City Planning Board chairman Justin Hartzog said yesterday that parking problems in the Cambridge area may be partially solved if a new off-street parking ordinance now before the City Council is approved.

The main point of the new ordinance is a change in zoning laws to permit construction of parking lots holding from eight to 30 cars in residential areas. Speaking at yesterday's Council meeting, Hartzog said the new lots would provide vitally needed off-street parking, clearing the main streets for traffic and short-time parking.

He pointed out that the number of cars in Cambridge has increased by 50 percent since 1945. Because there are not sufficient funds available to widen streets, off-street parking is held as the only realistic solution.

Citizens had a chance to voice objections to the new measure in a City Hall hearing yesterday. Objections to the proposal, as now worded, center around the fact that to build a lot, one must only secure the permission of the three-man City Board of Appeals, and not that of abutting neighbors. Other details of the plan were generally approved.

Off-street parking has been debated for several years at City Hall, but with no success. It came up for consideration as long ago as 1949, in a report prepared in part by University officials.