A crowd of Eichler-loving residents overflowed the Mitchell Park Library conference room in Palo Alto Tuesday night to offer the city their ideas for guidelines to preserve their neighborhoods' character. But despite their united interest in the thorny subject, they also stressed that one size does not fit all.

City officials held the workshop to explore creating design guidelines for neighborhoods developed mostly in the 1950s and 1960s by Joseph Eichler, whose architects favored a clean, Midcentury Modern aesthetic of open floor plans, post-and-beam construction and floor-to-ceiling windows.

In Palo Alto, there are more than 30 Eichler developments, according to Jonathan Rush, the city's consultant from the historic architecture firm Page & Turnbull. He called the concentration "really astounding."

The City Council approved hiring consultants to create potential guidelines after a number of neighborhoods petitioned for single-story overlay zoning, which would prevent the addition of second floors to homes. Given Eichler homes' large windows, residents of one-story homes have expressed concerns that people living in adjacent two-story homes could invade their privacy.

The council approved two single-story-overlay zones in 2015 (Los Arboles and Greer Park North) and rejected two applications in 2016 for Royal Manor and Faircourt #3 and #4 -- the latter in part based on the lack of homeowners' support and the confusing process that accompanied the bids.

Home owners have also, over the years, fought over the design of houses added to their architecturally distinct neighborhoods.

In light of the ongoing challenges, the council directed staff in last May to evaluate developing design guidelines and to explore whether the city should also review and amend its codes and regulations regarding Eichler neighborhoods.

Rather than favoring hard-and-fast rules, residents Tuesday had several different suggestions for how people could expand their homes.

One option would be to allow construction of a basement, some residents said. Others suggested a second story could be made less potentially invasive if homeowners add windows to the front of the building rather than the back.

Still others recommended that remodels could add space to the front of the house -- pushing out into the front yard by 6 feet or converting the garage, if the city were to ease requirements on the use of garages for vehicles. Residents said it's no secret that most people park in their driveway or on the street rather than using their garages, so the space might be used as an addition.

Some meeting attendees favored allowing second stories, but only if they are small and discreet.

But whatever regulations are in place, the participants urged some flexibility. One resident noted that the roof lines of some original Eichlers are "ugly forms" and said homeowners should be allowed to swap shapes with a better-looking Eichler roof design.

As for the method that the city takes to govern the process, participants were not cohesive in their opinions about whether the council should revise its codes and regulations.

Code changes could improve the process by which neighborhoods apply for single-story overlay zones. City codes could also establish a specific "Eichler Overlay" combining district that would allow for compatible second-story additions and create criteria for compatibility, according to a staff report.

The city might also modify its Individual Review guidelines to require review of house projects with specific guidelines for second-floor additions and new two-story homes in Eichler neighborhoods. The Individual Review would consider privacy and compatibility with nearby homes.

The city could also add a review process for one-story homes in Eichler tracts.

Some participants on Tuesday favored guidelines but not codified regulations.

"Regulations should not be so stringent to make it difficult to buy and repair the home," one resident wrote on a Post-it, which was affixed to a wall poster as part of an exercise at the meeting.

Others stressed that whatever policy is adopted, it needs to have "teeth" lest it be unenforceable.

In addition to discussing the potential guidelines, the crowd Tuesday chastised city officials for not giving adequate notice of the meeting and for holding it during Passover, when many people could not attend.

Citing Eichler neighborhoods' past and fractious bids for single-story overlays and other restrictions, residents asked that city planners and consultants make a more concerted effort to involve the neighborhoods in this process.

Consultants and the city plan to work on the guidelines and potential code changes and share a draft with the public in August. They will hold a second community workshop on the draft in September, to be followed by an information hearing before the Historic Resources Board that month.

A hearing with comments and adopted recommendations by the Planning and Transportation Commission is scheduled for October. The council would then hear and consider the design guidelines and zoning changes in December with final adopted guidelines to be published in January.