Ithaca council committee hears ADU outreach, leans against owner-occupancy requirement

Planning Department staff briefed the Ithaca Common Council’s Committee of the Whole on February 12 on a months-long public outreach effort and draft technical standards for an accessory dwelling unit (ADU) ordinance.

The presentation summarized an open-house and an online survey of about 290 respondents, most of whom were homeowners, and outlined proposed local rules on where ADUs would be allowed, maximum size and height, setbacks, and how ADUs would be treated when they are part of existing structures versus new construction. Planning staff said survey respondents were generally supportive of allowing ADUs but split on whether properties with ADUs should be owner occupied. Staff recommended no parking requirements for ADUs, a 5-foot side setback for new detached ADUs (changed from a 4-foot draft), a 20-foot maximum height and two-story cap for new ADU construction, a 40% size limit for attached ADUs, and a 600-square-foot maximum footprint for detached ADUs. For conversions of existing structures, staff proposed no new setback requirement but continued adherence to building and fire codes.

Why it matters: Council members framed ADUs as one piece of a broader housing strategy. They raised concerns about impacts on neighborhood character, student housing pressure in areas such as Belle Sherman and South Hill, financing and resale complications tied to owner-occupancy limits, and whether ADUs would meaningfully increase affordable supply given construction costs.

Council discussion and informal guidance: Council did not vote on an ordinance but used public straw polls and discussion to give staff direction. After debate, a majority of council members indicated they did not want an owner-occupancy requirement written into the draft ordinance; staff was asked to draft the ordinance without that requirement so it can be amended later if needed. Council also indicated unanimous support for allowing short-term rentals (STRs) in ADUs only when the property is owner occupied, consistent with the city’s existing STR framework. Finally, staff reported an overall sense that the council would opt into two New York State ADU tax-exemption programs when drafting the ordinance.

Technical, outreach and program details: Staff said the outreach included an open house at the Tompkins County Public Library (about 25 attendees, mostly from the Third Ward), an informational web page, and a three-week survey. Staff cautioned that 90% of survey respondents were homeowners while homeowners make up fewer than 30% of city residents, and that survey responses therefore do not represent the citywide population. Staff also reported that Tompkins County has opted into the state ADU tax exemptions and that the county assessor has discussed how exemptions would apply (an exemption applies to the increased assessed value from adding an ADU and would taper over several years under the programs discussed).

Next steps and constraints: Staff said the survey and outreach material and a September 2024 memo are posted to the planning web page and asked the council to provide the discussed direction so staff could draft an ordinance. Council directed staff to draft the ordinance consistent with the straw poll results and to return with a proposed regulatory draft for further committee review and amendment before any formal vote.

Ending: Planning staff thanked the committee and said they will return with draft ordinance language and additional analysis, including further work on financing and accessibility concerns raised by council members.