Princeton ZBA approves addition at 105 Mountain Ave with conditions after neighbors raise parking concerns

The Princeton Zoning Board of Adjustment on June 24 approved variances allowing a single‑story addition at 105 Mountain Avenue designed to help the owners house and care for aging relatives.

The board granted C‑ and D‑variance relief for front/side setbacks and an increase in the allowed floor‑area ratio (FAR) after hearing several hours of testimony from the applicants, their architect and engineer, and neighbors. Taylor, the town zoning officer, told the board the site is heavily nonconforming: the lot is undersized and the applicants are seeking a D‑4 FAR variance to increase FAR from the permitted 23% to about 31.36% (existing FAR ≈ 19.3%).

Applicant Ling Gu said the addition — a single‑floor suite with a connecting corridor, family room and bedroom suite — is meant to allow extended stays by elderly relatives and to make their home safer and more accessible. “Granting requested variance will provide much‑needed relief with this undersized lot,” Ling Gu said, arguing that the proposal preserves the house’s character while addressing mobility needs.

Neighbors voiced mixed views during public comment. Kathy Stillo, who lives across the street, said she supported aging‑in‑place options generally but urged the board to require parking to be planned now rather than allow ad‑hoc parking changes later. “Whether it's called an ADU or it's called an addition, it's still…future owners will want to rent it,” Stillo said, pressing the board to require that any new parking or removal of landscaping return to the board for approval.

Board members pressed applicants on accessibility and whether the addition would qualify as an accessory dwelling unit (ADU). The applicants said the addition contains no kitchen and was designed as part of a single‑family residence; the architect noted ramps long enough to meet grade would be infeasible on the narrow lot but proposed lifts as an option. Staff confirmed the proposal, as submitted, does not meet the municipal ADU criteria.

Before voting, board members negotiated conditions intended to protect neighbors and address the site's access uncertainty, including language that would retain board review if the building plan changed. The board approved the application unanimously, adding conditions that the applicants must: record a legally valid access easement for Henderson Avenue before any zoning or building permit is issued; consolidate Lots 19 and 20 into one deed prior to permit issuance; maintain a landscape buffer along their Henderson‑facing frontage; and not expand the defined parking area without returning to the ZBA. The board also placed in its findings a statement that the addition does not meet criteria for an ADU and is not being approved as one.

Taylor and the applicants’ engineer, Catherine Miller, said the site will meet stormwater and impervious coverage requirements and that the engineering review and municipal lot‑grading plan would be required before any permit is issued. The motion to approve — including the conditions above — passed by roll call vote; the clerk recorded all voting members as in favor.

The board carried one unrelated case to July 22 and took a short recess before hearing the next application.

What happens next: The applicants must provide the access easement and lot consolidation documents and satisfy staff review and any municipal engineering requirements before receiving a building or zoning permit.