Dear Members of the Tiburon Design Review Board,

We, the undersigned residents and neighbors of the Belveron neighborhood, respectfully submit this petition to express our opposition to the proposed design for the residence at 68 Mercury Avenue (Design Review File No. DR2025-093).

Our concerns are based on a careful review of the submitted plans and the Town of Tiburon’s Second-Story Residential Guidance, which was specifically developed to protect neighborhood character, privacy, views, and overall livability in areas such as Belveron.

1. Incompatibility with the Established One-Story Neighborhood Character
The Belveron neighborhood is predominantly composed of one-story homes, a pattern explicitly recognized in the Town’s Second-Story Residential Guidance. The proposed second-story addition at 68 Mercury Avenue represents a significant departure from this established character. Rather than remaining subordinate or minimally visible, the new upper level introduces additional height, bulk, and visual presence that is inconsistent with the surrounding homes and the intent of the guidance to preserve neighborhood scale.

2. Adverse Impacts on Views and Neighborhood Aesthetics
The proposed second-story massing has the potential to block or materially alter existing views enjoyed by neighboring properties. The Town’s guidance identifies the protection of views as a critical consideration when evaluating second-story additions. In this case, the design does not adequately minimize visual obstruction or blend with the existing streetscape, resulting in a structure that appears visually dominant rather than context-sensitive.

3. Privacy Impacts from Upper-Story Windows and Elevated Living Areas
The addition of upper-level windows and living spaces creates direct privacy concerns for adjacent properties. Elevated sightlines into neighboring yards and homes undermine the privacy that residents reasonably expect in a single-story neighborhood. The Second-Story Residential Guidance specifically cautions against privacy intrusions of this nature, yet the current design does not sufficiently mitigate these impacts.

4. Increased Bulk, Massing, and Potential Shading Effects
The overall scale and massing of the proposed second story may result in increased shading and a sense of enclosure for nearby homes. The guidance calls for careful attention to bulk, mass, and sun/shade impacts, particularly in neighborhoods not historically designed for two-story development. The proposed design does not appear to adequately step back, reduce volume, or otherwise soften these impacts.

Request to the Design Review Board
For the reasons stated above, we respectfully request that the Design Review Board:

Deny approval of the project as currently designed;
Require a redesign that eliminates the second-story addition, consistent with Belveron neighborhood patterns;
Ensure any revised proposal fully addresses privacy, views, bulk, and shading impacts in accordance with the Town’s Second-Story Residential Guidance; and
Give substantial weight to neighborhood compatibility and community input in its final decision.

We appreciate the Board’s careful consideration of this matter and its continued commitment to preserving the character and livability of Tiburon’s residential neighborhoods.