Though a proposed new mixed-use building on Park Street meets New Canaan’s development guidelines generally in terms of planning for housing and streetscapes, it could dramatically alter an important vista downtown if it’s located too close to the road, officials say. Replacing the small 1.5-story house at 121 Park St. with a two-story retail-and-residential structure that sits just five feet off of the sidewalk may not work “if you look at any context of the elevation looking down that street,” according to Planning & Zoning Commissioner Dan Radman, an architect. “All of us drive down that street multiple times a day—you are going to have a 2.5-story structure right at the corner of that transformer, looming over Park Street,” Radman said during the group’s regular monthly meeting, held March 29 at Town Hall. “That creates a condition going southbound on Park Street which has a very will create a very large impression on the street, in particular because you have a got a new structure existing past [Mrs. Green’s] by about eight or 10 feet.