LOWER MERION -- Over the last several years, construction of most of the new mixed-use buildings in Lower Merion has taken place in Bala Cynwyd and, to a lesser degree, Ardmore. But now some of that development is moving westward with recent projects in Haverford and Bryn Mawr. In February, the Lower Merion Board of Commissioners approved the tentative sketch plan for a new four-story mixed-use building at 355 West Lancaster Avenue in Haverford. Those plans included the demolition of five office buildings and constructing a new 58,597 square foot footprint mixed-use building. - Advertisement - The new building will have 121 residential units with 4,000 square feet of first-floor retail space.