Complex sentence: In 1966, the members voted against building there, as older members were attached to the existing building, and concerned about expenses, but by the early 1970s, the situation could no longer be ignored.
Split into simpler sentences: In 1966, the members voted against building there, as older members were attached to the existing building, and concerned about expenses. By the early 1970s, however, the situation could no longer be ignored.