A support system for a sign mountable on at least two spaced apart foundation members, the system comprising: i) a base, preferably a length adjustable base, having a first end and a second end; ii) a vertical sign support having a first end and a second end wherein the second end is connected to the base; iii) a first foundation member bracket for connection to a first foundation member, the first foundation member bracket proximate the first end of the base; and iv) a second foundation member bracket for connection to a second foundation member distant the first foundation member, the second foundation member bracket proximate the second end of the base.