In "Word Focus" Glenn McClure writes:
One of the keys to understanding our printed text is the word edify, which occurs both in Romans 14:19 and in 15:2, where it is translated “edification.” This is a key word because it describes one of the basic motivations of Christian action. But it is also a word that is not used in casual conversation. The Greek word is actually a combination of two words, one meaning “to build” and the other meaning “a house.” So the obvious meaning is “to build a house.” Clearly the intended meaning of this word can best be visualized by remembering the last time you observed a construction project. Each piece of material was carefully put in place so that, when the project was completed, the building would be able to bear the load expected of it. That picture suggests that when Paul exhorted us to “edify [one] another” he imagined that every Christian is a part of the construction crew that is erecting a fellow Christian. The goal of our work is that our efforts will enable our fellow Christian to bear the load he or she will be expected to bear. What should inspire in us a sense of awe is that we as Christians are being asked to do what God himself was said to be doing in Jeremiah 24:6.
Source: Building Christian Relationships: Adult Teacher's Insights, page 46.