Building codes are a vital part of creating safe, healthful houses, but they can be the bane of many builders' existence. In this article, builder Fernando Pagés Ruiz takes a look at the history of building codes: how they started, how they got to where they are, and where they are going. Building codes began as a way to ensure safely built houses. In the United States, three regional model codes developed, but in 2000, the three regional codes were unified under the International Building Code (IBC). Model codes guide local building authorities. Because adoption of codes is left to municipalities, which can adopt any or all portions of a model code, builders can sometimes be at sea trying to determine which codes apply, depending on where they are working. Codes are revised over a three-year cycle during a lengthy development period. The next set of code changes, which go into effect for the 2015 code update, will reflect a move from prescriptive to performance base, and include water-conservation and indoor-air-quality measures. This article includes commentaries from four experts in the home-building field, a sidebar about how municipalities adopt building codes, and a chart highlighting code evolution over four cycles.