$HPMM Fortunately, companies like Hemp Naturals, Inc. (HPMM) are working on the innovative and environmently friendly forms of construction. The lifespan of a building made of concrete, steel, or wood is shorter than that of a flesh-and-blood human. According to the U.S Department of Energy, the average office building lifespan in 2008 was 73 years. The primary cause of this insignificant lifespan span of buildings which are supposed to last for hundreds of years is not far-fetched from the materials used during their construction.