Metal roofs, as evidenced by their 50-year lifespan, outlive asphalt shingles by more than three times their lifetime. While asphalt shingles are easier to install than metal roofing, they require regular maintenance and will need to be replaced in 15 to 30 years, which means an added cost to homeowners.
The term Modern era, Modern period, or Modern Times is used by historians to loosely describe the period of time immediately following what is known as the early modern period. It is to be distinguished from the term of Modernity. 1. The early modern period lasted from the end of the 15th century to the middle of the 18th century, circa 1450 (moveable type printing press etc) and 1492 (start of European Colonialism) to 1750 (the Enlightenment) and the beginning of the Industrial Revolution. 2.
The Paleolithic Era (or Old Stone Age) is a period of prehistory from about 2.6 million years ago to around 10000 years ago. The Neolithic Era (or New Stone Age) began around 10,000 BC and ended between 4500 and 2000 BC in various parts of the world. In the Paleolithic era, there were more than one human species but only one survived until the Neolithic era. Paleolithic humans lived a nomadic lifestyle in small groups. They used primitive stone tools and their survival depended heavily on their environment and climate. Neolithic humans discovered agriculture and animal husbandry, which allowed them to settle down in one area.