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.
New Geological Period. In March 2004, geologists added a new time period to Earth's chronologyâthe Ediacaran Period. The Ediacaran Period lasted about 50 million years, from 600 million years ago to about 542 million years ago.It was the last period of the Precambrian's Neoproterozoic Era.Multicelled organisms first appeared during this time. This period is the first new one added in 120 years.he Ediacaran Period lasted about 50 million years, from 600 million years ago to about 542 million years ago. It was the last period of the Precambrian's Neoproterozoic Era. Multicelled organisms first appeared during this time.