Photos

Why Do Scandinavians Grow Grass on Their Roofs? (PHOTOS)

They look like hobbit homes or houses for fairies, but Scandinavian grass roofs are the real deal. Some are green as pasture, while others are golden in color. Some grow wildflowers, some grow trees and some have even invited the occasional goat to graze on top.

(MORE: Incredible Gardens Growing in Unexpected Places)

Scandinavians have been growing sod roofs for hundreds of years, and reports claim that the tradition dates back to prehistoric times. While the aesthetic value is obvious, there are practical reasons for the grass roofs as well.

The sod roofs support biodiversity by recreating a place for local plants to grow, even within urban areas. The roofs offer places for birds to nest and insects to breed. The vegetation on these roofs also helps to soak up rainwater, and may even reduce annual runoff by 40 to 90 percent, depending on roof design, plant varieties and roof pitch, according to the Scandinavian Green Roof Institute.

Perhaps the reason grass roofs were originally used hundreds of years ago is the plants' role in insulating the home. The plants can keep warmth within the home in the winter, as well as keep the house cool during summer months. In modern times, this could reduce electric and gas bills, and even reduce carbon footprints. The vegetation also acts as a barrier to absorb the noise of the outside world, keeping life indoors quiet and peaceful.

(MORE: 15 Cities That Have Committed to Clean Energy)

The roofs are traditionally built with water-tight birch bark, and topped with soil and sod, which helps to hold the birch bark together. Modern green roofs might use water protective membranes and anti-root membranes made from synthetic materials.

MORE FROM WEATHER.COM: Gardens in Unique Places