The first time I visited Norway I saw these remarkable houses covered by grass roofs. I was fascinated by the look of them. A long time before, I had met a Norwegian young man in one of the workcamps, where we worked during the holidays as volunteers. He told me a lot about Norway and also about the grass roofs. He said that some farmers put their goats on top of the roofs to keep the grass short and to prevent trees from growing on the houses.
Maihaugen in Lillehammer
"A sod roof or turf roof is a traditional Scandinavian type of green roof covered with sod on top of several layers of birch bark on gently sloping wooden roof boards. Until the late 19th century, it was the most common roof on rural log houses in large parts of Scandinavia.
The load of approximately 250 kg per m² of a sod roof is an advantage because it helps to compress the logs and makes the walls more draught-proof. In winter the total load may well increase to 400 or 500 kg per m² because of snow.
The birch bark underneath ensures that the roof will be waterproof.
The term ‘sod roof’ is somewhat misleading, as the active, water-tight element of the roof is birch bark. The main purpose of the sod is to hold the birch bark in place. "( Wikipedia)
.A sod roof has a lot of advantages: Firstly it is cheap, for the materials used for it, like birch bark and grass turf, are available in abundance.
Secondly: It's an ideal way of insulation in the cold and long Scandinavian winters.
But it requires a lot of time! No problem, for neighbours and friends are invited to join in a roofing party
This practice of covering roofs with birch bark and grass sods in Scandinavia, dates back to prehistory. The Vikings and People from the Middle Ages built their houses this way.This lasted until the beginning of the 18th century. Gradually houses in towns were built with tiled roofs and sod roofs almost disappeared, This was considered to be a threat to ancient traditions. This caused a general revival of vernacular traditions, including these sod roofs.
Mountain lodges and holiday homes with sod roofs became very popular. Open air museums like Maihaugen in Lillehammer, and reservations all over Norway, contributed to a better knowledge of the ancient culture of Norway and the rest of Scandinavia.
Røros, old mining town