malformalady: A sod or turf roof is a traditional Scandinavian type of green roof covered with sod o
malformalady: A sod or turf roof is a traditional Scandinavian type of green roof covered with sod on top of several layers of birch bark overlaying wooden roof boards. Dating back to before the Viking and Middle Ages, it was the most common type of roof on rural log houses and cabins in Scandinavia until the late 19th century. More on my Blogspot -- source link