Houses in the Reyn district of Tórshavn have grass roofs for survival and tradition. Early settlers used these roofs because wood and stone were hard to find. Here are the advantages - Insulation: Grass and dirt keep the inside warm in the winter and cool in the summer. Weather Defense: The heavy sod absorbs fierce ocean winds and muffles heavy rain. No Trees: The islands have no native trees to make wood shingles. Grass is an easy, free material. Eco-Friendly: The grass absorbs climate-warming carbon dioxide and creates homes for birds and bugs. Maintenance: The grass must be mowed like a normal lawn, usually once or twice a summer!