A gazebo is an attractive outdoor structure that also serves a very practical purpose. It’s a pleasant place to sit in the fresh air (and perhaps enjoy a meal with friends and family), which is topped by either a semi-open roof that provides shade or a waterproof shingled roof that protects you from the elements. The gazebo’s structure can comprise just posts and no walls, or low walls about three or four feet high. While a gazebo without walls requires less lumber, installing walls will enable you to attach benches and add screens if you want to keep out pesky bugs.