Pergolas made of metal are quite popular and the choices are iron, steel or aluminum. Iron and steel have the risk of forming rust which will make them not look good in years to come. No doubt, iron and steel are strong, durable and long lasting, but if rust is formed it will spoil the beauty and will require deep scrubbing and repainting every two or three years. Aluminum is lightweight and does not rust. Despite it’s lightweight, it is still quite strong too and there are powder coat materials which can be utilized to give a special painted metal look to the pergola. It is easier to wash pergolas made of aluminum as well.