One of my clients wants me to install a structure over a patio I built last season that will filter the sunlight. I've seen them but don't know what they are called, basically it's a roof with no sheathing, just rafters. At this patio the rafters will run north/south, so they will give a good shading effect. My question is what size lumber is generally used and what would the on center spacing be?
The span will be about 14' and I plan to finish the exposed end with some scroll work.
I call them arbors and pergolas interchangeably, but from what I understand the technical term is pergola if it is attached to the house, arbor if it is not.
Anyway, I like to use purlins to do the majority of the shading, as they're light and if you place enough close together, they can blot out most of the sun.