Structural Pergolas are larger pergola structures with long spans between posts. With our Steel Insert System (US Patent #8061106) a four post pergola can be as much as 16' x 16'. There are other options available to save money as well as keep the open area under the pergola. We have several examples of structural pergolas to view. For the 34' x 22' Tan Structural Pergola on steel posts, click here. For the 14' x 16' Pergola on p.t. posts, click here. To view the 10' x 14' Tan Structural Pergola using the Steel Insert System click here.