I searched for the answer to this question on the forum but didn't find what I was looking for so here goes. I am getting ready to construct a pergola roughly according to these plans:
http://www.popularmechanics.com/home/how-to-plans/pergola/3352816
They suggest a western red cedar structure with the exception of the posts which are to be pressure-treated pine 4x4s wrapped with cedar 1x4s. Their design has the posts sitting in anchors slightly above grade. In my case the posts will be sitting slightly below the grade of my patio which has pavers i.e. concrete footings were poured with CBSQ anchors so that the lower edge of the posts will be around 1.0 inch below the top edge of the pavers which themselves rest on stone dust and should drain quickly. So in terms of moisture it's not as ideal as having the posts sitting above grade but probably better than having the posts embedded several feet down in the footers.
Anyway, my question is whether it is better in terms of longevity of the structure to use pressure-treated pine 4x4s or use cedar 4x4s. I've read differing opinions about which lasts longer. Generally pt-pine is supposed to be prone to movement as it ages so this would be a disadvantage though some say it lasts longer. Thanks.
http://www.popularmechanics.com/home/how-to-plans/pergola/3352816
They suggest a western red cedar structure with the exception of the posts which are to be pressure-treated pine 4x4s wrapped with cedar 1x4s. Their design has the posts sitting in anchors slightly above grade. In my case the posts will be sitting slightly below the grade of my patio which has pavers i.e. concrete footings were poured with CBSQ anchors so that the lower edge of the posts will be around 1.0 inch below the top edge of the pavers which themselves rest on stone dust and should drain quickly. So in terms of moisture it's not as ideal as having the posts sitting above grade but probably better than having the posts embedded several feet down in the footers.
Anyway, my question is whether it is better in terms of longevity of the structure to use pressure-treated pine 4x4s or use cedar 4x4s. I've read differing opinions about which lasts longer. Generally pt-pine is supposed to be prone to movement as it ages so this would be a disadvantage though some say it lasts longer. Thanks.