Question about building a Pergola
I have a question about building a pergola. Our deck is on the 2nd floor of our house (with no stairs coming down) and are looking to build a pergola on it. What will be the best way to attach the 4 vertical posts to the deck if we are placing it in the center of the deck?
Replies
pergola on dexk
Wow. That's like asking, how high is up.
What size is the deck? How is the deck built? (column sizes, beam sizes, joist sizes, decking sizes, decking material, connection to house, etc etc.)
What is the proposed pergola size, design? (is it free standing, attached to the house, etc.)
Have you talked to a bulder, architect, engineer? Photos would be nice.
Think in other categories.
Clients recently wanted me to replace a patio cover on the side of their house. The eave height was low, so getting any pitch from the fascia would have been difficult. (The cover we tore off was low.) We decided to raise the cover and let one side drain onto the roof. This would give us the height we wanted. I didn't want to get into too many structural issues, but I wanted something distinctive. Just about the time we decided to use multiple pergolas, these units came on sale at Costco. The clients agreed so we put 4 of them together with scuppers between them. We shortened the legs to sit on the roof and lengthened the legs on the patio. They bolt down. The size of each was 10 x 13. Although this was on a patio slab it would work equally well on a deck. We got exactly the look we wanted at a reasonable cost.
The hard thing will be keeping the pergola from falling down. Since the posts will (presumably) end at the deck surface there's nothing to prevent them from leaning one way or the other, so your design must include substantial knee braces overhead.
Beyond that you need to prevent the pergola from being blown away in the wind, meaning the legs must somehow be tied down (with something more substantial than a few nails).
pergola on dexk
You could let the columns penatrate the decking and tie into the joist and anchor them similar to railing post. Also, depending on what is below the deck, you could let the columns extend a couple of feet below the joist and diagonal brace them back up to the underside of the deck/joist.
You really need to know more about the original deck. Like can it support the additional forces that will be created by the addition of a pergola type structure.
All, thank you for your responses on this. It was greatly appreciated.