Any thoughts on a 20' by 20' Pergola

[L C]

Hello,

I know this is for woodworking but I have seen some Pergola posts before and I was looking for suggestions/ideas. I am going to build a new deck and it will be about 20 feet by 20 feet. The deck faces SW so I need to add shade to it. I wanted to build a Pergola over it but I can't figure out how I would do it without putting a post in the middle. Basically how would I span 20 feet? I am in Northern MA so snow load is an issue.

BTW - If anyone knows of a more appropriate group to post this to please let me know.

Thank You

Larry C

[J]

20'x 20' is a pretty big pergola. Usually they are a bit more intimate. Anyway, you would do it pretty much the same way you do a small pergola except use bigger members. They will need to be pretty stout and the connections will require some consideration. This is not something you are going to be able to knock together with some 2x4 and nails. Any competent structural engineer can do the appropriate calculations. In fact I would expect for such a large structure that your local building officials will require structural calculations.

-j

[TWS]

How is 'snow load' a factor on a pergola? A pergola is an open rafter structure whose only 'snow load' would be the weight of snow on the thickness of a rafter. I suspect the rafter load itself is far more significant than any snow that could possibly accumulate on it.

TWS

[mike hide]

But what about the occasional squirrel or the more robust bird here or there.......mjh