# Triangular Pergola: Anchoring Beams to Corner Post



## SaintDonan (May 10, 2013)

I have dug around on the net and on this forum and have not seen much in the way of how to sandwich beams around the back corner post of a triangle shaped pergola. A square or rectangle pergola is easy since none of the posts have beams connecting from two different angles while in the same plane, so sandwiching the post with 2x10's is simple enough (or whatever size you are using). Is there a standard recommendation on how to handle post attachment for the lumber that runs on the inner side of the post (the outside pieces obviously need no special treatment)? I suppose it may just be how to handle that fourth piece as the two outside pieces and one of the I side pieces can be bolted without causing any issues with beams intersecting each other. 

Thanks!
Steven

P.S. I realize that the answer may be to set them on top of the posts instead of going with the common sandwich design, but I am hoping to not have to change the look, not to mention the additional expense.


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## Seattle2k (Mar 26, 2012)

It's hard to follow what you're asking. Although, I think I understand what you're saying, please post a photo or draw us a picture.


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## SaintDonan (May 10, 2013)

Seattle2k said:


> It's hard to follow what you're asking. Although, I think I understand what you're saying, please post a photo or draw us a picture.



Will do. I was trying to take advantage of the time I am spending sitting in the airport. :-/ I will be back home tonight and can post something (hopefully tomorrow).


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## GBrackins (Apr 26, 2012)

Welcome to the Forum!

I have to ask, why a triangular pergola? not saying I'm against that, just trying to understand the why .... have a safe flight


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## kwikfishron (Mar 11, 2010)

I've done one before with the sandwiched supports to the post. I ripped the 6x6 post to the angle of the intersections from about a foot above the post base. I thought it would look weird but in the end it was pretty cool. 

My first choice is always to have the beam sitting on top of the post. That takes a custom post to beam saddle to make that look right.


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## SaintDonan (May 10, 2013)

I sketched these on the plane. Considering I am horrible with sketching ANYTHING, I think they at least get the idea across. This is what I thought up while flying, and is based on using 2x12 lumber. I also planned on putting a decorative wrap around the post which would help serve to support it instead of all the wieght being on the 2x6x8 section that actually overlaps the post. Since the other posts will be 6x6, I think this could/should work and the spacing will be correct. 




I saw a few pics online, but cannot really tell how they were done in the back corner.


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## SaintDonan (May 10, 2013)

GBrackins said:


> Welcome to the Forum!
> 
> I have to ask, why a triangular pergola? not saying I'm against that, just trying to understand the why .... have a safe flight


Thanks for the well wishes. I made it home without incident.  As for the question of why with regard to the shape, it will actually be more like a square with one corner severely chopped off, but the back corner remains. I intend to have 5 posts total if I can get the back corner worked out. The 3 corner posts forming the triangle, and two more coming back in to the center from the outside corners. Back to the why, it is due to the shape of my yard and the pool. A square would have to be pretty small in order to not look weird with the pool, and a rectangle would need to be angled in the corner instead of being parallel to my fences. That leaves me with shapes that involve tying in to a post from more than one direction in the same horizontal plane.


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## GBrackins (Apr 26, 2012)

sounds good ..... when I read triangular I was thinking equilateral triangle with each corner being 120, seeing the photos makes a lot more sense now ...... 

looks like a fun project! appears all corners are square and supported by lateral bracing and the angled piece just attaches at the lateral bracing.


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## funfool (Oct 5, 2012)

sway with the wind.
Does not matter if you have a 3 legged pergola or a 4 legged one, they need attachment. I can show you photos, and I can assure you the photos you just shared, blow in the wind and will not last.


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## SaintDonan (May 10, 2013)

Funfool, pardon my skepticism, but are you saying that no one is capable of engineering a pergola to not sway in the wind unless it is attached to a house or something? Or are you saying it needs more then 4 posts in order to do so? As previously posted, mine will have 5. If you are stating the former, it seems that the image below even though only partially built would be significantly stable by the time the rest of the bracing and the rafters where put on top.










http://stonesandtimber.com/wp-content/uploads/2011/01/Grape-Pergola-21.jpg


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