# help with a curved pergola

## help with a curved pergola (post #91471)

Hi there,

I stumbled across this forum while searching for some answers to my project. I am a landscape architect and I would like to design a curved pergola as a feature element in my garden design.  However, I am uncertain how to build it and write the specs.  any ideas would be appreciated.

the beams for the pergola will be 2"x10" stk cedar and support a 2x8 arbor joist spanning 7.5'(the inside width of the pergola beams).  The beams will be supported by 10" round fiberglass columns.  the inside radius of the pergola beam is 13' with a length of 25' and the outside beam radius is 21' with a length of 32'. so basically i want to take an 7.5' wide pergola and bend it into an arc with an inside radius of 13'.  what do you think?

### (post #91471, reply #1 of 8)

I think it would be a very interesting project. I love challenges.

Are you talking about having the upper struts radiate out like equally sized spokes in a wheel from a central dome, or parrallel multilinear ones that cross over a curved beam? Is this to be a free stranding pergola or attached to a house?

In the attachment, look to the upper floor balcony right. You can see paired beams and multi length struts creating an angle. Something like this could accomadate a curved end to them without much trouble by cutting lengths of each different. There are four columns supporting two parrallel beams, though it is hard to see all four at the angle.

Supposing a curved beam and attachemnt to a house, you would need at least three columns because the center or a horizontally curved beam placed onto two columns at either end would obey the laws of gravity, unless you calculated placement to let a cantilever effect balance the curve on two bearing points.

Three columns is asymetrical and ugly in most applications, so four would be more appropriate.

Say more...

Have you any sketches to post?

.

Excellence is its own reward!

Oh Well,

We did the best we could...

PreviewAttachmentSize
kax_ext_pergolas.jpg29.92 KB

### (post #91471, reply #6 of 8)

i have a plan view drawing that i should post once i figure out how to post it.  It is a free standing pergola with the beams following the radius curve.  The joists set on top of the beams will radiate like spokes on a wheel as you noted. however the joist will not terminate at the radius point, they will be about 8' long.

### (post #91471, reply #2 of 8)

big ed.   from dallas built a nice one... showed us the pics about two years ago...anyone remeber that  ?

there are some famous  curved ones... where they are escapes me now...

Mike Smith   Rhode Island : Design / Build / Repair / Restore

Mike Smith   Rhode Island : Design / Build / Repair / Restore

### (post #91471, reply #3 of 8)

Italy, probably

I think one is one a pond north of Rome where Nero went for a picnic/orgy shortly after he burned the city. I don't know if it still exists or just in drawings still. I can see it in my minds eye.

.

Excellence is its own reward!

Oh Well,

We did the best we could...

### (post #91471, reply #4 of 8)

i think another one is in switzerland... in that park with all the statues... including one of Roger Williams... who was some  kind of hero to the swiss     for  his views of religious freedom   ( founding Rhode Island after escaping from the puritans in Massa chusetts )    ... small world , no ?

Mike Smith   Rhode Island : Design / Build / Repair / Restore

Mike Smith   Rhode Island : Design / Build / Repair / Restore

### (post #91471, reply #5 of 8)

Steve-

I agree it sounds like an interesting challenge. The kind of job I wish would fall in MY lap. The biggest problem, of course, is making straight wood curved. You would need to have cedar 2 X 10 resawn and thickness-sanded to end up around 3/8 " thick and glued up in your needed raddii. Then you need a form to which you would glue your strips. With for posts supporting the outside radius, each glue-up would need to finish out at around 10'-8" long. (I would go with four posts over the outside radius, and I suppose the inside as well. That way you don't end up with a post in the center. Dividing the space into three segments seems more aesthetically pleasing.) If I was doing it, I would build a structure for the form out of steel and face it with plywood, probably layers of 1/4". Then buy a ton of glue and 2 tons of clamps and go to town. As long as your going to be "inside" your 2 X 10's, why not rout a groove for wire and put insome really slick and nearly invisible lighting?! Now we're talking. And if you're looking for someone to do the work, yes, I'm interested!

### (post #91471, reply #7 of 8)

are you in the Olney, MD area? I actually pondered the use of steel, but got stuck on it. like your ideas. how do we explore them further?

### (post #91471, reply #8 of 8)

He's described the curving process well, though I would recommend epoxy instead of glue and the slices could probably be 1/2" thick for this radius.

You can scroll down in your reply window to hit the Attach files button and post your drawing in GIF, Jpeg, or Btmp. Odds are you can save your drawing in one of those formats from your drawing program. Follow the intructions carefully and thoroughly.

Or you can click on my name and choose email and send it to me and I can re-post it here for you from almost any format.

http://forums.taunton.com/tp-breaktime/messages?msg=20026.1

This is another thread that discussees pergolas in general. It has some photos and comments that might apply to any pergola and is worth your reading.

.

Excellence is its own reward!

Oh Well,

We did the best we could...