I just completed a new chicken run, greatly assisted by an amazing and free 3d design program: Trimble SketchUp (formerly Google SketchUp). While it takes some time to learn (I'm still learning!), this program helped me visualize the chicken run as well as estimate the amount of materials I'd need to buy. Here's how I used it to create the run:
Previous runs either did not work (chickens squeezed out and flew over) or were hideously ugly. I resolved to design a run that was both aesthetically pleasing and practical. Inspired by A-Frame cabins of the 60s Kelly and I came up with this idea:
I took my A-Frame plans to a friend, John Zapf, who runs Zapf Architectural Renderings. He took some time out, literally, from rendering multi-million dollar buildings to help with my lowly chicken run project. He could see a few problems with the A-Frame idea immediately--wasted space on the side towards the fence, and a lack of continuity between the shape of the chicken coop's roof and the new run. Taking out pen and paper (sometimes the quicker option!) he sketched out a much better design:
I took John's sketch and entered it into Sketchup:
Being the low-tech bumpkin that I am, once I completed the run I was excited to see how much the real thing looked like the rendering.
SketchUp has some powerful features. There's a library of objects other people have already drawn for you that you can download for free. For instance, the fence and tree (the exact same species of tree in my backyard, by the way) were both in the SketchUp library. And, amazingly, you can drop your model into Google Maps and even figure out the shadow patterns it will cast in the course of a year.
I'd strongly recommend going through the tutorial videos before trying to use SketchUp (I didn't do this and wasted a lot of time initially).