mook johnson wrote:
"mike" wrote in message
...
I notice the old fences around all have 2 horizontal rails for the
boards to attach to. I've also noticed that new specs often show 3
rails, without comment. I'm thinking that this might be due to the
fence boards being much thinner than they used to be.

I like to place my rails long side vertical, so I don't get excessive
sagging over time. But I'm thinking that unless I expect the fence
to see hard wind loads or other severe attacks (kicks, etc.), 2 rails
might be enough.

Any thoughts?

I've seen fences installed after Huricane Ike hit down here in
Houston and the ones with two rails have boards warping and bowing
like crazy. I mean every board is going a different direction. This
is in more than just one neighborhood so it looks like the quality of
fence board in general has gone down. 3 rails (top middle and
bottom) may help with this warping issue.

My house backs up to a 200' wide power-line easement. The houses on my side
of the easement all had their fences installed with metal posts. No a single
fence came down during hurricane Yikes! The houses on the other side of the
easement all had wooden posts. Almost all of them were flattened.