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I wanted to be able to let my cats out into our fenced back yard without worrying about them jumping over the fence or other cats getting in. My wife saw a system for sale on the Internet but I made my own for 1/4 of the price. Here's how I did it.
Step 1The Theory Behind the Fence
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In theory, cats will not climb a reverse overhang or jump out and over something when they can see straight down. I found the first part to be true so far, but my neighbor's cat definitely disproved the second part. The unwanted visitor managed to get in my yard, but he could not get out until I let him out and has not been back since.
By attaching plastic mesh garden fencing to my wooden fence, I have been able to keep my cats in and the neighbor cats out (for the most part).
http://www.feralcat.com/fence.html
What a cool thing for our cats!
I have done something similar to what you have done, except I have a problem with trees inside my yard and close to the fence (3 of them).
I have a U-shaped area and on the left & right sides, first I have to staple some mesh to the fence on the bottom (only because the fence has spaces in between that the cats can easily get through. Then near the top of the fence (5') I have screwed in 5 flagpole holders at intervals. After putting the flagpoles in the holders, I then staple gun more mesh at an angle all the way across and it works. The cats seem to look at it as a ceiling even though they can scale part of the lower mesh.
But I have run across problems with trees along the back fence. I do have some "tree-guards" on the big trees, but my cat can still scale the back fence and somehow get through a gap that may be created in the mesh I put there as a ceiling. Once he gets through he is able to walk across the mesh along the back fence.
This has been an problem on & off since for 6 months there is enough stuff there to prevent him from leaving the yard; then after a time, he may discover a small gap in the mesh that enables him to get through the mesh to the top (like now).
The only way I can see how he is escaping is to stake him out, but he is getting smart about when, where and how I'm watching him and won't do it unless he's sure I'm away from a window. Suddenly he's gone. And he can't come back the way he left because when he wants in, he's at the frbnt of the house waiting for me at the front door to let him in,
I've usually been able to find where the problem is, but I don't see anything yet. He's driing me nutz!
Thanks for the idea.
We just finished the cat fence and released the critters to check it out. Our most adventurous cat - Nemo, started climbing the fence post, stopped - looked up, and jumped back down. I considered that our first success. We will continue to monitor the cats for weak points, but if I was a cat I'd just give up and enjoy being outside.
Has anyone heard of raccoons coming over the fence?
but its a very neat Idea +1