Here's my PLAN for a 16- X 16-foot, predator-proof run.

[joebryant]

This summer I hope to build a separate coop for my silkies. Here is how I will make SURE that no predator can break into their run/coop area.
1. Make a 16- X 16-foot perfectly FLAT/LEVEL area on the ground.
2. Lay four 16 foot 2" X 12"s around the perimeter of area.
3. Lay concrete stepping stones 1/2" apart (for drainage) on the entire floor.
4. Fill the entire enclosure with contractor sand to the top of the 2" X 12" frame.
5. Attach 8 foot 2"x4"'s every four feet around the perimeter's 2" x 12" frame and across the top of the run.
6. Run 4 foot 1/2-inch hardware cloth going up the two by fours and across the top; attach it with screws and fender washers.

 

[WV_Hillbilly70]

Sounds like a great plan Joe. Post some pics of the build process...always in the market for ideas for my next coop

 

[patandchickens]

Quote:
Tthree issues here, the second and third quite important.

First, normal p/t lumber is not rated for burial. It will begin to rot when half-buried in sand like this, so it will not last as long as you THINK it will. (How long? I dunno, the new type hasn't been around long enough for me to get much experience with that type behavior; but even the old ACQ, which was much more rotproof, you would expect to start rotting after 5 yrs or so of part-burial)

Second, the weight/pressure of all that sand (or any other fill) is going to SEVERELY bow out your 2x12s, probably break them in time and certainly rip them off whatever posts they're attached to. You need to research the topic of making *large* raised garden beds and revetted embankments, because that's essentially what you're doing.

I would not try it with mere 2" lumber myself, I'd want something thicker; but in either case, you will need a number of posts set VERY SOLIDLY into the ground every 4' or so on the OUTSIDE of the grade board, and for that kind of weight with just 2" lumber you will probably also want the middles chained back to each other or to earth anchors (such as a buried tire).

And third, you will need MUCH stronger support for your pen top than just 2x4's on 4' centers with a 16' span. Especially if you are using hardwarecloth, which forms essentially a solid roof when snow gets on it. You need stronger (wider) umber AND closer together; and I would highly, highly, highly recommend crosspieces (purlins) to decrease sagging of the hardwarecloth and thus reduce its likelihood of getting ripped completely off under the weight of the snow.

Just sayin', good luck, have fun,

Pat

 

[PineappleMama]

#5 Be sure you get 2x4x8 and NOT studs... those aren't 8 feet. Lesson learned.

#6 Worked wonderfully well for us!

 

[joebryant]

Quote:
Tthree issues here, the second and third quite important.

First, normal p/t lumber is not rated for burial. It will begin to rot when half-buried in sand like this, so it will not last as long as you THINK it will. (How long? I dunno, the new type hasn't been around long enough for me to get much experience with that type behavior; but even the old ACQ, which was much more rotproof, you would expect to start rotting after 5 yrs or so of part-burial)

Second, the weight/pressure of all that sand (or any other fill) is going to SEVERELY bow out your 2x12s, probably break them in time and certainly rip them off whatever posts they're attached to. You need to research the topic of making *large* raised garden beds and revetted embankments, because that's essentially what you're doing.

I would not try it with mere 2" lumber myself, I'd want something thicker; but in either case, you will need a number of posts set VERY SOLIDLY into the ground every 4' or so on the OUTSIDE of the grade board, and for that kind of weight with just 2" lumber you will probably also want the middles chained back to each other or to earth anchors (such as a buried tire).

And third, you will need MUCH stronger support for your pen top than just 2x4's on 4' centers with a 16' span. Especially if you are using hardwarecloth, which forms essentially a solid roof when snow gets on it. You need stronger (wider) umber AND closer together; and I would highly, highly, highly recommend crosspieces (purlins) to decrease sagging of the hardwarecloth and thus reduce its likelihood of getting ripped completely off under the weight of the snow.

Just sayin', good luck, have fun,

Pat

Pat, I agree with you about using 4"x4" posts every four feet rather than 2"x4"'s. Most of what you say though is overkill in my opinion, e.g., "the weight/pressure of all that sand..."; the weight of the sand will be on the stepping stones, not the 2x12's. As for the top, see my BYC PAGE.

 

[patandchickens]

Quote:
No, that's not the case.

When you put a 12" high elevated area of sand (or whatever else) within grade boards or any other low 'walls', it presses outwards as well as just the normal downwards weight. Rather powerfully.

You really do need to learn about the special issues involved in engineering this sort of thing, or it's all going to slump outwards under its own weight and push your 2x12s apart, soon if not immediately.


Pat

 

[Sonoran Silkies]

I would recommend 1/2X1 welded wire over 1/2" hardware cloth; the wire tends to be a heavier gauge, meaning stronger, even though the spacings are larger.

Make sure that where one panel of wire ends that it is firmly connected to a post, or if between posts that ever single hole is attached to the next; overlapping is even better.

 

[Stumpy]

Soundslike a fortress. I'll be expecting photos