Sanity check my 14x20ft half-roofed run plans please?

[Popsikle]

I have been tasked with building a chicken run for my wife girls this weekend and was hoping to get a sanity check or some solid advice on the build.

First, a little background... We live in the northern mid-Atlantic region in the "ok" state of NJ. Our property includes 4 acres of wet woods (there is a class A stream that runs through my property) which is home to many predators such as raccoon, fox, hawk, vulture, owl, snakes, etc. Last summer at one point there was 3-4 feet of snow on my roofs and we have been hit with tropical force winds from storms the last 3 seasons. TLDR : Any structure outside needs to be able to take a beating and keep a lot of animals out.

For this build, the wifey wants something that sort of matches the other things on our property so I am planning on 4x4 posts with a 2x4 24inch OC framing for the walls. Im planning on half lapping the posts with some lag bolts and using hardware cloth all along the framing section for the walls. All of this seems pretty straight forward but she wants at least half of the run covered with a roof and well, roofs are new to me lol. Looking at some of the other structures that her grandfather and father built on this property before we moved in, I picked up some 2x6 to use as the rafters. I plan to use 2x4 blocking and metal roofing that slopes from "front" to "back" of the pen to drain the water/snow towards the stream which is the natural direction of the water on my property.

Some questions I have:

• Does all of this sound like it will hold up to the elements?
• Am I over-engineering this? (I have been known to over-do things in the past lol)
• Because the frost line is 36inches, I want to avoid digging and pouring concrete for the corner posts, do you think I need to?
• If I don't bury the corner posts in the ground should I be concerned about the wind taking the entire structure even though the only solid bit is the roof?
• Do I need some sort of sheathing under the roof like osb or something?

Here is a quick drawing of the plan in my head, thoughts?

 

[DobieLover]

Something like this?...

That held up to this ?...

I used double 2x8 for beams front and back with 8' OC spacing then added 2x4 framing in between (for a final spacing of 4' OC) on which to secure the 1/2" HC.

 

[Popsikle]

Yea, pretty much, except a bit taller.

The original plan was 4x4 posts every 4 ft with 2x4 corner bracing and some welded wire/hog panel top plates but then she asked for a covered roof, and put me well outside my elements lol. I was originally not going to frame the walls with 2x4 but was concerned about shearing and snow load after watching waaaaay too many youtube videos on how to build outdoor roofed structures...

 

[3KillerBs]

Welcome to BYC. Over-engineering beats under-engineering -- though I say that from the perspective of a person whose brother-in-law designed airports and whose father believed that any structure not built to last 100 years was a temporary make-do.

DH and I found that metal roof installed over purlins with self-tapping screws was extremely easy and straightforward to install.

I highly recommend these electric metal shears for both the hardware cloth and the metal roofing (though if you can design it to not have to cut the roofing that's better).

https://www.harborfreight.com/18-gauge-35-amp-metal-shears-61737.html?_br_psugg_q=metal+shears

Don't be tempted to get the more ergonomic ones -- those take a kerf out and will salt your run with dangerous bits of metal that the birds will surely eat.

There are some photos of the roof for my new coop starting here:

https://www.backyardchickens.com/threads/large-open-air-coop-in-central-nc.1443812/page-12

 

[U_Stormcrow]

I think its overkill, and wind uplift is only a concern if your roofing material is strong enough to take those loads. If you use metal roofing (cheap, easy, fast, durable), it will fail either where the screws penetrate the purlins, or where the purlins are affixed to the rafters before it lifts any substantial weight. You aren't building a house for humans, you don't need to biuld as it if was one.

Now, lighter build means it should be affixed to the ground - but you can do that with a primitive earth anchor or screw in augurs at the corners to address wind concerns.

Frost heave (and the need for 3' deep footers) is a concern for concrete floors - strong in compression, very weak in tension - so when the ground pushes up from underneath and there is nothing but the weight of concrete to reisist it, it cracks. You aren't pouring a concrete floor in your run (or shouldn't, anyways), so frost heave is a much lesser concern.

Take a deep breath. Enjoy a beer. Look over your landscape, make sure it drains away from where you are placing the coop - that's hard to fix later. Done the beer? Satisfied with the landscape slope? Go find your eyes and ears and get to it - you got this!

 

[mowin]

I disagree with above. Your posts need to be below frost level. Not necessary to cement them in, but for a few extra bucks, I'd cement the corner posts. Also, why would anyone build anything with the thought the roofing will fail before the structure does? As far as metal roofing being "cheap", it's not so cheap, and if you have to replace it, not getting any cheaper, is it.
If properly fastened, the metal roofing won't fail, or lift in most winds. Mine hasn't lifted with 70mph winds doing it's best to succeed.

 

[U_Stormcrow]

I disagree with above. Your posts need to be below frost level. Not necessary to cement them in, but for a few extra bucks, I'd cement the corner posts. Also, why would anyone build anything with the thought the roofing will fail before the structure does? As far as metal roofing being "cheap", it's not so cheap, and if you have to replace it, not getting any cheaper, is it.
If properly fastened, the metal roofing won't fail, or lift in most winds. Mine hasn't lifted with 70mph winds doing it's best to succeed.

Metal roofing is cheaper than decking, papering, and shingling - more durable, too, and more likely to be installed correctly. We have differing wind concerns. I'm in FL - gusts of 70 mph isn't a concern - we see that with some frequency as part of regular summer thunderstorms. 100 mph+ is - I'd rather lose the roof and keep the structure than lose everything. That calculus chages, of course, based on the contents of the structure, but many commercial buildings are designed the same way in our region. A roof over an empty chick run is not a content I'm much invested in protecting.

Yes, longer 4x4s and a concrete bedding is a perfectly acceptable way of making an earth anchor.

(To answer your querry).

 

[Bigtom Turkey]

 

[mowin]

Metal roofing is cheaper than decking, papering, and shingling - more durable, too, and more likely to be installed correctly. We have differing wind concerns. I'm in FL -

A roof over an empty chick run is not a content I'm much invested in protecting.

OP isn't in FL, as you mentioned, different wind conditions. So why suggest he build something with a disposable roof?

Most do protect their investments, including a chicken run.

To the OP, build it once, build it right.

 

[U_Stormcrow]

OP isn't in FL, as you mentioned, different wind conditions. So why suggest he build something with a disposable roof?

Most do protect their investments, including a chicken run.

To the OP, build it once, build it right.

because even that "disposable" roof is likely to be more than adequate for his wind conditions?