Metal roof question in Southeast Florida- planning and drawing designs

[Chicken_man_J]

I'm planning to use corrugated metal on my coop. My coop's frame is under construction and pictures and updates are in my post "started on my coop today that is going to be on a 6x10 trailer. I have traded the 1/2 hardware cloth to 1/4 hard ware cloth with aluminum bug screening. The roof will be similar to a lean-to coop roof. I have seen different designs from open purlin to purlin with plywood on frame then metal screwed to that. My concerns are the heat, rain and hurricanes. Will continue to post updates and pictures. Has been raining like crazy and plan on working on it. Have installed wood floor with vinyl or linoleum on top. Additionally, designing internal nesting boxes have collect oak limbs for perches. Any input will go into my plans in finishing the coop. Thank y'all and looking for comments and suggestions

 

[Saveria]

You could potentially check the Florida state page to ask what other folks are doing to have good strong roofs. I'm sure our rain up here could be comparable, but not the wind.

https://www.backyardchickens.com/threads/florida-always-sunny-side-up.305793/

 

[Chicken_man_J]

You could potentially check the Florida state page to ask what other folks are doing to have good strong roofs. I'm sure our rain up here could be comparable, but not the wind.

https://www.backyardchickens.com/threads/florida-always-sunny-side-up.305793/

Thanks for letting me know. I might post in there what I posted on here to get advice and input.

 

[Audi0]

We used plywood with metal on top. Also used hurricane straps on everything. This is 1st summer with it. Even tho we not hit the hottest days yet so far it’s been great. Lots and lots of ventilation is key. I was trying to find pics of between roof build but can’t seem to find them. Also added shutters to close for hurricane but keep for extra air flow it also helps with all the sideways rain. Used sooo many screws on roof that we had to put cork on the nails sticking down. Probably overkill but it’s super solid.

 

[3KillerBs]

I have traded the 1/2 hardware cloth to 1/4 hard ware cloth with aluminum bug screening.

What predators do you have? 1/4" hardware cloth is made of thinner wire and not strong enough to resist dogs, raccoons, coyotes, and other stronger predators.

My concerns are the heat, rain and hurricanes.

The solution to the heat is extreme ventilation. I STRONGLY recommend and Open Air design for anyone in climate zone 8 and above and think that it's often a good choice for zone 7 as well.

Repecka Illustrates Coop Ventilation
Hot Climate Chicken Housing and Care

If you can locate your coop in deep natural shade that's best, but if you have excellent ventilation under the roof it can be, like my big coop that's shown in the article, the coolest place in the yard even in full sun.

The solution to rain -- especially if it comes sideways -- is to orient your coop to turn it's back on the usual winds and to provide generous roof overhangs.

Raw size helps too and Open Air coops with deep litter over dirt are forgiving. The coop in the hot climate article is 16x16 not counting the roof overhangs so when rain penetrates a few feet into the open section there is still plenty of dry shelter and massive ventilation to dry things out afterward.

But Camp Cockerel also protects the birds adequately and dries out appropriately in short order.

Hurricanes are a matter of good construction techniques. Use hurricane ties for the structure, anchor it properly so it doesn't roll, and have enough threads of the screw through the purlins. @U_Stormcrow has an illustration of this that I hope he'll share here.

 

[U_Stormcrow]

This is the post in question.

This is something I threw together in a weekend.

Another comment post

Really good technical reference.

KEY Illustration

Hope that helps.

Things to remember.

ONE} You are building a chicken house, NOT a people house. The contents are less valuable, you don't need to overkill the design.

TWO} Most Chicken coops are SMALL. (compared to a people house). That means that, in spite of all the airflow we like in them - particularly Gulf coast and southern eastern seaboard - there's not a lot of square footage for wind uplift on the underside. That ultimately helps us.

THREE} Really expensive, really well built people house FAIL all the time. Usually due to installation mistakes, not materials failures. Watch some videos, read the MFG instructions, do it right the first time.

FOUR} Mother Nature is a a B. Eventually, something will happen, you WILL have a failure. Design/Build so you can see failures early and fix them before lots of damage is done - and consider building with an INTENDED failure point.

My goat shed is a good example. Setting all thoses 4x4s alone w/o power tools correctly was a beast. With enough wind load, its possible they could be ripped from the ground, and lumber is damned expensive (or was). At 100 mph, wind uplift is around 25#/sq ft. Doesn't sound like much, I know, but consider that a 2x8 sheet of corrugated roofing is 16 sq ft - in theory, 400# of force can be applied by a wind hitting it directly. There are ten sheets on my goat barn - 4,000# of force. Suddenly, 160# of concrete on each 4x4 post (6 total) doesn't sound like so much...

My hope is that, because of the very tiny (relatively speaking) size of the head - even on a #12 screw and washer - if I get forces strong enough to try and rip the whole structure from the ground, they will instead pull the steel right off the roof by ripping holes where the screws are located. I can re-roof in an afternoon. I might even be able to save sove of the damaged roofing, and I can repurpose almost all the rest.

I **could** have added a lot more deck screws, ensured the roof didn't fail. Then my next failure point would be the purlins - because all that force on the roof is being transfered to the purlin attachments to the rafters. The rafters are hurricane tied - they are going NOWHERE unless the whole structure comes out of the ground.

 

[aart]

My coop's frame is under construction and pictures and updates are in my post "started on my coop today that is going to be on a 6x10 trailer.

https://www.backyardchickens.com/threads/started-on-my-coop-today-that-is-going-to-be-on-a-6-x-10-trailer.1578351/

 

[Chicken_man_J]

Got to work on the coop today prior to thunder and decided to cover and tarp in case of rain. Pictures are of linoleum on floor, front of trailer on tongue side side with board removed then frame installed with ventilation setup up. Will continue updating build. Rowdy came up to enjoy shade!