I'm building a 8'x8' chicken coop (this is my first time building a structure, most my prior carpentry experience has been limited to furniture, shelving, and benches). The floor joists will be 2"x6"x8' and the floor will be 3/4" OSB. To elevate the floor off the ground I'm putting down concrete deck bases/piers (resting on the ground, not buried in it) with a 4"x4"x1' post sticking up from the base. My questions is, what is the best method to secure the 2"x6" joists to the 4"x4" posts? Should the corner of the floor joists sit on top of the post, or should the posts be inside the corner joists and bolted to it? Or, should the posts be notched to sit snugly with the corner joists?

Here is a rough (unmeasured) sketch of the floor/joists and posts (it's upside down for ease of looking at it). In the bottom right corner would be the 4"x4" posts inset inside the joists. In the top right corner, the 4"x4" posts sits on top of the joists.


Here is the same thing, different angle showing the inset posts would be secured with a heavy duty bolt (bolt hole not to scale, of course). My concern with this is it isn't transferring the weight of the coop to the 4"x4" post as much as it would be to the bolt (i.e. the bolts on the four corners would be carrying the full weight of the coop).


And my third option would be to notch the 4"x4" post like in this picture so half of it would rest on the corner joists and the other half inset against the OSB. My concern with this is now the weight of the coop is on just the outer 2" of the 4"x4" posts, and the remaining 2" notch seems fairly weak.


So, what is the best, strongest, and most secure method to attach the 2"x6" joists to the 4"x4" posts?

Thanks!

Set them inside not on top. Or better yet why not look at running your 4 x 4 all the way to the roof. Lots of support that way.

This is true. But, I was trying to make this construction as easy as possible (on me) being this is my first time building a structure.,The plan was to build the floor, sit it on top of the deck bases/piers elevated to 20" via the cut 4"x4"s, and on top of the deck just erect four walls using typical home building wall framing methodology (using 2"x4"s). Then add a stick built roof at a 45 degree angle. In essence, a simple square 8'x8' shed.

^^^^^^^^^^^^^^^^^^^This is what I did..

I have built coops both ways you have described and have decided it is easier  and less lumber involved to set structure on the post rather than run the post through the structure.  I use metal plates to mount structure to the post. I use a slant roof for all my outside structures though, I have run the numbers and I am able to save a few dollars by not having a pitched roof.  Less material involved with a sloped roof. Spend the saved money on more important things  
just my .02

Thanks, so how do you attach the floor/joists to your posts? You mentioned metal plates, but could you elaborate?

The plates are made by Simpson Strong Tie.  The plate screws to the post and the floor framing will sit within the metal plate.  Simpson makes many different plates that would work. If you go to home depot website and type in, Model # LPC4Z, those are the plates I use.  I am located on top of a hill without any wind block and I have yet to have anything blow over. My largest building sitting on top of post is 10x20 and the smallest being 8x8.
Hope that helps out

I'd reconsider the OSB for flooring.  Unless you get all OCD about changing out the litter, the floor will get damp.  You'd be better off with exterior plywood, unless you're planning on covering the OSB with vinyl flooring or something.

Thanks for the advice. I am planning on laying down flooring (was thinking linoleum like what is used in bathrooms or kitchens). I'm not 100% sure what bedding material I will go with for the coop floor. We have horses, so we always have lots of pine shavings. But I've read sand is a great material to use for this.

Like minds think alike, apparently. Those are the exact same brackets I picked up when I got the wood last week.

Just notch the 4x4s as you sketched out.

And I would still go with an exterior grade plywood (or Advantech T/G floor sheathing) even if you are covering it to avoid excessive edge swelling, etc.

good call.

I recently bought a place with a coop and last week cleaned out about 12-14" of straw and shavings.  It was still saturated with urine even after 3 months of being unoccupied over the winter.  Lots of liquid will be present.   My floor has lino and is torn in a couple spots.  I am wanting to put another lino layer on for easy cleanup and protection from soaking the plywood floor.

Dude, just about every deck in America have the posts inset into the rim boards.  It's the normal way to build things like this. The reason you think yours looks so strange is because your run board is the same size as your joist.

But I would run the posts up to the roof.  You can then attach sheathing to them.

But above all else.  It's a f&cking chicken coop.

Dammit,.... realist!

I had to look that one up. Found a nice source here. So, I'm going to go pick up two 4'x8' sheets of plywood for the floor, any recommended thickness? Also, is OSB still okay to use for the walls and/or roof? I will be adding siding and asphalt shingles to the roof to keep the water out, but we do gets loads of rain, and humidity during the summer, so using OSB anywhere is of concern. Reason I was using it is because I already have four 4'x8' sheets of it left over from a previous project.

I'd guess OSB would be OK even for the floor, if you're planning on covering it with linoleum like you mentioned earlier.  But exterior plywood would give an extra level of protection.

Can you expand on this? Its a foreign language to me. What is a run board? How should it be done?


a) I am of the "if your going to do a job, do it right and on the first try" mindset, and
b) I'm using this as a learning experience for future projects so I want to learn how to do it right

Autocorrect got me.

You have a header joist or rim board or whatever you want to call it that holds the ends of the joists and actually supports the structure.  On anything with weight this needs to be sized appropriately along with the joists since it is basically carrying the whole load, the joists are just big enough to not deflect. So naturally it is usually beefier than the joists.

I would size up the rim to like a 2x8 so I could put two bolts with some spacing through the posts.  This also helps keep the posts straight for some lateral bracing.

I would not notch the posts because  then all you lateral stability is based on what's left of your posts (2x2), not that great. Plus the pita of attaching it. Plus you better be good with a saw if you are not table sawing this.

Lastly I would run the posts up to the top and do some banding with 2x like you would a pole barn.  Then the 4x4 has the entire height of the coop to keep it straight and strong.

Anytime you can use a longer piece and have it braced more is usually a good idea.  It won't take but a minute to notch the plywood for the 4x4s and you will save that time later because you can attach the sheathing right to the banding without thinking.

Great info!! Thanks. So something like this:



And I've got about sixteen (good shape) pressure treated 2"x8"x8'  from something I dismantled, would those be better to use with a 3/4" plywood floor? Hella heavy, but sure would keep the coop weighted down. Or should I use for of the 2"x8"s to make the header joists, but to lighten the load use 2"x6" for the joists (that run under the floor)? The more I think about it, the more I like the structural integrity running the corner 4"x4" posts all the way up provides (especially in a structure that is on posts not cemented in the ground), versus just a 1' 4"x4" posts from each deck base.

Also, what is the banding? I tried Googling that and it didn't turn up much in relation to construction and roofs.

Yeppers, just like that.  

I did painted plywood for ours, but I am no chicken expert.

Is the entrance going to be in the floor.  If so then some of the extra 2x8s could be used as header joists around the opening in the floor.

Have fun.

You lost me there. Entrance in the floor like a tree house where you climb up a ladder through a hole in the floor? I am planning on having the main door on one side, just like a house (though there will be a few outside steps to get up to the level of the coop floor) .

Also, any specific material I should use for the carriage bolts to attach the header joists to the posts? Galvanized okay? And any diameter best for carrying this load? 1/2"? bigger?

Thanks!

Holy cow, your CAD skills just got a lot better!!  

Some put the entrance in the floor and they hop up some steps to get in.  If you have a door in the side then never mind. I almost always use grade 8 or gavanized for outdoor stuff just cause it doesn't rust.  Galvanized is of course cheaper.  Some 1/2" or bigger would look good.

Really with 2x8s and half inch bolts your going for looks on this thing.  All of it is plenty strong.

I don't mean to go off topic and you may have already gave a good argument for using OSB in the thread, but I would highly recommend that you reconsider this. OSB is a great cost-effective, strong alternative to plywood interior spaces that are climate/humidity controlled. Over time in a poorly ventilated, moist environment (ie attics, outside structures, etc.), OSB is prone to delamination from mold and condensation. This is highly controversial, but just my .02.

4x4's with 1/2" galvanized thru bolts will work fine with the posts cut off under the floor.  You will only have to buy one 4x4 like this.  Just make sure you tie the wall corners together good.  

I just finished building one this past Sat.  





Still need to put the latch on the door in the fence and paint.

Thanks for the info! I'm trying to be as economical as possible and use materials I already have on hand. Last year I built two bomb-proof decks to store our winter hay on. They each were 8'x8 and built out of pressure treated 2"x8"x8' sixteen inches on center. turned out they sucked for hay storage because they didn't allow air flow under the hay. This year I'm just storing our winter hay on pallets. So I've got a lot of 2"x8"x8'. I also though the decking I used to cover it was OSB, checked last night and it is 4 sheets of 4'x8' 3/4" plywood. The only wood I've had to buy so far is the 2"x4" for framing, and the four 4"x4" corner posts. I will be using the 3/4" plywood I already have for the floor, and since that leaves me with two more panels I'm just going to finish the walls off with the same stuff (although I will have to buy six more sheets of it). For the roof, I will go with something lighter (either thinner plywood, or OSB).

Nice coop. Are your 4x4 posts in the ground a good few feet? The difference with my build is I'm not going into the ground, I'm going to be setting this on deck bases, and from there use 4x4 posts as risers. If I were to cut the 4x4 posts to one foot, even attached via brackets to the floor/joists, it doesn't seem as structurally stable compared to running the 4x4 posts all the way to the roof.

The one above looks really nice.

My last comment would be how many chickens are you planning?  An 8x8 is pretty freaking big for chickens unless you are planning on 15 or more IMHO.

We had 4 at one point in a 2x4 coop. They only go in there to lay eggs or if it is super cold out and if they are laying eggs they usually share only a couple spots.  A separate area for each of them is a waste, they will share intentionally.

I dug thru the topsoil and set a paver block on firm ground with the 4x4 on top of that.  The top of the block is 3" tops below grade and the coop is rock solid.  We had a very heavy wind a couple days ago and it didn't move any.  
It would definitely be a stronger build if you ran the posts thru the floor and all the way to the roof, but it will cost you more lumber in posts and 2x4's to fir out the posts on the corners. In my case I had all the material left over from jobs except for the siding.  Didn't have enough posts to go to the roof so I didn't.  

Broke ground on this project today! My in-laws are in town visiting so while my wife took my mother-in-law shopping I took advantage of having another set of arms to lend a hand and conscripted my father-in-law to help. My daughter also lent a hand. We got the base and floor joists done in about 60-90 minutes. I dug down just past the topsoil on the four corners and used a weighted tamper to get the ground good and hard. Then I laid down about 3"-4" of rock for drainage. I set the deck bases on that.

My little helper coming to show me some of the "cool" rocks she picked from the gravel I had just laid down for the bases.


Everything leveled and squared up. Done with work for the day! The four corner posts are treated 4"x4"s and will run to the roof. The floor joists are treated 2"8"8's I re-purposed from a prior project (a platform for storing our hay that I dismantled). The space under the coop is 20" clearance and will act as a shaded half of the run. Dimensions are 8'x8'.


Tomorrow I will add the two sheets of plywood flooring. I've got the walls designed and all my measurements set, but I need to make a run to the local Habitat for Humanity store to see if I can pick up some cheap windows and a door. I will post more pics as I get more done.

We are starting with 8 birds, but I want room to grow our flock.