How many support posts for raised 8x10 coop?

[chicharomirinda]

I'm working on the plans for an 8x10 coop to be raised 2 feet off the ground. Besides the 4 corners, how many additional support posts underneath do you think I'll need and is there anything else I should do for good support? I am planning to use 4x4 posts on concrete base. Thanks!

 

[chriscos]

It really depends on what you are using for the "beams" ( 2 x 6's?) and how much weight they will be carrying. You probably want at least 4 more, one in the middle of each span.

There is a table on this page. It is for decks, which is overkill for a chicken coop. But it will give you an idea on what to do if you want to make your coop super strong.

http://www.dulley.com/deck/deck01.shtml

 

[Toothless Willie]

Hey,

I may have as many questions as answers.

A concrete base? We use 4X4 posts but sink them in 16 to 18 inches of concrete. If this is an existing slab make sure the edges are thick enough to support the point load of the posts. A minimum of 4" but 6-8 inches would be preferable. You should also anchor the posts to the pad if this is the case.

Chriscos is correct. The four posts can reasonably bear all the load from the coop as long as the "beams" you use can transfer the load. Our coops are 4X8. I use one at each corner and one in the middle of the eight foot span. I then use 2X6 treated as an outer band and frame between with 2X6 at 16"OC. If this is similar to your intent I would divide the sides into two even lengths and place posts there.

To adequately support the full 10' without bending you would need a much heavier timber. either 2-2X6, or around a 2X10 or even 2X12. Usually "cut off" from the corner posts allow you to put inner posts in, so why not? In my mind a coop this big means you need to support your weight as well. In this case I would put a "header" across at the center post on the 10' axis dividing each side into 4X5 areas. Placing 1-2X6 eight feet long on either center post face will allow you to frame with 4' members at 2' OC using even board lengths.

Hope this helps,

structural wood design engineer in real life.

 

[chicharomirinda]

Thanks chriscos and Toothless Willy for your replies! by concrete base, i meant holes for the posts with concrete in them. i'm not up on all the construction lingo yet

I will definitely go for the heavier timber for the band and frame.