I am building a chicken coop and I (read: my wife) wants to put a 'green roof' on it. I have already started building it, not planning on a green roof and I am wondering if the 4 - 2x4's that support the coop will be able to handle the weight of the roof.
I will put up a couple sketchup pictures of the framing I am using for reference. I have never framed anything before as will be readily apparent, but it is a chicken coop so I wasn't too worried, until the whole green roof thing came up.
So, the 2x4 corner posts are attached with two 3.5" bolts (each), face to face to the 2x6 'foundation' which is 4'x10' and resting on leveled brick pavers. The approximate dimensions of the coop structure are 3.5 l x 4 w x 6.5 h. In terms of weight, I have leftover 3/4" plywood that I am going to use for the walls and roof, when that runs out I will switch to OSB. So in all there will be approximately 3 full sheets of 3/4" ply and/or OSB on the structure. The green roof is going to be about 3-4 inches deep and should max out at no more than 400 lbs when wet.
Can it handle the weight?
I was thinking the quickest fix could be to cut the 2x4s at the floor of the coop and put it on 4x4 posts, attaching those to the 2x6's, but only would do that if it is absolutely necessary.
OR do you think I need 4x4 going all the way up to the roof?