The need for a very low cost chicken coop brought me to this solution.
I needed very few tools and a lot of good old fashioned work. My son's were a great help in the disassembly of the pallets and the build was strictly by the seat of my pants with no more than a vision in my head.
Below I will illustrate and guide you through the process how I was able to turn my vision into reality.

Step 1: Pallet Disassembly

Striping the wood without it splitting apart is difficult with some pallets.
Careful work will help and will offer pallet pins for reuse.

Step 2: Walls and Floors.

Using the precut lengths of wood made building the structure much easier and eliminates a lot of cutting.

Step 3: Siding and Roof.

The reclaimed pallet boards made for a great traditional look for the siding. Again the rafters of the roof are precut lengths from the pallets, a few cuts later we had our roof structure.

Step 4: Door.

For the door I sided directly over the door opening, used wood screws to attach trim boards and simply cut it out.

Step 5: Hen Boxes

I did use some particle board I had laying around to form the box and then sided over to keep the old barn appearance. Using 2×2's as backing, the wood screws allowed me to build the boxes without actual framing.