Preparation

• 1). Contact the county or zoning officials in your area and ask if a permit is required for building the type of structure you are planning. You don’t want to go through the trouble of building it only to be ordered to tear it down by code enforcement.
  
  
• 2). Measure the length and width of each of the 28 pallets. Ideally, they should all be close to the same size. In this barn, nine pallets will make up the floor, with each of the three walls being two pallets high and three pallets long. The total number of pallets needed is actually 27 for the structure, with an extra one that you will use when the main structure is complete.
  
  
• 3). Locate an area that is level and free of obstructions from low-hanging tree branches and roots that may make digging difficult. If you can't find a level surface area, you may choose to have a professional company come in with leveling equipment.
  
  

Begin Building

• 1). Dig a hole with the post-hole digger 4 inches wide and 2 feet in depth at each of the four corners where the barn will be built. Dig an identical hole in between the right-front and right-rear corners. Repeat for the right- and left-rear corners and the left-front and left-rear corners for a total of seven holes.
  
  
• 2). Lay the floor of the barn by placing the first nine pallets, three rows of three pallets each, onto the leveled surface. Line up the pallets so that the space between the pallet boards is directly over the holes you dug.
  
  
• 3). Insert each of the wall support beams, the 2-inch-by-2-inch posts, through the space in between the pallet boards and into the holes you dug. There should be a support beam at each of the four corners and three additional beams in the center of the corner supports for a total of seven support beams. Check the level of the support beam. Pour cement into the hole. Repeat for each of the six remaining holes. Allow the cement to dry overnight.
  
  

Building the Walls

• 1). Tilt one of the pallets upward so that the open space between the top surface of the pallet and the bottom surface of the pallet is exposed. Lift it up and over the left-corner support beam so that the support beam is sandwiched between the top and bottom surfaces of the pallet. Rest this pallet against the floor foundation and connect to the support beam by driving several 3-inch self-tapping carpenter's screws through the pallet and support beam on both sides.
  
  
• 2). Repeat this step with eight of the remaining pallets to form the bottom section of each side of the barn wall.
  
  
• 3). Repeat these steps to complete the top section of each side of the barn wall. Drive at least one screw in every 3 inches up the height of the support beams. For extra support for the top section, drive screws in from both the inside and outside of the structure through the support beam.
  
  

Finishing Interior Walls and Floor

• 1). Hold one of the 2-inch-by-4-inch-by-8-foot boards against the left inside of the barn structure at the seam where the bottom section of the pallet wall meets the top section of wall. Have a partner help you hold it in place. Drive one 3-inch self-tapping screw every 3 inches through this board into both the top and bottom sections of the wall.
  
  
• 2). Repeat the previous step with the rear- and right-side walls. These interior boards can be used to support shelving.
  
  
• 3). Lay the plywood pieces down on top of the floor pallets and secure them using screws.
  
  

Building the Roof

• 1). Take the last pallet you have and remove the lateral slats that are nailed to the 2-inch-by-4-inch boards. You can use a hammer with a claw or a pry bar.
  
  
• 2). Cut 6 inches off the length of each of the 2-inch-by-4-inch boards at a 45-degree angle. Form a ramp shape with a board by inverting the 6-inch length and connecting it to the longer section you cut it from. Use two 3-inch self-tapping screws. Repeat this step with the other board.
  
  
• 3). Use screws to secure one ramp at the top-left corner of the barn wall. The ramp should slant back to the rear of the barn. Repeat this step for the top-right corner.
  
  
• 4). Lay the piece of aluminum siding over the top of the barn and nail the siding to the top edge of the ramp and along the left-, right- and rear-side walls. Your barn is now complete.