I built the first wall yesterday. I wanted it to be portable so that I can move it around if necessary. So instead of building a concrete foundation I built one out of steel. The objective is to build the wall.
The wall is six feet long and four foot high. It has a two by six that is six feet long as a top plate.
As of right now, Feb 22, 2011, I can’t see a secure wall created with the recycled plastic blocks without rebar verticals. For this wall I placed two at each end spaced the same distance apart as the wire that is securing the blocks. I also placed two mid span that will fit outside of the plastic blocks.
The bottom course of blocks was placed on the foundation. Then I placed doubled fourteen gauge galvanized steel wire between the end rebar verticals. Each block was secured at least one to each doubled wire with a wire tie. Then I placed a doubled fourteen gauge glavanized steel wire across the mid span rebar verticals with the end to end wires passing between.
The wire ties to the blocks were the only wires secured tightly at this point. After two more courses were laid down on top of the bottom course I went back and pulled and tightened the wires between all the different rebars. This post tensioning step that is critical. The blocks are lightweight. They won’t stay in place without the wire. They won’t be secured in place without the tightening of the wires. Once the wires are tightened the wall becomes substantial feeling. I repeated the process of tightening the course two courses below as I added each new course.
There has to be a top plate for attaching the roof. The top plate is also critical for the recycled plastic block wall to make it more secure. I used screws into the steel when securing the top plate to the wall in this sample. In a concrete foundation there needs to be loops placed for securing the top plate to the wall.
I used the tensioning tool we designed to tighten the wires securing the recycled plastic blocks to tighten the top plate wire. The top plate wire goes over the top plate from one side of the foundation to the other. The effect is amazing. It is also necessary because the blocks are so lightweight.
I put some plaster on the wall to see how it would work. It will work great as you can see.