My name is Giulliano Prieto, general engineering contractor with Prieto Engineering in Los Angeles, California, and today I will show you how to install an interior concrete floor. For purposes of demonstration, I will use this square board as the perimeter of the home. Now, the first step in installing an interior concrete floor, is to ensure that we are protected against any moisture. Now, the first step is to place a layer of sand, anywhere from an inch to two inches should suffice. The next step is to place six millimeters of plastic or greater over the first layer of sand. Once this protective barrier has been placed, then we're ready to install one more layer of sand, again about an inch to two inches. This will ensure that the barrier is protected against any construction or construction debris as well as evening out the subgrade under the concrete to be placed. The next step in installing an interior concrete floor is to ensure that you have some reinforcement. Reinforcement varies. You can do fiber mesh which is fiber inside of the concrete. In this case I have wire mesh which is welded wire fabric and also you can use rebar. All these things may be specified by the architect or the engineer which has designed the house or standard building codes. Place the wire mesh into the interior of the home. If using wire mesh, you'll want to ensure that you have at least two squares of lap for a six inch by six inch square matte. Following the placement of the reinforcement, you'll want to raise it off of the sand so that concrete can go below it and over it. Typically you'll want to have the wire or the reinforcement at the mid level of the concrete. When placing these concrete dobies, you'll want to just twist them, just enough for the wire to not shift around over the dobie. At this point, our reinforcement is completed. Once all the appropriate inspections have occurred either city inspections or through structural observations, you're now ready to pour the concrete. We have our Visqueen in place. We have our sand in place, our reinforcement and now I have here some concrete that we're ready to put down on our interior floor. For this demonstration, I just have it in the wheelbarrow and we'll begin placement. The next step in the process is to level out the concrete. I'm using a 2 X 4 as a wood screed. The final step in installing an interior concrete floor is to trowel finish it. You may want it troweled smooth to apply a stain or you may want to broom finish it to apply tile. There is various methods to finishing concrete so check with your architect or engineer as to what the specifications may be. My name is Giulliano Prieto with Prieto Engineering, and I thank you for watching my video and learning on how to install an interior concrete floor.