Can improper compaction ruin your concrete floor? Do you know what to look for when the masons come to pour your concrete? There are many things you could use under your concrete floor and proper compaction is key to you getting a nice floor that will last a lifetime. Cut corners on what's under the concrete and you will have a floor that will crack and separate. I am a firm believer that the prep is more important than the concrete on top. Watch this video and I can show you a disaster waiting to happen.