The sub floor has just been poured in my house. I told the person who was taking house up to subfloor level that I needed 6 inches from subfloor to finished floor as I was putting in underfloor heating. When I measure from the subfloor to the top of the block it only measures 2 inches. I thought that the top of this block would be where the finished floor should be or will another block be built on top of this for the finished floor.