Floor plans are a form of orthography projection that are used to show the layout of rooms within buildings or interior spaces as seen in the picture here. For plan shows you were the new walls or new construction will be placed in the home. They help you see the proper flow within your space so that things are put in its proper place.floor plans are prepared as part of the design process to provide instruction for the new construction that will take place on the job site, leaving no room for mistakes when it comes to the flow of the home.