One way that you can really mess up an estimate is by assuming that the floor to ceiling height is all the same. Checking the sections of the building really comes into play when you are working off of the mechanical, plumbing and electrical drawings. When you are routing the pipe or conduit you really need to know how high the ceilings are. You can run into a multi story atrium or gymnasium and that will make your runs of pipe or conduit longer. Also if you are running underground or under the slab and there happens to be a partial basement you will either need to change materials or route the pipe or conduit around the area.
When I start to takeoff I will review the plans and highlight the areas that have different heights so when I am doing the takeoff I can either rout the items around the area or account for the changes in the quantities. Highlighting different areas also works for work on buildings that have different space requirements like jails, classified work and medical facilities.
Taking just a few minutes in the beginning to review and understand your plans can save you a lot of headaches and hassle later!
