The successful construction of an elevated concrete slab requires planning, attention to detail, and a good monitoring program. A pre-pour conference is a good idea for ensuring a good quality concrete. Use this time to set a target slump for the batch plant. Consider a target slump that is 1 inch below that needed at the jobsite. This would allow material that arrives at the high end of the 2-inch slump range to be used without modification. Also, develop an elevation control checklist to help find and correct problems, such as misaligned rebar, forms, and beams, before the concrete is placed.
Contractors must understand the conditions affecting the window of finishability, which is the time period that finishers have to work with concrete before it sets. Finishing operations for elevated slabs don't differ much from those used for slabs on grade. It may be a good idea to consider using rigid screeds instead of wet screeds because the desired elevations are more easily maintained. Also, a rigid screed can be easily adjusted to increase the slab thickness in isolated areas where structural deflections are greater than anticipated. Using a straightedge instead of a bullfloat can provide up to a 50 percent improvement in floor flatness.