Good planning is an important part of all successful construction work, but it is especially critical in tilt-up construction if the many inherent economics of this technique are to be realized. A carefully worked out schedule of operations is essential to ensure that the proper sequence of panels is ready for the tilt-up process. A casting layout should be drawn prior to construction to determine proper use of space and access for material and equipment. The floor slab must be level and smoothly troweled. If the floor contains openings for pipes or other utilities, a three-fourth of an inch skin coat over sand fill can be used to close up the openings temporarily. Smoothness is important in preventing mechanical bond and its necessary for clean cleavage when lifting. One of the obvious advantages of tilt-up wall construction is the savings in form material and labor. Panel edge form, which are relatively simple examples of form work, should be securely bolted or weighted down to the casting surface. Top and bottom edge form sections need to be braced and squared. If side forms contain holes for rebars, these forms usually are split 2 by 6's to facilitate stripping. The usual building code requirement for wall reinforcement calls for a steel area .0015 to .0025 times the area of the concrete in cross-section. Number 4 deformed bars 16 inches on center for a 6 inch panel are common. Around openings, number 5 bars are added to strengthen the corners and edges. The concrete is placed the same way as in a floor slab. Curing is started as soon as finishing as possible without surface marring. The size and placement of lifting inserts will depend on the size and shape of the panel, the surface design and the casting method. Cables for lifting slings need to be long enough to provide at least a 60 degree angle from the plane of the panel, and the rigging design should provide approximately equal stress on all inserts. The method of erection will depend largely upon two factors: whether the crane can operate on the floor slab or must stay outside the perimeter of the building; and whether the panel is to be cast up or face down.