Flying Form Design Calculator
Calculate table form dimensions, weight, crane requirements, and cycle time.
About this calculator
Table Area scales directly with Bay Width and Bay Length -- shrinking either dimension by a fixed 2 to 2.5 ft clearance margin -- and Table Weight and Crane Pick follow the same area scaling through Form Weight per sq ft. Story Height is declared as an input for "the flying form legs," but this calculator never actually uses it in any calculation: Table Area, Table Weight, Crane Pick, Cycle Time, and Total Project Duration all come out identical whether Story Height is 8 ft or 25 ft, so it's informational only here. Cycle Time itself is a fixed 1.3 days (strip, fly, set, pour, cure hours summed) that doesn't respond to ANY input -- not bay size, not slab thickness, not floor count -- so Total Project Duration is really just Number of Floors multiplied by that constant: 1 floor takes about 1 day, 10 floors about 13 days, 100 floors about 131 days, a purely linear relationship.
Labor Savings vs. Conventional is likewise a fixed 50% industry-average figure baked into the formula, not something this calculator recalculates from your specific inputs -- treat it as a general planning assumption rather than a project-specific estimate.
Inputs
Results
Table area (sf)
714
How to Use This Calculator
- Enter Bay Width and Bay Length in feet along with Slab Thickness in inches.
- Enter the Story Height and total Number of Floors to estimate the full project scope.
- Review Table Area, Table Weight, and Crane Pick weight in tons to verify crane capacity.
- Check Cycle Time in days and Total Project Duration to schedule the pour sequence.
- Use Labor Savings vs Conventional to justify the investment in flying form systems.
How the result changes with Bay width (ft)
| Bay width (ft) | Table area (sf) |
|---|---|
| 14 | 322 |
| 21 | 518 |
| 42 | 1,106 |
| 50 | 1,330 |
What each input means
- Bay width (ft)
- Width of the structural bay (column-to-column).
- Bay length (ft)
- Length of the structural bay (column-to-column).
- Slab thickness (in)
- Thickness of the concrete slab.
- Story height (ft)
- Floor-to-floor height for the flying form legs.
- Number of floors
- Total number of elevated slabs to form.
- Form weight (psf)
- Weight of the flying form table per square foot. Typical: 12-18 psf.
What each result means
- Table width (ft)
- Flying form table width (bay width minus clearance).
- Table length (ft)
- Flying form table length (bay length minus clearance).
- Table area (sf)
- Surface area of one flying form table.
- Table weight (lbs)
- Weight of one flying form table.
- Crane pick (tons)
- Total crane pick weight including rigging (10% added).
- Total load on table (lbs)
- Combined dead + live load on one table when concrete is placed.
- Concrete per bay (cy)
- Cubic yards of concrete per structural bay.
- Cycle time (days)
- Estimated cycle time: strip, fly, set, pour, and cure.
- Est. project duration (days)
- Estimated total project duration for all floors (one table set).
- Labor savings vs conventional (%)
- Estimated labor savings compared to conventional hand-set forms.
How this is calculated
Worked example, using the default values
- Identify Input Parameters4 parametersBay width (ft) = 28, Bay length (ft) = 30, Slab thickness (in) = 8, Story height (ft) = 12 = 6 input(s) provided
- Calculate Table areaTable area = tableWidth * tableLength714 = 714
- Calculate Table widthTable width = bayWidth - 2.525.5 = 25.5
- Calculate Table lengthTable length = bayLength - 228 = 28
Engine last updated . Checked against 3 independently-derived tests — how we verify calculators. Built by Paul Gunder, a software engineer, not a licensed financial, medical, or legal professional.
Frequently Asked Questions
Does Story Height change the table weight or crane pick weight?
No. Story Height is not referenced anywhere in this calculator's formulas -- Table Weight, Crane Pick, Table Area, and every other output come out identical whether you enter 8 ft or 25 ft. Only Bay Width, Bay Length, and Form Weight per sq ft affect the table's size and weight.
Why does Total Project Duration only seem to depend on Number of Floors?
Because Cycle Time Days (the strip/fly/set/pour/cure sequence) is a fixed 1.3 days in this calculator, regardless of bay size, slab thickness, or any other input -- it never changes. Total Project Duration is simply Number of Floors multiplied by that constant, so 10 floors runs about 13 days and 100 floors runs about 131 days.
Is Labor Savings vs. Conventional calculated from my specific bay size and slab thickness?
No -- it's a fixed 50% figure based on industry-average labor hours per sq ft for flying forms versus conventional hand-set forms (0.06 vs. 0.12 hrs/sq ft), the same regardless of any input you enter. Treat it as a general planning assumption for comparing form systems, not a project-specific calculation.
How much does Bay Width actually change the crane pick weight?
Directly -- Table Area scales with (Bay Width - 2.5) times (Bay Length - 2), and Table Weight and Crane Pick both scale linearly with Table Area through the Form Weight per sq ft input. At this calculator's other defaults, moving Bay Width from 10 ft to 46 ft moves Table Area from about 210 to 1,218 sq ft.
Related Calculators
The questions that sit next to this one — chosen by subject, including calculators filed under a different category.
Shore Tower Design Calculator
Calculate shore post spacing and load from slab thickness and shore capacity.
FormworkReshoring Calculator
Calculate reshore spacing and loads for multi-story concrete construction.
FormworkWall Form Pressure Calculator
Lateral concrete pressure from pour rate and temperature per ACI 347R.
Manufacturing OperationsTakt Time Calculator
Calculate production takt time from available working time and customer demand to synchronize your production pace.
PlasticsInjection Molding Cooling Time Calculator
Calculate cooling time using the flat-plate analytical solution: t = (s²/(π²·α)) × ln(8(Tm−Tw)/(π²(Te−Tw))). Determines total cycle time and production rate.
More in Construction & Building Trades.