Scaffolding Calculator
This scaffolding calculator estimates the scaffold you need along a wall. Enter the wall length, the working height, and the scaffold type, and the scaffolding calculator returns the number of bays and lifts, frames, cross braces, planks, guardrails, toe boards, base plates, mudsills, and an estimate of wall ties, plus the scaffold face area for rental or labor pricing.
Results
The Scaffolding Calculator is part of our Materials Estimating collection. Browse more materials estimating to size, convert, and check your work alongside this tool.
What the scaffolding calculator does
A scaffold is built in bays along the wall and lifts up the height. Once you know how many bays and lifts the job needs, every other component follows: frames at each end of every bay, braces in each bay, planks on each working level, guardrails and toe boards along the open edges, and base plates and mudsills at the bottom. The scaffolding calculator divides the wall length by the bay length and the height by the lift height, rounds both up, and counts the parts.
Scaffold bays and lifts formula
From these the calculator counts:
- Frames = (bays + 1) × lifts
- Cross braces = 2 × bays × lifts (both faces)
- Planks = bays × planks per bay × working levels
- Guardrails = working levels × (2 × bays + 4), top and mid rail on the face and both ends
- Toe boards = working levels × (bays + 2)
- Base plates = 2 × (bays + 1), mudsills = bays + 1
Wall ties start where the height passes 4 times the base width, then repeat every 26 ft vertically and 30 ft horizontally for frame scaffolds, the OSHA maximums, or about 4 m and 6 m for system scaffolds.
Scaffolding estimate example
A 40 ft wall needs a frame scaffold to a 20 ft working height with one planked level and two planks per bay:
That is 28 frames, 48 cross braces, 12 planks, 16 guardrails, 8 toe boards, 14 base plates or screw jacks, and 7 mudsills. The top platform sits at 25.33 ft. At 20 ft the scaffold is exactly 4 times its 5 ft base width, so no wall ties are needed yet; any higher and ties start. The face area is 800 ft².
How to use the scaffold calculator
Choose feet or meters and the scaffold type: a frame scaffold with 5 ft wide frames, 7 ft bays, and 6 ft 4 in lifts, or a system scaffold with 0.73 m wide bays 2.57 m long and 2 m lifts. Enter the wall length and the working height, which is the height of the top platform you need. Enter how many levels are fully planked as working platforms and how many planks or decks fill one bay. Press Calculate.
Reading the scaffold quantity calculator result
The counts are a takeoff for one straight run. For a building with several walls, run each elevation and add them, then subtract the shared frames at the corners. Order a few spare planks, pins, and braces. The tie estimate uses maximum spacings; the scaffold supplier, the design, cladding or sheeting on the scaffold, and local rules often require more ties. A competent person must inspect the scaffold before use.
When to use a scaffolding calculator
- Estimating scaffolding for painting, siding, or brickwork
- Planning a scaffold rental order by bays and lifts
- Pricing scaffolding cost by face area
- Checking how many scaffold frames and planks a job needs
- Comparing frame and system scaffold for the same wall
Common scaffold calculator mistakes
- Forgetting the end frames. There is always one more frame line than bays.
- Planking every lift. Only working levels need full planking.
- Skipping ties above 4:1. Tall narrow scaffolds tip over without them.
- No base support. Every leg needs a base plate and a mudsill on soft ground.
Tips for scaffolding planning
- Measure each elevation separately and add the results.
- Keep the working platform within 14 in of the wall or add a back guardrail.
- Have a competent person inspect the scaffold before each shift.
Scaffold planks and working platforms
Only the levels you work from need full planking, guardrails, and toe boards, but the platform must be fully decked across the frame width with no gaps over 1 in (25 mm). A 5 ft frame usually takes two or three 19 in steel decks or wood planks, while system scaffold bays take two or three steel decks. Moving one planked level up as the job rises saves material, so many jobs order planks for one or two levels only. To plan the coatings or cladding on the same wall, the paint calculator and the siding calculator use the same wall dimensions.
Scaffolding cost by face area
Many contractors and rental yards price scaffolding by the face area, length times height, per week or per month, plus erection and dismantling. The face area here is the wall length times the working height, the same figure the wall area calculator gives before openings are removed. Add returns at the ends and the area of any loading bays or stair towers, which carry their own charges.
Frame scaffold quantities for common walls
| Wall | Height | Bays | Lifts | Frames | Cross braces | Planks (1 level) | Base plates | Wall ties |
|---|---|---|---|---|---|---|---|---|
| 20 ft | 10 ft | 3 | 2 | 8 | 12 | 6 | 8 | 0 |
| 40 ft | 20 ft | 6 | 4 | 28 | 48 | 12 | 14 | 0 |
| 60 ft | 30 ft | 9 | 5 | 50 | 90 | 18 | 20 | 3 |
| 100 ft | 40 ft | 15 | 7 | 112 | 210 | 30 | 32 | 5 |
Scaffold ties: OSHA maximum spacing
| Scaffold width | First tie | Vertical spacing | Horizontal spacing |
|---|---|---|---|
| 3 ft or less | at 4 × base width | 20 ft | 30 ft |
| More than 3 ft | at 4 × base width | 26 ft | 30 ft |
Scaffolding Calculator FAQ
How do you calculate how much scaffolding you need?
Divide the wall length by the bay length and the height by the lift height, round both up, then count frames, braces, planks, and rails from the bays and lifts.
How many scaffold frames do I need for a 40 ft wall?
With 7 ft bays the wall needs 6 bays and 7 frame lines, so 7 frames per lift; for 4 lifts that is 28 frames.
When does a scaffold need wall ties?
Under OSHA, once the height exceeds 4 times the base width. Ties then repeat every 20 or 26 ft vertically and every 30 ft horizontally.
When are guardrails required on a scaffold?
OSHA requires guardrails on platforms more than 10 ft above the level below, with a top rail, a mid rail, and toe boards where objects could fall.