Scaffold Tie Calculator
Tie count from perimeter and height, with spacing limits checked.
Inputs
Result
Formula
| Vertical spacing ≤ 3 lifts (2 if sheeted) | |
| Horizontal spacing ≤ 3 bays | |
| Per row = ceil(perimeter ÷ horizontal spacing) | |
| Total = per row × ceil(height ÷ vertical spacing) |
200 m perimeter, 30 m high, 1.8 m lifts, 1.5 m bays, open scaffold: vertical ≤5.4 m and horizontal ≤4.5 m; 45 ties per row over 6 rows gives 270, each covering 22.2 m² (within the 40 m² limit). Fully sheeting it cuts vertical spacing to 3.6 m, needing 9 rows and 405 ties.
FAQ
Why are ties so critical?
They are the only members transferring horizontal load into the structure - resisting wind, overturning and overall instability. Nearly every scaffold collapse traces to missing ties, early removal or excessive spacing, especially during finishing when workers remove them to move materials: the sheeted face then acts like a sail. Ties are mandatory clauses, and removal needs approval plus substitute measures.
Why tighter spacing when sheeted?
Netting and panels turn the scaffold into a solid sail, greatly increasing the wind area. An open scaffold lets wind pass through the gaps; once sheeted, nearly all pressure lands on the frame and must be spread into the structure through more ties. That is also why netting is partly removed or extra guys added under wind warnings.
Can wire rope replace a tie?
Not on its own. Rope takes tension only, while a tie must resist both push and pull (wind pressure and suction). Codes require ties to carry tension and compression, normally a steel tube or section with couplers, or welded to cast-in plates. Flexible guys are supplementary only.
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Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.