Standard timber scaffold boards 225mm x 38mm are typically supplied in lengths 3.9m and weighing up to 24kg. All scaffold boards regardless of length could be vulnerable to normal wind uplift and the decision to secure scaffold boards should be determined by risk assessment, shorter boards may however require fixing to prevent movement. (Sites subject to extreme wind exposure may require additional typing down of scaffold boards).
TG20 recommends that scaffold boards of nominal thickness 38mm and less than 2.13m (7 feet) should be fixed down to prevent the boards from tipping. Scaffold boards supported by only 2 transoms should be fixed down at both ends of the board (Boards less than 1.6m in length), such short boards occur typically adjacent to ladder openings so must remain secure even under vibration and impact.
The overhang of any boards should not exceed four times the thickness of the board and should not be less than 50mm.
There are several products and methods that can be used to fix down scaffold boards to prevent movement such as proprietary board clips/clamps, rope lashing the list is not exhaustive. (Further guidance can be found in NASC publication TG12: Tying down of scaffold boards)
An Over-tube system can be used as a temporary measure on a scaffolder’s working platform or as a temporary measure in an emergency where rope or proprietary products are not available, the main disadvantage is that the over tube can form a tripping hazard. Consideration should be given to marking the tube with hazard warning tape.
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