We are often asked if particular scaffold arrangements ‘need’ to be designed. The HSE have compiled a list of scaffold arrangements they would expect to see a design for which can be found at the following link:


Confusion arises from the existence of TG20 guidance documents and historical practice within the industry.  ‘TG20:08 A guide to good practice for Scaffolding with Tubes & Fittings’ is a document derived from ‘BS EN 12811 Temporary Works equipment – Scaffolds’ – the British Standard for the design and erection of scaffolds.  TG20:08 attempts to interpret the requirements of BS and provides guidance notes for good practice in the design and erection of scaffolds.  In addition to this, it reproduces a number of design tables from which the intention is certain configurations of scaffold, if meeting the configuration arrangement, do not require any further design.  Unfortunately this has added to the confusion.

TG20:08 is very specific and prescriptive in the requirements of scaffolds which can be erected without further design such as where they are, the wind load on them, a maximum of 2m bays, a maximum of 2m lifts and whether they are netted or sheeted etc.  Although your configuration may meet all the criteria, our guidance is – What does your Customer want?

You can argue the configuration does not require a design as it is TG20 compliant but if they want a design then you’ll have to do one anyway!  Besides, there aren’t many large Contractors who would allow scaffolds to be erected on CDM sites without one, as they are often used for their own H&S and TWC management and they often need them to co-ordinate all trades who will be using the scaffold.

Scaffold structures that need to be designed

  1. Dead Shores
  2. Flying shores
  3. Raking shores
  4. Cantilevered scaffolds
  5. Truss-out Scaffolds
  6. Access Birdcages
  7. Façade retention
  8. Access scaffolds with more than the 2 working lifts allowed with TG20 ‘Basic Scaffolds’
  9. Buttressed free-standing scaffolds
  10. Temporary roofs and temporary buildings
  11. Support scaffolds
  12. Loading Bays founded on the ground
  13. Mobile and static towers outside base/height limitations
  14. Free standing scaffolds outside base/height Limitations
  15. Temporary ramps and elevated roadways
  16. Staircases and fire escapes
  17. Spectator Terraces and Seating Stands
  18. Bridge scaffolds
  19. Towers requiring guys or ground anchors
  20. Offshore scaffolds outside Offshore Contractors Association (OCA) handbook
  21. Pedestrian footbridges or walkways
  22. Slung and Suspended scaffolds
  23. Protection fans, Nets and Pavement Frames
  24. Marine scaffolds
  25. Boiler scaffolds
  26. Power line crossings
  27. Lifting gantries and towers
  28. Steeple scaffolds
  29. System scaffolds outside users guide parameters
  30. Sign board supports
  31. Sealing end structures
  32. Temporary Storage on Site
  33. Masts, Lighting Towers and Transmission Towers
  34. Advertising hoardings/banners
  35. Any scaffold structure subject to:
    • Vibration
    • High Loading
    • Long term duration
    • High risk areas
    • Loading from passenger/goods hoists

List extracted from the HSE website

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