No — ratchet straps should not be used to stabilise a leaning scaffold tower. They are not designed or rated for this purpose, and using them in place of proper bracing or ties puts you and anyone nearby at serious risk of a collapse. If your scaffold tower is leaning, stop work immediately and do not climb it until the problem is properly fixed.
Why Ratchet Straps Are Not Suitable
Ratchet straps (also called tie-down straps) are designed to secure loads on vehicles or trailers. They are made to work in tension along a single axis and are not engineered to handle the complex, multi-directional forces that act on a scaffold tower — especially one that is already out of plumb. Key problems include:
- No rated load capacity for scaffolding use: Ratchet straps carry a working load limit for cargo restraint, not structural stabilisation.
- Stretch and creep: Straps can elongate under sustained load, meaning what feels tight today may be dangerously slack tomorrow.
- UV and weather degradation: NZ's high UV environment accelerates webbing deterioration, reducing strength unpredictably.
- No compliance: Using ratchet straps as scaffold ties does not meet the requirements of the relevant NZ scaffolding standard or the Health and Safety at Work Act 2015.
- False confidence: A strap may appear to hold the tower while masking a more serious underlying problem — uneven ground, a damaged base plate, or missing internal bracing.
What Actually Causes a Scaffold Tower to Lean?
Before fixing the lean, you need to understand why it's happening. Common causes include:
- Uneven or soft ground under the base plates or castors
- Missing or incorrectly installed diagonal bracing
- Damaged or bent frame sections
- Castors not locked on a mobile tower
- Overloading on one side, shifting the centre of gravity
- Wind loading on sheeted or enclosed towers
Each of these requires a different fix — none of which is a ratchet strap.
Correct Methods for Stabilising a Scaffold Tower
Proper stabilisation depends on the type and height of the tower, but approved methods include:
Base and Ground Preparation
- Use base plates (not just castors) on firm, level ground
- Place timber sole boards under base plates on soft or uneven ground to spread the load
- Ensure the tower is plumb in both directions using a spirit level before loading
Diagonal Bracing
- All scaffold towers must have diagonal braces installed as per the manufacturer's instructions — typically in an X-pattern on each face
- Never remove bracing to make access easier
Ties and Anchors
- For towers over a certain height (check your manufacturer's guide and WorkSafe NZ guidance), the tower must be tied to the building structure using proprietary scaffold ties — not ratchet straps, rope, or wire
- Ties must be fixed to solid anchor points such as purpose-built wall anchors or other anchor points rated for the purpose
Outriggers / Stabilisers
- Mobile towers should have outrigger stabilisers fitted when working at height, as specified by the manufacturer
- The height-to-base ratio must stay within the manufacturer's limits (commonly 3:1 for outdoor use)
NZ Legal Requirements You Need to Know
Under the Health and Safety at Work Act 2015 and associated regulations, anyone who erects or uses a scaffold has a duty to ensure it is safe. WorkSafe NZ provides detailed guidance on scaffolding requirements, including when a licensed scaffolder must be involved.
In New Zealand, scaffolding over 5 metres in height must be erected, altered, or dismantled by — or under the direct supervision of — a licensed scaffolder (a Scaffolding Certificate of Competence holder). Even below 5 metres, you are still legally required to ensure the scaffold is erected safely and in accordance with the manufacturer's instructions and relevant standards.
The relevant NZ scaffolding standard sets out design, erection, and inspection requirements. You can find information on applicable NZ standards through Standards NZ or by checking with WorkSafe NZ.
What to Do If Your Tower Is Leaning Right Now
- Stop work and clear the area around the tower
- Do not attempt to climb it or load it further
- If the lean is minor and the tower is at low height, carefully lower it to the ground and inspect all components
- Check the ground, base plates, bracing, and all frame connections
- Re-erect following the manufacturer's instructions exactly
- If you are unsure of the cause, or the tower is over 5 metres, call a licensed scaffolder
When to Call a Professional
You should call a licensed scaffolder if:
- The tower is 5 metres or higher
- You cannot identify why the tower is leaning
- Any frame components appear bent, cracked, or damaged
- The tower needs to be tied to the building and you are unsure how
- You are working on a commercial site or the scaffold will be used by others
- You feel uncertain about any aspect of the erection or stability
A qualified scaffolder will assess the situation, identify the root cause, and erect or rectify the tower to a compliant standard. You can find licensed scaffolders in your area on tradedirectory.co.nz.
