Erecting scaffolding on a steep bank beside your home is technically possible, but it is significantly more complex and hazardous than setting up on flat ground. In New Zealand, there are strict health and safety obligations that apply, and in many situations the work must be designed or supervised by a competent professional. Before you hire equipment or start driving in base plates, here is what you need to know.
Why Steep Banks Make Scaffolding Risky
Flat, firm ground is the foundation of any safe scaffold. A steep bank introduces several compounding risks:
- Unstable or loose soil that can shift under load, causing a leg to sink or kick out
- Uneven base levels that make it difficult to plumb and level the scaffold correctly
- Increased overturning forces — the steeper the slope, the greater the lateral load on the structure
- Limited tie-off points if the bank is away from the building wall
- Water and erosion — NZ's wet climate can quickly soften a bank, especially in clay-heavy soils common in many regions
Even a small amount of movement at the base can cause a scaffold to lean, rack, or collapse — with potentially fatal consequences.
NZ Health and Safety Obligations
Under the Health and Safety at Work Act 2015 (HSWA), anyone who erects scaffolding has a duty to eliminate or minimise risks so far as is reasonably practicable. WorkSafe NZ publishes specific guidance on scaffolding, including requirements for working at height.
Key rules to understand:
- Scaffolding over 5 metres in height must be erected, altered, or dismantled by a certified scaffolder. Check current WorkSafe NZ guidance for the specific qualification requirements that apply.
- Even below 5 metres, the person erecting the scaffold must be competent — meaning they have the knowledge, skills, and experience to do so safely.
- A hazard assessment must be completed before work begins. On a steep bank, this assessment becomes critical and should consider soil type, slope angle, drainage, and proximity to the structure.
- A scaffold handover certificate should be provided before anyone uses the scaffold.
For a steep bank scenario, WorkSafe would expect a documented risk assessment and, in most cases, involvement of a qualified scaffolder.
What Type of Scaffolding Works on a Slope?
Standard modular tube-and-coupler or system scaffolding can be adapted for sloped ground, but it requires careful engineering:
- Adjustable base plates and screw jacks allow legs to be set at different heights to achieve a level working platform
- Sole boards (timber pads) spread the load and prevent legs sinking into soft ground — essential on a bank
- Additional bracing and ties are needed to counteract the increased lateral forces on sloped terrain
- Raking legs or outriggers may be required to stabilise the structure
- In some cases, a bespoke engineered scaffold design is the only safe option — particularly on very steep or unstable banks
If the bank is very steep (generally over 20–25 degrees), a standard hire scaffold may simply not be appropriate, and a scaffolding company may decline to supply equipment without an engineer's sign-off.
Do You Need a Building Consent?
Scaffolding itself is generally a temporary structure and does not typically require a building consent under Schedule 1 of the Building Act 2004. However, this depends on the specifics — for example, if the scaffold involves any permanent fixing to the building or ground. Always confirm with your local council before proceeding, as exemptions can vary and councils interpret Schedule 1 differently. You can find general guidance at MBIE Building Performance.
Can a Homeowner Do This Themselves?
As a homeowner, you are not legally prohibited from erecting a small scaffold on your own property for your own use — provided it is under 5 metres and you are genuinely competent to do so safely. However, on a steep bank, the honest answer for most homeowners is: this is not a DIY job.
Consider the following checklist before deciding:
| Factor | DIY Feasible? |
|---|---|
| Scaffold under 5 m high | Possibly, if competent |
| Flat or gently sloping ground | Possibly |
| Steep bank (over ~15°) | Not recommended |
| Loose, wet, or clay soil | Not recommended |
| No suitable tie-off to building | Not recommended |
| Scaffold over 5 m high | No — must use certified scaffolder |
If any of the "not recommended" factors apply, you should engage a licensed scaffolding professional.
Practical Tips If You Proceed
- Never use ladders as a substitute for proper scaffolding on a bank — this dramatically increases fall risk
- Inspect the scaffold before every use, especially after rain
- Ensure guardrails, mid-rails, and toe boards are fitted on all open sides
- Do not overload platforms — check the rated load of your hired equipment
- Keep the area beneath the scaffold clear
- Review WorkSafe NZ's working at height guidance before starting
When to Call a Professional
You should always engage a qualified, experienced scaffolder when:
- The scaffold will exceed 5 metres in height
- The bank is steep, unstable, wet, or eroding
- You are unsure how to level or brace the structure
- The work is near power lines (contact your lines company — this is a serious hazard)
- You are hiring workers to use the scaffold (commercial obligations apply)
- Your scaffold hire company recommends an engineer's assessment
A professional scaffolder will carry out a site assessment, design the scaffold for your specific conditions, and provide a handover certificate. This protects you legally and — most importantly — keeps everyone safe. You can find qualified local scaffolders on tradedirectory.co.nz.
