Attaching a tarpaulin to scaffolding for weather protection sounds straightforward, but it carries genuine structural and safety risks that are easy to underestimate. In New Zealand, scaffolding is regulated work under health and safety law, and adding a tarp can dramatically change the loads the structure must handle. Here's what you need to know before you reach for the cable ties.
Why Tarps and Scaffolding Are a Serious Combination
A tarpaulin acts like a sail. Even a moderate NZ wind — and we get plenty of those — can exert enormous force on a sheeted scaffold. This wind loading can cause the entire scaffold to overturn, pull away from the building, or collapse. The risk is not just to the scaffold itself but to anyone nearby, including neighbours, passers-by, and your own family.
WorkSafe NZ treats scaffolding as a high-risk structure under the Health and Safety at Work Act 2015. Any modification that changes the structural loading — including adding sheeting or tarps — must be considered carefully and, in many cases, assessed by a competent person.
What NZ Law and Standards Say
Scaffolding in New Zealand is governed by NZS 4576:1995 (Guidelines for Scaffolding Safety) and WorkSafe's guidance documents. Under these rules:
- Scaffolding over 5 metres in height must be erected, altered, or dismantled by a licensed scaffolder (a Certified Scaffolder or Advanced Scaffolder under the Scaffolding, Rigging and Rigging certificate scheme).
- Adding a tarp to a scaffold that is already erected can constitute an alteration to that scaffold.
- The scaffold designer or erector must confirm the structure can handle the additional wind load before sheeting is applied.
You can check licensing requirements and find information on restricted work at WorkSafe NZ.
When a Homeowner Might Safely Attach a Tarp
There are limited situations where a homeowner may be able to attach a small tarp themselves — but only when all of the following apply:
- The scaffold is low-level (generally under 5 metres, such as a basic tower scaffold on flat ground).
- The scaffold was erected by a licensed scaffolder who has confirmed in writing that sheeting is permitted and the structure is rated for wind loading.
- The tarp is small, well-ventilated, or mesh-type (solid tarps catch far more wind than shade cloth or scaffold mesh).
- It is attached securely using proper scaffold fittings or purpose-made tarp clips, not improvised ties that can slip or fail.
- You stay off the scaffold while attaching the tarp from a safe position, or use a separate safe means of access.
- Weather conditions are calm — never work at height in wind or rain.
If you hired scaffolding from a company, contact them first. Most scaffold hire companies have specific terms about modifications, and adding a tarp without their approval may void any liability cover.
The Real Risks to Understand
| Risk | What Can Happen |
|---|---|
| Wind loading | Scaffold overturns or pulls away from building |
| Inadequate ties | Tarp tears free, becomes a hazard or damages property |
| Working at height | Falls are a leading cause of serious injury in NZ |
| Unauthorised alteration | You may be liable if someone is injured |
| Consent issues | Some temporary structures require building consent |
Falls from height are one of the most common causes of serious injury and death on NZ worksites and around the home. WorkSafe NZ has clear guidance on working safely at height.
Choosing the Right Tarp or Sheeting
If a licensed scaffolder has approved sheeting, use the right product:
- Scaffold mesh or shade cloth — allows wind to pass through, greatly reducing load. This is the preferred option for most scaffold enclosures.
- Solid poly tarps — only suitable on very small, low-level frames with proper engineering sign-off. Always use UV-stabilised, reinforced tarps with eyelets rated for the application.
- Proprietary scaffold sheeting systems — some scaffolding suppliers offer purpose-built enclosure systems designed to work with specific scaffold types.
You can find tarps and fixings at Bunnings or Mitre 10, but buying the right product is only part of the equation — correct installation and structural approval matter just as much.
Building Consent Considerations
In most cases, a temporary tarp on scaffolding during construction or maintenance work does not require a separate building consent. However, if the scaffold itself required consent (for example, as part of a larger building project), any significant modification may need to be discussed with your local council. Schedule 1 of the Building Act lists exemptions, but always confirm with your council if you are unsure — rules can vary. See MBIE Building Performance for general guidance.
When to Call a Professional
You should always engage a licensed scaffolder if:
- The scaffold is over 5 metres high.
- You want to fully enclose the scaffold with solid sheeting.
- The scaffold is on an exposed or elevated site (coastal, hilltop, or open paddock).
- You are unsure whether the existing scaffold is rated for the additional load.
- The scaffold was erected without your involvement and you don't have documentation.
A qualified scaffolder can assess wind loading, add the correct bracing, and attach sheeting safely and legally. You can find licensed scaffolders in your area on tradedirectory.co.nz.
Safety Reminder
Never climb scaffolding in windy or wet conditions, and never work alone at height. If a tarp comes loose in a storm, do not attempt to retrieve it from the scaffold until conditions are safe and you have help.
