As a general rule, if your roof pitch is steeper than 25 degrees (roughly a 5:12 pitch), it is considered too steep to work on safely without specialist equipment and training. Even on shallower roofs, falls from height are one of the leading causes of serious injury in New Zealand, so honest self-assessment is essential before you pick up a paintbrush.
Understanding Roof Pitch
Roof pitch describes how steeply your roof slopes. In New Zealand it is commonly expressed as degrees or as a ratio of rise to run (e.g. 25° ≈ 5.5:12). Here is a quick reference:
| Pitch (degrees) | Description | DIY suitability |
|---|---|---|
| 0–10° | Low / near-flat | Generally manageable with care |
| 10–25° | Moderate | Possible with correct equipment |
| 25–35° | Steep | High risk — professional recommended |
| 35°+ | Very steep | Do not attempt yourself |
To measure your pitch, you can use a digital angle finder (available at Bunnings or Mitre 10) placed directly on the roof surface, or use a standard spirit level and tape measure: hold the level horizontally, measure 300 mm along it, then measure the vertical drop to the roof — divide drop by 300 and multiply by 100 to get the percentage slope.
The Real Risk: Falls from Height
Falls from roofs are a leading cause of serious injury and death in New Zealand. WorkSafe NZ classifies roof work as a high-risk activity, and their guidelines apply to homeowners doing DIY work, not just tradespeople. Even a fall from a single-storey roof can be fatal.
Key risk factors beyond pitch include:
- Wet or damp surfaces — painted or moss-covered roofs become extremely slippery
- Roof material — Colorsteel and Zincalume metal roofing is more slippery than concrete or clay tiles
- Roof condition — brittle or cracked tiles can give way underfoot
- Working alone — if you fall, no one can call for help
- Ladder safety — an unsecured or incorrectly angled ladder is a hazard in itself
Minimum Safety Equipment for Lower-Pitched Roofs
If your roof is below 25° and you decide to proceed, you must have the right gear. Cutting corners on safety equipment is never worth it.
- Roof ladder or chicken ladder — hooks over the ridge and distributes your weight
- Non-slip footwear — rubber-soled boots with good ankle support
- Safety harness and lanyard — anchored to a certified roof anchor point
- Scaffold or edge protection — for eaves lower than 3 metres, edge protection is strongly advisable; above 3 metres it becomes critical
- A second person on the ground — never work on a roof alone
If you do not already own a harness and anchor system, hiring or buying this equipment can add significant cost to what might seem like a simple DIY job.
When the Roof Is Too Steep — No Exceptions
If your roof exceeds 25°, the honest answer is: do not attempt it yourself. At this pitch, without specialist training, the right scaffolding, and fall-arrest systems, the risk of a serious or fatal fall is simply too high. This is not a matter of confidence or fitness — it is physics.
Professional roof painters work with:
- Full scaffolding systems compliant with NZ standards
- Certified anchor points and fall-arrest harnesses
- Training in working at height under WorkSafe NZ guidelines
- Public liability and personal accident insurance
Roof Condition and Surface Checks
Before anyone goes on a roof — professional or otherwise — the surface should be assessed from the ground using binoculars or a drone. Look for:
- Cracked, broken, or loose tiles
- Rusted or lifted metal roofing sheets
- Soft or spongy areas that may indicate rotted sarking beneath
- Heavy moss or lichen growth (makes surfaces extremely slippery)
A roof in poor structural condition should be inspected by a qualified tradesperson before any painting work begins.
Choosing the Right Paint
Once safety is sorted, use a paint specifically formulated for your roof type. Resene and Dulux both offer dedicated roof coating systems for metal, concrete tile, and terracotta surfaces. Always follow the manufacturer's preparation and application instructions — proper cleaning and priming are just as important as the topcoat.
When to Call a Professional
Hire a qualified roof painter if:
- Your roof pitch is greater than 25°
- Your roof is two storeys or higher at the eaves
- The roof surface is in poor or unknown condition
- You do not have access to the correct safety equipment
- You are not confident working at height — trust your instincts
A professional roof painter will have the equipment, insurance, and experience to do the job safely and to a high standard. You can find qualified local roof painters on tradedirectory.co.nz.
Master Painters NZ member
Licensed Building Practitioner (LBP)
Roofing Association of NZ (RANZ)
