If your roof is leaking, weathered, or starting to fail, choosing the right roof coating can save you thousands of dollars compared to a full roof replacement. However, not all roof coatings are created equal, and choosing the wrong product can lead to costly failures, repeat repairs, and ongoing leaks.
This guide explains the different types of roof coatings available in New Zealand, how they perform over time, and what you should look for when selecting the best solution for your roof repair project.
Why Choosing the Right Roof Coating Matters
Roof coatings are designed to waterproof and protect existing roofs, extending their lifespan while reducing maintenance costs. A high-quality coating can restore many roofs for a fraction of the cost of replacement.
Unfortunately, the roofing industry is full of conflicting advice and marketing claims. Some coatings perform exceptionally well in New Zealand conditions, while others deteriorate quickly, especially on flat roofs exposed to ponding water and UV exposure.
The key is understanding the differences between coating technologies, warranty coverage, silicone content, and long-term durability.
Does New Zealand Have the Harshest UV in the World?
A common claim is that roofing products must be “made for New Zealand conditions” because New Zealand supposedly has the highest UV levels in the world. While New Zealand does experience high UV levels compared to many countries, this statement is often exaggerated.
According to retired NIWA atmospheric research physicist and UV expert Richard McKenzie, New Zealand’s UV levels are lower than many equatorial regions and also lower than major UV testing locations in the United States, such as Southern California and Florida. For more details, read his article here.
This is important because many premium silicone roof coatings manufactured for the US market have already undergone extensive long-term UV testing in climates harsher than New Zealand’s. Products with proven long-term performance in those regions are generally well suited to New Zealand conditions.
Main Types of Roof Coatings
There are several different roof coating technologies available. Each has advantages and limitations.
Silicone Roof Coatings
Silicone roof coatings are widely regarded as the premium option for flat and low-slope roofs because they offer:
- Excellent waterproofing performance
- Outstanding UV resistance
- Long service life
- Resistance to ponding water
- Minimal maintenance requirements
High-solids silicone coatings also tend to maintain flexibility over time, helping roofs resist cracking and weather damage.
Acrylic Roof Coatings
Acrylic coatings are often less expensive initially but may require:
- More frequent recoating
- Additional maintenance
- Multiple coats
- Better drainage conditions
They can struggle on roofs where water ponds for extended periods.
Elastomeric Roof Coatings
Elastomeric coatings provide flexibility and waterproofing performance, but not all products tolerate permanent moisture or standing water well. Product quality varies considerably between manufacturers.
Aluminium Roof Coatings
Aluminium coatings are reflective and can help reduce heat absorption, but they are generally less durable than modern silicone systems and are not suitable for every roof type.
Not All Silicone Roof Coatings Are Equal
Many products are marketed as “silicone roof coatings,” but silicone content can vary dramatically between brands.
Some coatings contain very high silicone solids, while others are heavily diluted with fillers and additives. Silicone percentage affects:
- Longevity
- UV resistance
- Waterproofing performance
- Coverage rates
- Flexibility
- Overall durability
When comparing products, it is important to look beyond branding and focus on technical specifications.
Roof Coating Comparison
Below is a simplified comparison of commonly discussed silicone roof coatings in the New Zealand market.
| Product | Warranty | Undercoat Required | Coats | Silicone Content |
| Eterna-Kote | Lifetime | Usually No | 1 | 97±3% |
| APOC | Lifetime | Usually No | 1 | 97±3% |
| Kemseal 80 | 10 Years | Yes | 2 | 38% |
| Silcoat | 5 Years | Yes | 2 | 70% |
| Enduris 3500 | Up to 20 Years | No | 1 | Less than 45% |
In many cases, higher-solids silicone coatings require fewer coats, offer better waterproofing, and provide longer-term protection.
Why Silicone Content Matters
Silicone content plays a major role in long-term roof performance.
Higher silicone content generally means:
- Better UV stability
- Greater resistance to ponding water
- Longer lifespan
- Reduced cracking and chalking
- Improved waterproofing
Lower-solids coatings may still perform adequately in some situations, but they often require additional coats and more ongoing maintenance.
What About APOC Roof Coatings?
APOC has recently become more widely available in New Zealand and is manufactured by the same American company behind Eterna-Kote.
The product is designed as a high-solids silicone roof coating with a lifetime warranty and is also available in sprayable formulations, which can be beneficial for large commercial roof projects.
Other Roof Coating Options in New Zealand
There are also many non-silicone roof coatings available in New Zealand. These vary considerably in quality, warranty terms, and expected lifespan.
Before choosing any coating system, it is important to review:
- Technical data sheets
- Real-world project history
- Warranty limitations
- Recoat requirements
- Resistance to ponding water
- Independent customer reviews
Questions to Ask Before Choosing a Roof Coating
Before purchasing any roof coating, ask:
- How long is the warranty?
- Does the warranty cover ponding water?
- Is an undercoat required?
- How many coats are needed?
- What is the silicone solids percentage?
- Has the product been independently tested?
- Is the product suitable for flat roofs?
- How often will recoating be required?
- Are there genuine long-term case studies available?
- Is the product certified for potable water contact if required?
Final Thoughts
A quality roof coating can dramatically extend the life of your roof and avoid the enormous cost of replacement. However, product selection matters.
The cheapest option upfront is not always the most cost-effective long term. Higher-quality silicone roof coatings often provide better waterproofing, longer lifespan, lower maintenance, and fewer future repair costs.
Before making a decision, compare product specifications carefully, read independent reviews, and ensure the coating system is suitable for your roof type and environmental conditions.
For more information about Premium Silicone Roof Coatings, visit our website eternakote.co.nz