🌱 Greenwashing: When Warm, Dry, Eco, & Healthy Claims Fall Short

Spec homes—from major NZ residential builders operating under the bare minimum Code—are increasingly marketed as “warm, dry, energy-efficient, healthy” homes. But buyer beware: many of these claims are more sales spin than substance.

We recently came across some interesting adverts from New Zealand residential builders and suppliers making rather remarkable claims about being eco-friendly and energy efficiency. Let's look into this a little further.

Expose 1. Steel Framing


🏡 Why We Don’t Use Lightweight Steel Framing

At Arbol, we’re all about building healthy, high-performance homes for New Zealanders – homes that feel good to live in and do good for the planet. That’s why we don’t use lightweight steel framing.

It’s not just a preference – it’s a decision based on science, sustainability, and lived experience. Here's why steel doesn't cut it for us… and what we use instead.

❄️ 1. Cold Bridges: The Steel Achilles’ Heel

Steel is 400x more thermally conductive than timber. Even if your walls are well insulated, the steel studs act like straws – sucking warmth out in winter and letting heat in during summer.

The result? Cold spots, condensation, and higher energy bills. In contrast, NZSIP and Arbol Timber systems are continuous and airtight – like wrapping your home in a puffer jacket. No thermal gaps, no compromises.

🌱 2. Embodied Carbon: Steel’s Dirty Secret

Producing 1 tonne of steel emits nearly 1.85 tonnes of CO₂. That’s before transport or construction. In a time when every kilogram of carbon matters, this just doesn’t make sense.

Timber, on the other hand, stores carbon. And when we build with NZSIPs – which combine engineered timber with high-performance insulation – we dramatically lower the environmental impact of the entire structure.


🛠️ 3. Tricky to Work With

Steel requires specialist tools, corrosion prevention, and careful planning. And once your walls are up, retrofitting is a nightmare.

Timber is easy to modify, and NZSIP panels are pre-cut offsite with millimetre precision. Less faffing, fewer delays, less waste. Just smart, clean building.


🔇 4. Poor Acoustics: Tin Can Living?

Steel transmits sound more easily than timber. That means more internal noise, echo, and vibration – not ideal for a calm, comfortable home.

SIPs, with their solid, insulated cores, naturally dampen sound. You’ll notice it immediately – our homes feel solid, quiet, and serene.


🌏 5. Movement Issues: Flex Isn’t Always Friendly

In seismic zones like Aotearoa, materials need the right balance of strength and flexibility. Steel can flex under load, sometimes causing cracking or fixture issues.

NZSIPs, paired with engineered timber, create a strong, rigid shell that performs exceptionally well under seismic stress. Built for the long haul.


✅ What We Choose Instead: Timber & NZSIP

We build homes using natural timber framing or NZSIP panels – or both. Why?

  • Thermally superior – No cold bridges
  • Low embodied carbon – Better for the planet
  • Simpler to build and live with – Less hassle, more flexibility
  • Better acoustics – Peaceful living
  • Earthquake-ready – Structurally resilient

When combined with our design-led approach and focus on sustainability, the results speak for themselves.

Remember when you buy an Arbol you are entering into a complete eco-system

- Average 50% more insulation than H1 Building Code
- uPVC Window Joinery that is thermal recessed and sealed
- Filtered fresh air ventilation with heat recovery (MVHR)
- Lightbridge Glazing
- Reduced thermal bridging
- Ventilated roof and wall cavities
- Internal service cavities
- Airtightness levels of Passive House standard 0.65ACH or better
- Better material choices that last longer and reduced toxicity
- High quality finishing - we strive for perfection
- Reduced waste - reduce, reuse, recycle
- Faster build times

All for a home that is healthier, comfier, longer lasting, and costs less to run.

Learn more about The Arbol Difference here: https://arbol.co.nz/pages/the-arbol-difference

Want to experience the warmth, comfort, and performance of an Arbol home?
Let’s build a better kind of home – together.

Book an appointment through our contact page to get the journey started.