Green or Greenwash?
As the effects of climate change have become real and a grudging acceptance that we should probably do something about it has become more mainstream, more and more marketers have tried to incorporate environmental qualities into their branding, sometimes mis-leadingly. ‘Greenwashing’ is the term for this, and it’s as prevalent in the building industry as in any other. Sometimes it’s literally green – friendly forest green packaging, say, or the fad for decorating sky-scrapers with improbably large trees. Often it’s in the language used - ‘environmentally friendly’, ‘sustainable’, ‘eco’, ‘natural’, vague terms which can be misleading by suggesting that the product is good for the planet, however it’s used. How do we - as Architects, builders, clients - determine what really is an environmentally friendly product or building? The answer is usually ‘it depends’, but there are some factors which we can consider.
Doughnut economics gives us a comprehensive way of mapping our impact on the planet. It acknowledges that we need to use resources to ensure a reasonable standard of living and takes the minimum for this as the inner edge of the doughnut. The planetary boundaries – or the maximum we can use sustainably – is the outer edge of the doughnut. It’s then sliced into different categories for different considerations. Ozone layer depletion is a great success story, the poster child for what can happen when we acknowledge an issue and get together to fix it. The two we’re doing worst at are climate change and biodiversity loss.
Climate change is being addressed, in part, with the 2016 Paris agreement, and our government’s Greenhouse gas emission reductions targets. Reporting on embodied carbon is going to be required in New Zealand from 2025, meaning building designers will need to calculate the carbon or carbon-equivalent which is going into the construction of each building. Concrete, steel and aluminium are carbon-intensive materials, while designing in timber is (usually) a reliable way to reduce a building’s embodied carbon.
Operational carbon is the other important way in which building’s contribute to climate change, encompassing things like heating, cooling and maintenance over the building’s lifetime. With New Zealand’s tradition of lightly-insulated stick-framed houses, we’ve been setting ourselves up to consume a whole lot of energy (and therefore carbon) for heating and cooling. In response, NZ’s Greenstar & Homestar accreditation systems are weighted towards rewarding buildings which provide a comfortable internal environment with lower energy usage, with lesser weighting towards embodied carbon and other environmental factors. The 2023 H1 regulation update has increased the mandatory minimums for insulation in our buildings, meaning our new homes will require less energy to keep warm – or comfortably cool – contrary to certain politician’s understanding!
Thinking about the whole of life carbon impact of a building can also mean thinking about its end of life. This isn’t always included in calculations; the economics of demolition make it unsafe to assume that a building will be carefully dismantled and recycled bit by bit. When factored in, however, we start to see greater value given to worthwhile improvements such as specifying less-toxic timber treatments, or to bolted steel structures which can be easily dismantled.
Biodiversity loss is also critical, and sometimes materials which look good from a carbon perspective look less desirable from a biodiversity one. A lot of the cedar cladding we import, for example, comes from old-growth forests - taking it out can mean taking out the surrounding ecosystems. Although not perfect, FSC certification is an internationally recognized accreditation providing assurance that a minimum standard of forest management has been achieved.
So where do these often contradictory drivers leave us with our aspirations to build our dreams without destroying the world? Going back to doughnut economics, the first step is always to do less. Pay less attention to the m2 way of valuing buildings. Question the wants and needs in your brief and work with an Architect to create a building of which every inch will be loved and used.
Secondly, interrogate what sustainable means for your project. If you’re looking to invest in a civic building with a lifespan of hundreds of years, an adaptable design with robust, durable and low-maintenance materials will eventually pay back – both financially and from an environmental accounting perspective. For something you suspect might get bowled in twenty, consider something relocatable, dismantlable, or with as light a footprint as possible.
Thirdly, ask suppliers what their spiel really means. Do they have an EPD (Environmental Product Declaration) meaning that their product’s environmental credentials have been assessed and verified? Does their product require less carbon to produce than its competitors? Is it less toxic? Does it require less maintenance in the 50 year building life-cycle which we typically work to in NZ? And in the context of your project, are these things really green, or is it just greenwash?
https://www.treasury.govt.nz/sites/default/files/2023-03/doughnut-economics-in-practice.pdf
https://www.buddlefindlay.com/insights/building-carbon-efficiency-into-new-zealands-future/
https://www.building.govt.nz/getting-started/building-for-climate-change
https://nzgbc.org.nz/
