15 minute read
Building for climate change
BUILDING FOR CLIMATE
CHANGE
The building and construction sector has a major role to play in helping New Zealand reach its goal of net zero carbon emissions by 2050—and a new Building for Climate Change programme has been set up to provide the pathway. NZ Plumber looks at some of the key issues, what’s being done and potential implications for the plumbing and gasfitting industry.
Buildings produce greenhouse gas emissions from the moment construction begins to the time they end their useful life. To help the building and construction sector meet New Zealand’s overall 2050 goal of net zero carbon emissions, the Ministry of Business, Innovation and Employment (MBIE) has set up the Building for Climate Change programme.
The first two programme frameworks were open for public feedback between August and October. The first looks at reducing carbon emissions across a building’s whole lifecycle—from production of construction materials through to end of life. The second looks at carbon emissions relating to a building’s operation, such as heating, cooling, lighting and ventilation.
A full summary of feedback received is due any day and MBIE says it received 360 responses, over half of them on behalf of organisations. Of these responses, 92% agreed that the building and construction sector needs to take action to reduce emissions, with 79% saying there are barriers that currently prevent them, or their business, from doing so.
1. Whole of life
Emissions associated with the construction materials and products across the lifecycle of a building are known as its ‘embodied carbon’.
This includes emissions from producing, transporting, constructing, replacing and disposing of materials and products.
DId You Know?
Together, building and construction are responsible for 39% of all carbon emissions in the world, according to the World Green Building Council. Of this, operational emissions (energy to heat, cool and light buildings) account for 28%. The remaining 11% comes from ‘upfront’ carbon associated with materials and construction processes throughout the whole building lifecycle. The construction sector in New Zealand is a dominant contributor to this country’s consumption-based greenhouse gas emissions (which takes into account greenhouse gas emissions from imported products and services), representing 16% of total emissions in 2018, according to Housing in Aotearoa 2020, published in December 2020 by Stats NZ.
The trend towards larger houses in NZ increases the carbon footprint of dwellings. According to the same study as above, some standalone houses currently being designed and built in NZ can exceed their allowable carbon budget by seven to ten times. Larger houses can use more emissions due to the amount of materials used, the type of construction, replacement and the number of people living in them. Water New Zealand’s newly relaunched Water Efficiency and Conservation Network (WE CAN) Special Interest Group is looking for members, including plumbers. The Association’s Special Interest Groups (SIGs) give an opportunity to share knowledge, discuss issues and distribute information. Find out more at waternz.org.nz/wecan or contact katrina.guy@waternz.org.nz
VICKY ROBERTSON Chief Executive, Ministry for the Environment
BRANZ Chief Executive Chelydra Percy is to head up the new environment workstream for the Construction Sector Accord (CSA)’s Construction Sector Transformation Plan.
“The workstream presents a significant opportunity to leverage great work already happening across industry and government and to identify the collective actions we can progress in this important and urgent area,” she said on her appointment in September.
Chelydra Percy will lead this workstream as part of the CSA’s Transformation Delivery Group. Other new members for this group are: Kevin Lavery, General Manager, Sector Consulting – Society of Local Government Managers John Sneyd, General Manager, Building System Performance – MBIE Peter Murray, General Manager Major Projects and Advisory – New Zealand Infrastructure Commission Duncan Kenderdine, Executive General Manager Strategy and Development –Downer NZ.
The Transformation Delivery Group is responsible for the design and delivery of the Transformation Plan’s workstreams and seeking wider support for sector change.
Find more about the Construction Sector Accord’s goals at constructionaccord.nz
Chelydra Percy, BRANZ Chief Executive, has been appointed to lead the environment workstream for the Construction Sector Transformation Plan.
The amount of embodied carbon in a new building depends on its size, along with the amount and type of materials and products used and their associated emissions.
Some factors to be considered when looking to reduce embodied carbon emissions are:
Using our existing building stock efficiently and effectively
Constructing buildings to be resilient and flexible to changing user needs, avoiding emissions from future rebuilds
Ensuring performance requirements are realistic to avoid over-engineered buildings
Reducing construction waste
Increasing longevity of buildings and construction materials and products
Increasing use of low-carbon construction materials and products.
What’s proposed?
MBIE is proposing to regulate the embodied carbon of buildings. This would initially be done through mandatory reporting for building projects. The data collected would be stored in a national repository. Once a sufficient level of sector understanding is in place, the first set of embodied carbon caps for buildings would come into force. These caps would tighten over time, to a given schedule.
2. Day-to-day operations
MBIE has set out three main objectives to increasing a building’s operational efficiency: 1. Reduce operational carbon emissions 2. Reduce water use; and 3. Improve the health and wellbeing of occupants by improving buildings’ indoor environmental qualities (IEQ).
It says these objectives can be met by:
Reducing the need for electricity, fossil fuels by: • Improving building thermal performance requirements so very little heating and cooling is needed. • Improving building services efficiency requirements so very little energy is used for lighting, hot water, ventilation and other systems.
Replacing fossil fuel use with electricity or other lower-carbon energy sources
Improving the efficiency requirements of potable water systems
Setting clear requirements for the
IEQ of buildings (eg, air temperature, humidity, ventilation, surface temperature, and daylight).
WHAT CAN I DO RIGHT NOW?
The Building for Climate Change programme has released the following tips to help the construction industry get ahead of the curve:
Increase your carbon literacy Develop your technical skills in these areas Start exploring and understanding the energy efficiency and carbon footprint of the buildings you help construct.
Alert clients to the MBIE Building for Climate Change Programme Start exploring and making use of energy and carbon modelling tools and techniques. Consider designing out construction waste Start separating and reducing construction waste—look for opportunities for construction waste to get reused or recycled.
Have an independent assessment of the energy efficiency and/or embodied carbon in a building system’s design Consider voluntary reporting/ disclosure of the energy efficiency and carbon footprint of your projects.
NZ CLIMATE ALREADY WARMING: NEW REPORT
A 2020 report from the Ministry of Environment and Stats NZ confirms our climate is already warming. Results from 30 monitored sites around NZ show increasing average winter temperatures in each site. Extreme rainfall, heatwave days and dry spell days are also starting to increase and frost days to decrease in some places.
“This report points to profound changes to New Zealand’s climate, and greater impacts on our wellbeing in the future, unless there is both local and global action to reduce greenhouse gas emissions,” said Ministry for the Environment Chief Executive Vicky Robertson and Government Statistician Mark Sowden on the release of the report in October.
“Covid reminded us that large-scale disruption to our lives can be abrupt, unwanted and unforeseen, and that some people, places and sectors are likely to be disproportionately affected,” says Vicky Robertson.
New Zealand’s net emissions have increased by 57% from 1990 to 2018.
Read Our Atmosphere and Climate 2020 at www.mfe.govt.nz/publications/
environmental-reporting/our-atmosphere-and-climate-2020
What’s proposed?
MBIE proposes to regulate operational efficiency through the following set of requirements at the building consenting stage:
An operational emissions cap per square metre per annum for buildings, which would include a: • thermal performance requirement • building services efficiency requirement • potable water use requirement • limit on the use of fossil fuels
A set of measurable requirements for indoor environmental quality.
The operational emissions cap and performance requirements would be reviewed and tightened at regular intervals to reach a final cap by 2035.
Operational emissions reporting, ongoing commissioning requirements and post occupancy evaluation for completed buildings is also being considered.
The framework will apply to new buildings, including housing, communal residential, communal nonresidential, commercial, and industrial buildings.
What about existing building stock?
Buildings that currently exist are predicted to make up 65% of New Zealand’s building stock in 2050 and a similar proportion of emissions. It is proposed that changes to existing buildings will be addressed in future work by the Building for Climate Change programme.
2021 Draft Advice for Consultation
Proposed ban on new household gas connections “short sighted”, says Master Plumbers
The first official draft advice report from the independent Climate Change Commission, released in February, proposes a ban on new residential gas connections by 2025 and the phasing out of existing gas in homes by 2050.
Master Plumbers says the proposal is short-sighted, given that work is underway in Australia and New Zealand to see how carbon-free green hydrogen can be incorporated with the current gas network and appliances.
CEO Greg Wallace says the fact that existing infrastructure could be used to move to hydrogen is very appealing, but its introduction is likely to be beyond the timeframe proposed in the report.
He noted that current residential gas use accounts for just 3% of New Zealand’s total gas use and the proposed changes would also have cost implications for both current and new homeowners, with very little benefit.
“Homeowners want instant, reliable hot water and like the space and energy savings of gas continuous flow systems, which mean they don’t have to store large amounts of water in cylinders.
“Surely the right order of doing this would be providing a renewable energy source that offers these same benefits, rather than saying you can’t use gas but we don’t really have an alternative that offers the same benefits,” he said.
The draft advice report is open for feedback until 14 March at https://haveyoursay.climatecommission.govt.nz
THE CITY’S BREAKING AND EVERYBODY’S SHAKING
This article on how climate change may affect the construction industry is adapted from an award-winning essay by Hesketh Henry solicitor Lydia Sharpe.
Climate change may be the biggest existential threat the human race has faced. While climate change will affect a wide range of entities, it will have a particular impact on the construction industry. This article analyses how climate change may affect the construction industry and considers how to avoid the worst of its potential impacts.
It is well-known that climate change will have significant, long-lasting effects on global weather patterns. Some of these effects may be irreversible. Scientists have predicted that the global average temperature will increase by 2.9 to 3.4°C by 2100, compared to the pre-industrial period. Summers are predicted to heat up by 3-4°C; regions which currently tend to be dry or arid will likely experience a higher risk of drought, while more humid regions will have a higher risk of heavy rain and floods.
Climate change also exacerbates the intensity of severe weather such as cyclones and hurricanes, largely because of the increase in global temperatures. Warmer temperatures mean more moisture in the air, which causes increased rainfall during hurricanes. Although the severity of individual storms cannot be directly linked to climate change, it is clear that, overall, global warming is affecting our weather.
In addition to its impact on the weather, climate change is causing a rise in global sea-levels, which will lead to an increase in floods. Globally, the consequences of sea-level rise are significant, and it is our neighbours in the Pacific who will feel the greatest effects. This may lead to thousands of displaced people seeking refuge as their low-lying islands become inundated.
Impacts on buildings
Climate change will also likely affect physical infrastructure. As heatwaves become more frequent and last longer, buildings which are not built to a standard that can adequately regulate indoor temperature may adversely affect occupants’ health. Heatwaves, like the one that caused Auckland’s drought earlier this year, can lead to soil shrinkage and subsidence, more rapid deterioration in concrete, and internal overheating of some buildings such as traditionally-constructed high-rise apartments.
Those who are particularly vulnerable to heat-related illness and death include the elderly and individuals with underlying health conditions. Buildings not built to cope with increasingly extreme weather conditions—whether increased heat or increased rainfall—may offer inadequate protection to vulnerable inhabitants.
Finally, where construction crews are expected to work in increasingly hot conditions, work may need to progress slower than was once normal to avoid workers experiencing heat stroke and dehydration. This may cause delays to the construction timetables and attendant increase in costs.
Likewise, more severe and frequent cyclones or hurricanes will affect construction work. Buildings hit by these severe, more frequent storms are likely to be more damaged and more often than by previous storms. This could lead to increased costs to repair and enhanced performance requirements to resist multiple severe storms. Further, the increased frequency of floods will have a deleterious effect on buildings constructed on low-lying ground.
To mitigate these effects, future buildings may need to be constructed to withstand different types of weather conditions than those for which they are currently constructed, such as higher wind strength, higher average temperatures and increased rainfall or floods. This will affect the types of materials and building methods used.
Implications for contracts and insurance
Climate change will also affect risk and liability under construction contracts and related insurance products. Bad weather, whether extreme winds, floods or rainfall, can cause delays to construction projects if the weather is such that it is unsafe to continue work and the project cannot be reprogrammed to mitigate.
Delays, particularly if they affect critical path items, can lead to increased expenses, particularly for contractors. To mitigate their loss and avoid the imposition of liquidated damages, contractors often submit claims for extensions of time. But, although weather is specified as a ground for an extension of time under a number of NZ contracts (such as NZS 3910, 3915 and 3916), it is not clear whether delays caused by weather exacerbated by climate change can be the subject of a claim for an extension of time.
It is unclear to what extent insurance providers in New Zealand are considering the likely effect of climate change. But it is accepted overseas that, by mid-century, climate change will be a major driver of increased risks and losses for the insurance industry. Analysts are currently trying to recalculate their insurance models to capture the effects of climate change. But current models use data derived from previous weather events to model future weather events: because climate change is having a continued and often unpredictable effect on previous weather norms, historical data does not accurately represent future weather.
As risks related to climate change become more certain, insurance companies may respond by increasing premiums on, for example, property and contract works insurance. Alternatively, they may exclude cover for certain risks exacerbated by climate change such as severe weather or floods, or decline cover altogether in regions particularly at risk. This may make it harder for home owners, developers and contractors to obtain and/or afford insurances. This in turn may impact developers’/home owners’ ability to obtain finance for construction/renovation; from the contractor’s perspective, increases in premiums may disproportionately affect smaller construction companies.
Looking to the future
Looking forward, climate change will likely require significant developments in the construction space. Although it is currently difficult to tell precisely what these developments will be, the following are some possibilities.
Consumers will almost certainly raise demands for more eco-friendly products. One example of this is concrete, the production method of which releases significant amounts of carbon dioxide into the atmosphere. Overseas, companies are seeing a gap in the market for less-carbonintensive options, including pozzolans and other natural concrete alternatives. These products are often inexpensive and environmentally friendly, and the production process for pozzolans avoids the release of greenhouse gases commonly emitted during cement production. In response to customer demand, a likely growing area for the construction industry lies in developing more eco-friendly building products and methods.
As new, environmentally-friendly building products and methods are developed, the regulatory and legal regime will also need to develop with them. It is likely that MBIE will, over time, make significant changes to the Building Code to address these new building products and methods. Although this might be done through the biannual Building Code update programme, it is likely that more extensive legislative reform will be needed. MBIE’s latest consultation programme, Building for Climate Change, is worth watching.
On a larger scale, it is imperative that governments continue to pursue sciencebased adaptation and mitigation efforts to tackle climate change more broadly, and this should include consultation with the construction industry as a key stakeholder.
Realistically, it is too early to forecast with any certainty what the long-term future might hold for the construction industry in dealing with the impacts of climate change. The construction industry will need to be highly responsive to events as they arise, but today we still have a chance to avert the worst effects of climate change. The industry should seize this as an opportunity for real innovation.
About the author: Lydia Sharpe is a Solicitor in the litigation team at Hesketh Henry. She has a BA/LLB(Hons) and Diploma of Languages from the University of Auckland. This article is adapted from her essay originally published by the New Zealand Society of Construction Law in respect of the Society’s Essay Prize.
