A surprising answer to a hot question: controlled burns often fail to slow a bushfire



Firefighters conduct property protection as a bushfire approaches homes at Woodford NSW, Friday, November 8, 2019. Calls for more controlled burning are common after a major bushfire.
DAN HIMBRECHTS/AAP

Trent Penman, University of Melbourne; Kate Parkins, University of Melbourne, and Sarah McColl-Gausden, University of Melbourne

As sure as night follows day, this week’s bushfires prompted inevitable debate about whether fire authorities should have carried out more hazard reduction burning, and whether opposition from conservationists prevented this.

There are two key points to remember when we consider these questions. First, the impact on human life and property – not the impact on the environment – is the number one concern in the minds of fire officials when deciding whether to conduct a controlled burn. Second, and perhaps more importantly, evidence shows increasing the frequency or area of controlled burns does not necessarily reduce the bushfire risk.

In fact, during extreme fire danger conditions, reduced fuel loads – such as those achieved through hazard reduction burning – do little to moderate bushfire behaviour.

Firefighters protecting homes near Woodford, NSW as a bushfire approaches.
AAP

Officals under heat to cut fuel loads

Hazard reduction burning, also known as prescribed or controlled burning, is primarily used to prevent the spread of bushfires by reducing the build-up of flammable fuel loads such as leaf litter, grasses and shrubs.

Authorities routinely come under pressure to reduce bushfire fuel loads – especially in the wake of a bushfire crisis like the one seen on the east coast in recent days.

Media and mining magnate Kerry Stokes this week called for more controlled burning, saying this was a more pressing concern than climate change in dealing with bushfires.

And Nationals MP Barnaby Joyce reportedly lashed out at the Greens and others for purportedly opposing controlled burning and land clearing, claiming “there is all this bureaucracy that stands in the way of people keeping their place safe”.

The hazards of hazard reduction

Nationals MP Barnaby Joyce this week said ‘bureaucracy’ was getting in the way of rural landowners conducting hazard reduction on their properties.
Lukas Coch/AAP

Bushfire hazard reduction is not as simple as dropping a match indiscriminately and standing back to watch the landscape burn. Fire agencies must assess the risks and manage the potential impacts. These assessments are made in the years and months prior to the burn, as well as on the day.

Fire authorities invest significant time preparing for a controlled burn program. They work with communities to develop a plan and a rigorous process guides how, where and when the burns will be undertaken.

Protecting human life and property from the effects of a burn is the first priority, and by far represents the greatest challenge. Other impacts are also assessed in the process. These include effects on the environment, Indigenous and European cultural assets and sporting events.




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Mr Morrison, I lost my home to bushfire. Your thoughts and prayers are not enough


Despite extensive planning, over the past decade prescribed burns have escaped containment lines and destroyed houses, such as at Margaret River in Western Australia in 2013 and Lancefield, Victoria in 2015. To prevent a repeat of this, policies require burns only proceed when the weather is suitable not just on the day, but for three to five days afterwards. This has meant many burns do not go ahead or are delayed for years.

Smoke from fires can increase mortality and hospitalisation rates, and so the effect on human health is playing an increasing role in whether to burn or not. Viticulture concerns have also delayed burns because smoke can also destroy grapes used in wine production.

Thick smoke blankets Sydney Harbour in May 2019 after hazard reduction burns.
AAP

Controlled burns may not slow bushfires

Even if we were to carry out more controlled burns, it does not necessarily follow that bushfire risk would be reduced.

Controlled burns do not remove all fuels from an area. And forests accumulate fuel at different rates – some return to their pre-burn fuel loads in as few as three years.




Read more:
12 simple ways you can reduce bushfire risk to older homes


Our research has shown controlled burning was likely to have reduced the area later burnt by bushfires in only four of 30 regions examined in New South Wales, Victoria, South Australia and the ACT.

Evidence from a range of studies demonstrates fuel loads can significantly modify fire behaviour under benign weather conditions. But reduced fuel loads do little for bushfire mitigation under extreme fire weather and in times of drought.

A burnt-out structure on a property devastated by bushfires at Coutts Crossing in Northern NSW, November 2019.
Jason O’Brien/AAP

Looking to the future

Evidence is mounting of increased bushfire frequency and extent in both Australia and the US – a situation predicted to worsen under climate change. Changing weather patterns mean opportunities for controlled burning will likely diminish further. Coupled with expanding populations in high fire-risk areas, Australia’s fire agencies – among the best in the world – have a challenging time ahead.




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In future, we must think beyond traditional approaches to fire management. Acknowledging the role of climate change in altering natural hazards and the impact they have on humans and the environment is the first step. Communities should also be at the centre of decisions, so they understand and act on the risks.The Conversation

Trent Penman, Associate professor, University of Melbourne; Kate Parkins, Bushfire Risk Analyst, University of Melbourne, and Sarah McColl-Gausden, PhD student, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

12 simple ways you can reduce bushfire risk to older homes



There are no guarantees in bushfires, but you can improve the odds your house survives a blaze.
Photo by Edward Doody, courtesy of Arkin Tilt Architects, Author provided

Douglas Brown, Western Sydney University

Seventy-five years of Australian research into how houses respond to bushfire has identified 21 main weak points in houses and the area immediately surrounding them.

In recent decades this knowledge has been used to inform new building construction. But older houses are generally not built to the same standard, unless they have been significantly renovated.

Older homes make up the majority of buildings in bushfire prone-areas. There are some simple things that can improve the performance of an older house in a bushfire. Here are 12 suggestions: six simple projects that could be done over a weekend or two, and six low-cost things you could do in a single afternoon.




Read more:
Where to take refuge in your home during a bushfire


Six weekend projects:

1. Remove some garden beds next to the house

This is particularly true for garden beds near timber-framed windows and doors. For timber and fibro homes, garden beds adjacent to the house should be avoided entirely. At the very least prune dense bushes close to timber-framed windows back hard.

2. Sand and repaint weathered timber door and window frames

Over time, paint peels and cracks appear in the exposed and weathered timber. During a bushfire, embers can lodge in these cracks and ignite.

3. Enclose the subfloor with a metal mesh

Flammable items are often stored underneath the house. If this area is not enclosed these items will catch, often due to ember attack, and pose a threat to every room in the house. The exposed underside of timber floors can be protected with a lightweight, non-combustible layer.




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Curious Kids: how do bushfires start?


4. Repair or replace weathered timber decking

Just as embers can land in cracks in door and window frames, the same can also happen to weathered timber decking. Most decks are right next to the house and if they go up fire easily spreads to the home.

5. Have a 1-2 metre non-flammable area immediately around your house

Think of it as an additional protective defence area. You could use gravel, paving tiles, bricks, concrete, or ground rock such as scoria.

6. Get a professional roof inspection

Roofs gradually weaken and require maintenance. A professional roof repairer can check that tiles are in place, repair damaged ridge tiles, and ensure that skylights, air vents, evaporative coolers, and solar panels are in good order and are free from gaps where embers could enter.

The product specifications for timber door and window frames, metal mesh, and decking materials can be found in the relevant Australian Standard and steel construction standard. Actual requirements for houses vary according to the bushfire attack level associated with a specific block of land.

Open sub floor spaces are vulnerable, especially if used to store flammable material.
Douglas Brown, Author provided

Six easy afternoon projects

1. Replace natural coil doormats with synthetic

While they appear harmless, natural organic doormats can cause a fire to grow if they ignite. Due to their density they burn for a long time, and can spread flames to timber door frames. A synthetic mat will only flare up for a short time.

2. Remove organic mulch from garden beds next to the house

Burning embers can easily ignite dried-out organic mulch, setting fire to surrounding plants. If garden beds are near the house, particularly timber door and window frames, the danger is increased. Either remove mulch in garden beds next to the house or – if the mulch is suitable – dig it in deeply.

3. Store firewood in an enclosed metal container

It is best to store wood well away from the house, but no one wants to walk metres in cold winters to get that wood. So some firewood is often stored close to the house on a burnable deck, and often it’s left there over summer. Putting it into a large metal container can remove that fire risk.

4. Remove flammable material from the front porch, roof cavity, decking and underfloor area

When embers enter the roof cavity and underneath the house, flames can rapidly spread to every room. It is vital to keep these areas clear of flammable materials.

5. Replace timber benches on timber decks with synthetic ones

A timber bench on a timber deck next to a timber house is an unnecessary risk, similar to having a wood pile on a timber deck.

6. Turn pressure relief valves on outside gas bottles away from the house

Both the 2003 Canberra and the 2016 Wye River bushfires showed the danger of having gas bottle valves facing the house. In both fires, houses were destroyed when either the gas plume flamed or gas bottles exploded.

While these projects will improve the bushfire protection of your home, they can’t guarantee your home will survive a bushfire, especially during catastrophic bushfire conditions. It is also crucial to upgrade your home insurance so you can meet the higher costs of new building standards, in the event you have to rebuild. And in all cases, act on warnings given by your state or territory fire authority.


The advice given in this article is general and may not suit every circumstance.The Conversation

Douglas Brown, Casual Academic, Western Sydney University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: why your backyard lawn doesn’t help reduce carbon dioxide in the atmosphere



While growing grass takes up carbon dioxide, it emits it again back into the atmosphere when it is mowed or eaten.
from http://www.shutterstock.com, CC BY-ND

Sebastian Leuzinger, Auckland University of Technology


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

I read somewhere that 1,000 square metres of grass absorbs the same amount of carbon dioxide that one person produces. I then think about my small 10ha property. Does that mean that I am covering 100 peoples’ CO₂ emissions every day? What about those large 1,000ha properties then? Do they absorb thousands of tonnes of carbon every year?

In New Zealand, your average carbon footprint will be around four tonnes of carbon, emitted per year (based on the carbon contained in 16.9 tonnes of carbon dioxide equivalent annual per-capita emissions). A 1,000-square-metre area of grass will take up around one tonne of carbon per year. So if you didn’t fly much, lived in a well insulated home, cycled to work etc, you might bring your overall footprint down to around one tonne of carbon per year, the equivalent of what a backyard lawn may take up per year. So far so good.

The big problem (causing tremendous confusion even among scientists) begins right here. In the above, we talk about fluxes, not pools. Using your bank account as an analogy, fluxes are transfers, pools are balances.




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With your own carbon emissions, regardless whether they are one or four tonnes per year, you pay into the atmosphere’s account every year. This means that there is more and more carbon in the atmosphere.

That carbon comes from fossil fuels – an entirely different “account”. Regardless of whether you have 1,000 or 100,000 square metres, this is what grass is doing in this analogy: it takes carbon from the atmosphere every year, but that carbon is going straight back to where it was taken from when you mow the lawn and the biomass is broken down and returned to the atmosphere. In other words, your carbon footprint is a flux that leads to a permanent change in a pool (the atmosphere). This is a bit like a weekly salary. You don’t have to pay it back. What your lawn is doing however, is making payments that are returned a few weeks or months later (when you mow the lawn, a cow eats the grass, or when natural turnover takes place).

The bottom line is that short-term fluxes (as large as they might be) don’t matter if they are reciprocated by an equivalent but opposite flux. If you want, let’s do the experiment. You pay $1,000 onto my account ever odd week, and I pay $1,000 onto yours every even week. None of us will care – as little as the atmosphere will worry about the carbon that your grass patch briefly locks away from it.

So your grass won’t lock away carbon dioxide from the atmosphere in the long run. Neither will any grassland in New Zealand.




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Climate explained: why plants don’t simply grow faster with more carbon dioxide in air


If you wait long enough, things can become a bit more complicated, namely if my payments back to you start to become a little less or a little more, causing dollars or carbon to accumulate on one account rather than the other. While this is the case in some ecosystems, such as a growing forest, New Zealand grassland is unlikely one of them. So your backyard isn’t helping, there is no way around reducing our greenhouse gas emissions.The Conversation

Sebastian Leuzinger, Associate Professor, Auckland University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.

To reduce fire risk and meet climate targets, over 300 scientists call for stronger land clearing laws



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Without significant tree cover, dry and dusty landscapes can result.
Don Driscoll, Author provided

Martine Maron, The University of Queensland; Andrea Griffin, University of Newcastle; April Reside, The University of Queensland; Bill Laurance, James Cook University; Don Driscoll, Deakin University; Euan Ritchie, Deakin University, and Steve Turton, CQUniversity Australia

Australia’s high rates of forest loss and weakening land clearing laws are increasing bushfire risk, and undermining our ability to meet national targets aimed at curbing climate change.

This dire situation is why we are among the more than 300 scientists and practitioners who have signed a declaration calling for governments to restore, or better strengthen regulations to protect native vegetation.




Read more:
Land clearing on the rise as legal ‘thinning’ proves far from clear-cut


Land clearing laws have been contentious in several states for years. New South Wales relaxed its land clearing controls in 2017, triggering concerns over irreversible environmental damage. Although it is too early to know the impact of those changes, a recent analysis found that land clearing has increased sharply in some areas since the laws changed.

The Queensland Labor government’s 2018 strengthening of land clearing laws came after years of systematic weakening of these protections. Yet the issue has remained politically divisive. While discussing a federal inquiry into the impact of these policies on farmers, federal agriculture minister David Littleproud suggested that the strenthening of regulations may have worsened Queensland’s December bushfires.

We argue such an assertion is at odds with scientific evidence. And, while the conservation issues associated with widespread land clearing are generally well understood by the public, the consequences for farmers and fire risks are much less so.

Tree loss can increase fire risk

During December’s heatwave in northern Queensland, some regions were at “catastrophic” bushfire risk for the first time since ratings began. Even normally wet rainforests, such as at Eungella National Park inland from Mackay, sustained burns in some areas during “unprecedented” fire conditions.

There is no evidence to support the suggestion that 2018’s land clearing law changes contributed to the fires. No changes were made to how vegetation can be managed to reduce fire risk. This is governed under separate laws, which remained unaltered.

In fact, shortly after the fires, Queensland’s land clearing figures were released. They showed that in the three years to June 2018, an area equivalent to roughly 570,000 Melbourne Cricket Grounds (1,138,000 hectares) of bushland was cleared, including 284,000 hectares of remnant (old-growth) ecosystems.

Tree clearing can worsen fire risk in several ways. It can affect the regional climate. In parts of eastern Australia, tree cover reductions are estimated to have increased summer surface temperatures by up to 2℃ and southwest Western Australia by 0.4–0.8℃, reduced rainfall in southeast Australia, and made droughts hotter and longer.

Removing forest vegetation depletes soil moisture. Large, intact areas of forest typically have cooler, wetter microclimates buffered from extreme temperatures. Over time, some forest types can even become fire-resistant, but smaller patches of trees are typically drier and more flammable.

Trees also form a natural windbreak that can slow the spread of bushfires. An analysis of the 2005 Wangary fire in South Australia found that fires spread most rapidly through paddocks, rather than through areas lined with native trees.

Trends from 1978 to 2017 in the annual (July to June) sum of the daily Forest Fire Danger Index, an indicator of the severity of fire weather conditions. Positive trends, shown in the yellow to red colours, indicate increasing length and intensity of the fire weather season. Areas where there are sparse data coverage, such as central parts of Western Australia, are faded.
CSIRO/Bureau of Meteorology/State of the Climate 2018

Finally, Australia’s increasing risk of bushfire and worsening drought are driven by global climate change, to which land clearing is a major contributor.

Farmers on the frontline of environmental risk

Extensive tree clearing also leads to problems for farmers, including rising salinity, reduced water quality, and soil erosion. Governments and rural communities spend significant money and labour redressing the aftermath of excessive clearing.

Sensible regulation of native vegetation removal does not restrict existing agriculture, but rather seeks to support sustainable production. Retained trees can help deal with many environmental risks that hamper agricultural productivity, including animal health, long-term pasture productivity, risks to the water cycle, pest control, and human well-being.

Rampant tree clearing is undoing climate policy too. Much of the federal government’s A$2.55 billion Emissions Reduction Fund has gone towards tree planting. But it would take almost this entire sum just to replace the trees cleared in Queensland since 2012.




Read more:
Stopping land clearing and replanting trees could help keep Australia cool in a warmer future


In 2019, Australians might reasonably expect that our relatively wealthy and well-educated country has moved beyond a frontier-style reliance on continued deforestation, and we would do well to better acknowledge and learn lessons from Indigenous Australians with respect to their land management practices.

Yet the periodic weakening of land clearing laws in many parts of Australia has accelerated the problem. The negative impacts on industry, society and wildlife are numerous and well established. They should not be ignored.The Conversation

Martine Maron, ARC Future Fellow and Associate Professor of Environmental Management, The University of Queensland; Andrea Griffin, Senior Lecturer, School of Psychology, University of Newcastle; April Reside, Researcher, Centre for Biodiversity and Conservation Science, The University of Queensland; Bill Laurance, Distinguished Research Professor and Australian Laureate, James Cook University; Don Driscoll, Professor in Terrestrial Ecology, Deakin University; Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University, and Steve Turton, Adjunct Professor of Environmental Geography, CQUniversity Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Protecting wetlands helps communities reduce damage from hurricanes and storms



File 20181009 72133 1o1hr7u.jpg?ixlib=rb 1.1
Protecting coastal wetlands, like this slough in Florida’s Everglades National Park, is a cost-effective way to reduce flooding and storm damage.
NPS/C. Rivas

Siddharth Narayan, University of California, Santa Cruz and Michael Beck, University of California, Santa Cruz

2017 was the worst year on record for hurricane damage in Texas, Florida and the Caribbean from Harvey, Irma and Maria. We had hoped for a reprieve this year, but less than a month after Hurricane Florence devastated communities across the Carolinas, Hurricane Michael has struck Florida.

Coastlines are being developed rapidly and intensely in the United States and worldwide. The population of central and south Florida, for example, has grown by 6 million since 1990. Many of these cities and towns face the brunt of damage from hurricanes. In addition, rapid coastal development is destroying natural ecosystems like marshes, mangroves, oyster reefs and coral reefs – resources that help protect us from catastrophes.

In a unique partnership funded by Lloyd’s of London, we worked with colleagues in academia, environmental organizations and the insurance industry to calculate the financial benefits that coastal wetlands provide by reducing storm surge damages from hurricanes. Our study, published in 2017, found that this function is enormously valuable to local communities. It offers new evidence that protecting natural ecosystems is an effective way to reduce risks from coastal storms and flooding.

Coastal wetlands and flood damage reduction: A collaboration between academia, conservation and the risk industry.

The economic value of flood protection from wetlands

Although there is broad understanding that wetlands can protect coastlines, researchers have not explicitly measured how and where these benefits translate into dollar values in terms of reduced risks to people and property. To answer this question, our group worked with experts who understand risk best: insurers and risk modelers.

Using the industry’s storm surge models, we compared the flooding and property damages that occurred with wetlands present during Hurricane Sandy to the damages that would have occurred if these wetlands were lost. First we compared the extent and severity of flooding during Sandy to the flooding that would have happened in a scenario where all coastal wetlands were lost. Then, using high-resolution data on assets in the flooded locations, we measured the property damages for both simulations. The difference in damages – with wetlands and without – gave us an estimate of damages avoided due to the presence of these ecosystems.

Our paper shows that during Hurricane Sandy in 2012, coastal wetlands prevented more than US$625 million in direct property damages by buffering coasts against its storm surge. Across 12 coastal states from Maine to North Carolina, wetlands and marshes reduced damages by an average of 11 percent.

These benefits varied widely by location at the local and state level. In Maryland, wetlands reduced damages by 30 percent. In highly urban areas like New York and New Jersey, they provided hundreds of millions of dollars in flood protection.

Wetland benefits for flood damage reduction during Sandy (redder areas benefited more from having wetlands).
Narayan et al., Nature Scientific Reports 7, 9463 (2017)., CC BY

Wetlands reduced damages in most locations, but not everywhere. In some parts of North Carolina and the Chesapeake Bay, wetlands redirected the surge in ways that protected properties directly behind them, but caused greater flooding to other properties, mainly in front of the marshes. Just as we would not build in front of a seawall or a levee, it is important to be aware of the impacts of building near wetlands.

Wetlands reduce flood losses from storms every year, not just during single catastrophic events. We examined the effects of marshes across 2,000 storms in Barnegat Bay, New Jersey. These marshes reduced flood losses annually by an average of 16 percent, and up to 70 percent in some locations.

Reductions in annual flood losses to properties that have a marsh in front (blue) versus properties that have lost the marshes in front (orange).
Narayan et al., Nature Scientific Reports 7, 9463 (2017)., CC BY

In related research, our team has also shown that coastal ecosystems can be highly cost-effective for risk reduction and adaptation along the U.S. Gulf Coast, particularly as part of a portfolio of green (natural) and gray (engineered) solutions.

Reducing risk through conservation

Our research shows that we can measure the reduction in flood risks that coastal ecosystems provide. This is a central concern for the risk and insurance industry and for coastal managers. We have shown that these risk reduction benefits are significant, and that there is a strong case for conserving and protecting our coastal ecosystems.

The next step is to use these benefits to create incentives for wetland conservation and restoration. Homeowners and municipalities could receive reductions on insurance premiums for managing wetlands. Post-storm spending should include more support for this natural infrastructure. And new financial tools such as resilience bonds, which provide incentives for investing in measures that reduce risk, could support wetland restoration efforts too.

The dense vegetation and shallow waters within wetlands can slow the advance of storm surge and dissipate wave energy.
USACE

Improving long-term resilience

Increasingly, communities are also beginning to consider ways to improve long-term resilience as they assess their recovery options.

There is often a strong desire to return to the status quo after a disaster. More often than not, this means rebuilding seawalls and concrete barriers. But these structures are expensive, will need constant upgrades as as sea levels rise, and can damage coastal ecosystems.

Even after suffering years of damage, Florida’s mangrove wetlands and coral reefs play crucial roles in protecting the state from hurricane surges and waves. And yet, over the last six decades urban development has eliminated half of Florida’s historic mangrove habitat. Losses are still occurring across the state from the Keys to Tampa Bay and Miami.

Protecting and nurturing these natural first lines of defense could help Florida homeowners reduce property damage during future storms. In the past two years our team has worked with the private sector and government agencies to help translate these risk reduction benefits into action for rebuilding natural defenses.

Across the United States, the Caribbean and Southeast Asia, coastal communities face a crucial question: Can they rebuild in ways that make them better prepared for the next storm, while also conserving the natural resources that make these locations so valuable? Our work shows that the answer is yes.

This is an updated version of an article originally published on Sept. 25, 2017.The Conversation

Siddharth Narayan, Postdoctoral Fellow, Coastal Flood Risk, University of California, Santa Cruz and Michael Beck, Research professor, University of California, Santa Cruz

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Five ways to reduce waste (and save money) on your home renovation



File 20181003 101579 1aaxhoc.jpg?ixlib=rb 1.1
Sensible design can dramatically reduce waste of a renovation.
Photo by Nolan Issac on Unsplash, CC BY-SA

Deepika Mathur, Charles Darwin University

On average, renovating a home generates far more waste than building a new one from scratch.

This waste goes straight to landfill, damaging the environment. It also hurts your budget: first you have to pay for demolition, then the new materials, and then disposal of leftover building products.

By keeping waste in mind from the start and following some simple guidelines, you can reduce the waste created by your home renovation.




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1. It starts with the design

Waste is often treated as inevitable, factored into a building budget with no serious attempt to reduce it.

By raising the issue early with your architect, designer or builder, they can make decisions at the design stage that reduce waste later. Often the designers and architects don’t see their decisions contributing to waste – or rather, they don’t really think about it.

During my research on reducing construction waste, I asked one architect what he thought happens to the waste generated. He laughed with a glint in his eyes and said, “I think it disappears into pixie dust!”

One simple early decision that dramatically reduces waste is designing with material sizes in mind. If you have a ceiling height that does not match the plasterboard sheet, you end up with a tiny little strip that has to be cut out of a full sheet. In the case of bricks, not matching the ceiling height is even more wasteful.

Obviously not all materials will work together at their standard sizes (and you need to fit your renovation to the existing house). But sensitive design can make intelligent trade-offs, reducing overall waste.

When I asked architects why they don’t design zero-waste buildings more often, they said clients don’t ask for it. Make it part of your brief, and ask the architect how they can save money by using the materials efficiently.

2. Get your builder involved early

If you’re using an architect for your renovation, it’s common to have very little collaboration between them and the builder. Any errors or issues are usually spotted after construction has begun, requiring expensive and wasteful rework.

Instead, ask your architect and builder to collaborate on a waste management plan. Such integrated approaches have worked well in Australia and the United States.

This means clients, engineers and builders are collaborating, rather than taking adversarial roles. For such contracts to work, it’s important to involve all parties early in the project, and to encourage cooperation.

The briefing stage is an opportunity for architects, quantity surveyors and builders to work together to identify a waste minimisation target.

3. Whatever you do, don’t change your mind

One the biggest contributions to waste on sites is late design changes. Client-led design changes are identified in all literature as having far-reaching implications on waste.

These are mostly due to owners changing their mind once something is built. Reworking any part of a building due to design changes can account for as much as 50% of the cost overrun, as well as causing delays and generating waste.

The early work with your design and construction team outlined in the first steps gives you the chance to make sure you’re committed to your original design. Skimping in the planning stage can end up costing you far more in the long run.

4. Deconstruction, not demolition

Ask your builder not to demolish the building, but to deconstruct it. Deconstruction means taking a building apart and recovering materials for recycling and reuse. This provides opportunities for sorting materials on site.

Salvaged materials can be resold to the community or reused in the renovations. It greatly reduces the tip fees which are usually higher for mixed waste (typical from demolition process) and lower for sorted waste.

Of course this takes more time and has an additional cost. Therefore you do have to balance the cost of deconstruction against the savings.

Denmark, which recycles 86% of its construction waste, has made it mandatory for all government buildings to undergo selective demolition and sorting of construction waste. A good place to start in Australia is your state environment department, which may have guidelines on what is involved.

5. Choose materials carefully

Good-quality materials last longer, reducing maintenance later. Choosing manufacturers that use minimal packaging also reduces waste (be careful here to check the difference between “minimal” and “inadequate” packaging, as the latter can mean your material breaks).

Reusing materials from your renovation may also be an option (you will need to discuss this with architect and builder at the beginning of the project). Finally, using materials with recycled content is a great option, and boosts our recycling industry.




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In March 2017 the Housing Industry Association released data suggesting the Australian residential building industry will increasingly become more dependent on renovation work rather than new construction,

If you’re renovating your home, making efficiency and low waste a priority helps cut costs and reduce landfill.The Conversation

Deepika Mathur, Researcher in sustainable architecture, Charles Darwin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Coldplay conundrum: how to reduce the risk of failure for environmental projects



File 20180709 122277 1hwc3zh.jpg?ixlib=rb 1.1
As part of its commitment under the Paris Agreement, New Zealand’s government has committed to planting one billion trees within a decade.
from http://www.shutterstock.com, CC BY-SA

David Hall, Auckland University of Technology

New Zealand’s government has committed to planting one billion trees as part of a transition to a low-emission economy, in line with its commitments under the Paris Agreement.

The One Billion Trees Programme promises to deliver combined benefits, not only by offsetting greenhouse gas emissions, but also reducing erosion on marginal land. However, unless funding is closely tied to successful outcomes, this public investment risks failing in its environmental and political ambitions.

We have developed a results-based bond financing scheme that would remove the risk from forest planting and could be applied to forest and landscape restoration initiatives elsewhere in the world.




Read more:
Green bonds are taking off – and could help save the planet


The Coldplay conundrum

Globally, we face a major financing gap to fund the infrastructure required to mitigate the causes of climate change and to adapt to the consequences. The scale of global investment isn’t equal to the scale of the challenge. The Global Commission on the Economy and Climate estimates that core infrastructure investment needs to nearly double to about $6 trillion annually up until 2030.

The barriers to investment are many, but one is simply the risk of failure. I call this “the Coldplay conundrum”, after the British soft-rock band’s attempt to offset the greenhouse gas emissions created by their second album, A Rush of Blood to the Head. Money was transferred to southern India for the planting of 10,000 mango trees, yet, some years later, much of it hadn’t made it to landowners and, as a result, few trees survived. Coldplay, for all their green ambitions, ended up with egg on their face.

Politicians face the same risk when they embark on projects to deliver environmental outcomes. Although voters expect governments to deliver various public goods, there is also an expectation that public money will be managed effectively, efficiently and responsibly in doing so. Failing on either front could attract the wrath of the electorate.

The New Zealand government faces just this conundrum over its plan to plant a billion trees over the coming decade. It already manages various grants schemes, such as the Afforestation Grant Scheme and Erosion Control Funding Programme. But upscaling these could produce poor results if funding isn’t closely tied to successful outcomes.

A better solution

Results-based financing helps to manage this political risk. The idea is that governments only hand over the money once the desired outcomes are successfully delivered. The New Zealand government might guarantee to pay for trees that are successfully established, thereby attracting private and social sector parties to do this work – and to do it well. This contrasts with more common funding models, such as grants or output-based contracts, which might lead to success, but might also go the way of Coldplay.

My collaborator, investment specialist Sam Lindsay, and I have designed the Native Forest Bond Scheme, a results-based financing structure that would take the risk out of forest planting for the government, to enable innovation over business-as-usual. It is specifically designed to address the challenge of establishing continuous native forest on erosion-prone marginal land.

This is one of New Zealand’s most pressing environmental challenges. About 11% of the country’s total land area is mildly to severely erosion-prone but currently in pasture. Extreme weather events – which are expected to increase as a consequence of climate change – can trigger mass erosion, with costly damage to public and private property. Pastoral land, or land where forest was recently cleared, is particularly vulnerable.

Recent events in the Tasman District and Tolaga Bay, where torrents of sediment and forestry debris were flushed out of vulnerable catchments onto neighbouring properties and waterways, are a hint of the adaptation challenges to come.

Establishing permanent forest on this land is a no-brainer. It would increase land resilience and create large carbon stocks to offset emissions from elsewhere in New Zealand’s economy. A succession of reports, most recently by Vivid Economics and the Productivity Commission, have all highlighted the essential role of afforestation in meeting New Zealand’s Paris Agreement commitments. But landowners need help, because they often lack the cash, time or expertise to establish forests successfully.

Riding the global trend

The Native Forest Bond Scheme brings together parties around this common cause. Government provides the guarantee to pay for successful forest outcomes that generate significant public value through erosion control, carbon sequestration, meaningful regional jobs and greater biodiversity. Investors provide upfront capital for forest planting by purchasing the bond.

If outcome targets are successfully met, then investors are rewarded with interest payments, but if the planting programme underperforms, then investors bear the risk of project failure. By reallocating risks and incentives, the scheme enables parties to do what otherwise might not have been done.

Globally, other organisations are turning to results-based financing to create greener landscapes. At the city level, DC Water successfully issued such a bond to establish green infrastructure in Washington D.C., purchased by Goldman Sachs and the Calvert Foundation. At the international level, The Nature Conservancy and Climate Bonds Initiative are exploring the feasibility of sustainable land bonds, where developing countries would issue bonds to raise capital for land use change, and developed countries would then offset the interest payments as long as these changes are successful.

The ConversationThe Native Forest Bond Scheme is a tool for more effective financing of environmental outcomes. By tying funding to results, it creates a more credible commitment to the expectations of the Paris Agreement and UN Sustainable Development Goals. Without rethinking public investment, noble ambitions may ring hollow.

David Hall, Senior Researcher in Politics, Auckland University of Technology

This article was originally published on The Conversation. Read the original article.