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.
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.
The return of the breeze block
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.
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Stinging trees grow in rainforests throughout Queensland and northern NSW. The most commonly known (and most painful) species is Dendrocnide moroides (Family Urticaceae), first named “gympie bush” by gold miners near the town of Gympie in the 1860s.
My first sting was from a different species Dendrocnide photinophylla (the shiny-leaf stinging tree). It was like being stung by 30 wasps at once but not as painful as being stung by D. moroides, which I once described as the worst kind of pain you can imagine – like being burnt with hot acid and electrocuted at the same time.
I agreed to study stinging trees even after being badly stung. The puzzle was – what was eating the stinging tree? Stinging trees often have huge holes but no-one knew what was eating them. What could possibly eat the leaves that were so painful to touch? (Read to the end to discover the answer).
Stinging trees grow in light-filled gaps in the rainforest understorey and come in many different shapes, sizes and species (seven in Australia).
I studied two species for my PhD, Dendrocnide moroides and Dendrocnide cordifolia which is often mistaken for Dendrocnide moroides. Both species are shrubs that grow to three metres with heart-shaped, serrated-edged, dark-green leaves that can grow from the size of a thumbnail to over 50 cm wide.
The sting is caused by stinging hairs that contain toxin and densely cover the leaves, stems and fruit. The thick covering of the hairs makes the leaves look as though they are covered with soft, downy, fur and may give the impression they are inviting to touch.
The fruit of D. moroides is similar to a bright red-dark purple raspberry with long stems, while the fruit of D. cordifolia is always green with short stems that give the fruit a clumped appearance.
What it’s like to be stung
Even the slightest touch of a D. moroides leaf can cause excruciating pain. An intense stinging, burning pain is felt immediately, then intensifies, reaching a peak after 20 – 30 minutes.
The hairs can remain in the skin for up to six months, with stings recurring if the skin is pressed hard or washed with hot or cold water.
Not only do you feel pain from where you are stung, if it is a really bad sting, within about 20 minutes your lymph nodes under your arms swell and throb painfully and feel like they are being slammed between two blocks of wood.
The intense throbbing pain from both the sting and from your lymph nodes can last anywhere from 1-4 hours, depending upon what species you touched, the amount of skin that was stung, and how hard you came into contact with the plant.
How it works
The stinging hair structure is complex and consists of a tip, shaft and bulb composed of silica, calcium carbonate and calcium phosphate.
The tip of the hair is a small bulb that breaks off on contact, then the hair penetrates the skin injecting toxin. The structure and function of Dendrocnide stinging hairs is similar across five plant families and is described as similar to a hypodermic needle.
The composition of the toxin is also complex and still not well understood, including exactly what components actually cause the stinging sensation.
The toxin is stable and heat resistant and retains its pain-producing properties for decades. Dried botanical specimens collected over 100 years ago, can still sting you.
My worst sting was from a dead, dried-up leaf on the forest floor. I dropped my glove and then drove my finger through the leaf when I went to pick it up. As I was alone at the time, I had to drive to the hospital with one hand.
During my research in the late 80s-early 90s, I heard dozens of stories about people getting badly stung including a letter from an ex-serviceman, Cyril Bromley, who said he was stung after falling into a stinging tree while crossing a creek near the Barron River (North Queensland) in 1941. He said the pain was so bad they had to tie him to his hospital bed for three weeks. He also recounted how an officer had shot himself because he could not stand the pain.
The less well-known and very disturbing thing about stinging trees is they cause intense sneezing, nose bleeds, and possibly major respiratory damage, if you stay close to them for more than about 20 minutes without protection.
The reaction starts with your nose tingling, then dripping continuously. After a short period, you start to sneeze – not just mild sneezing but intense, harsh and continuous bouts of sneezing.
This happened to me and my field assistants when in close proximity to the plant, either in the rainforest or in the laboratory. Wearing particle face masks helps but they need to be regularly replaced. I believe that this reaction is caused by breathing in the hairs that become air-borne but I have never been able to substantiate this.
Researcher W.V. MacFarlane described his reaction in detail when working with hairs and leaves of D. moroides:
Mucous membranes are affected by dust or spray from the leaves… Initially they produced sneezing, but within three hours there was diffuse nasopharyngeal pain, and after 26 hours a sensation of an acute sore throat… aching sensations in the sinuses occurred… and a watery nasal discharge that persists for two days. The nasal mucous membranes then begin to slough together with blood, pus and inspissated (thickened) mucus… and discharge of sloughing tissue for 10 days.
The mystery solved
I found out what was eating them: a nocturnal leaf-eating chrysomelid beetle and many other leaf-chewing insects and sap-suckers.
Also, surprisingly, both species of stinging tree were voraciously eaten by the red-legged pademelons that occasionally stripped entire plants of their leaves overnight.
Meanwhile, if you are out and about in the rainforest, stay on the designated paths, and wear closed shoes and long pants.
It’s easy to write off Australia’s extreme weather as business as usual. We deal with floods, droughts, cyclones and other wild events every year. But as climate change raises global temperatures, are the droughts happening more often? Are the floods getting worse?
The October episode of Trust Me, I’m An Expert looks back through colonial evidence and prehistoric records, and forward to the Bureau of Meteorology’s Cyclone Weather Outlook for the year ahead.
The full episode will be released on October 8, but today you can catch a little of our interview with the Bureau of Meteorology’s Andrew Watkins. Keep an eye out for the full episode, where we ask: are we in uncharted territory, or is this life as usual on a changeable continent?
Trust Me, I’m an Expert: Risk
Trust Me I’m An Expert is a monthly podcast from The Conversation, where we bring you stories, ideas and insights from the world of academic research.
You can download previous episodes of Trust Me here. And please do check out other podcasts from The Conversation – including The Conversation US’ Heat and Light, about 1968 in the US, and The Anthill from The Conversation UK, as well as Media Files, a brand new podcast all about the media.
You can find all our podcasts over here.
- SensualMusic4You – “By Your Side” (Youtube)
Australia’s government has announced new planned waste recycling targets, as part of its response to the crisis prompted by China’s decision to crack down on recycling imports earlier this year.
That process is now in train. Following engagement with industry and government working groups, a proposed update to the policy is now open for public comment.
So how well does the proposed new policy incorporate circular economy principles? The short answer is, not well enough.
Explainer: what is the circular economy?
A circular economy is centred on keeping products, components and materials circulating in use for as long as possible, through long-lasting design, repair, reuse, re-manufacturing and recycling. The ultimate aim is to minimise the amount of resources consumed, and waste generated, by our economic activities.
The proposed principles, targets and strategies are a good start. They will help tackle a range of issues, including:
- dealing with China’s recycling imports crackdown by improving local capacity
- increasing the currently limited responsibility for products at end of life
- focusing on organic waste (such as food and textiles), one of the major obstacles to current recovery rates
- reducing litter and marine plastic debris
- harmonising the various disparate state policies.
Yet these proposals, while all crucial, represent only a moderate evolution from our current situation, rather than the revolution needed to truly embrace the circular economy.
The policy’s major focus is still on recycling and recovery, and while recycling is certainly a “circular” activity, the circular economy involves so much more than simply improving how we reclaim and reprocess unwanted materials.
A truly circular society aims to transform our whole system of production and consumption, with innovative approaches like “products as services” (through leasing or collaborative consumption) and designing for next life and new life (through repairability, modularity and disassembly).
Global changes, local opportunities
The proposed policy misses the opportunity to focus on innovation and create a step change in not only the resource recovery industry, but our whole economy and broader society.
The public arguably has more awareness of this issue than ever before, thanks to the continuing emergence of sustainability as a concept, combined with China’s shock to our recycling industry and the media focus afforded by campaigns such as the ABC’s War on Waste documentary series.
Public awareness and expectation is one thing, but to deliver on these goals the national waste policy must strengthen the explicit adoption of circular economy principles and significantly increase support to transition towards it.
This includes such things as:
- appointment of a Commissioner for Circular Economy
- explicit targets for reuse, repair, reassembly and remanufacture
- “Circular” procurement of goods and infrastructure
- support for innovation in business models for circular economy
- standards for imports, not just local production
- federal tax incentives, funding, and research and development to enable all of the above.
Australia has a unique opportunity to lay the building blocks for the type of economy and society we want. Let’s hope we can get it right.