Closed-loop material systems; Green chemistry; Industrial ecology


Cradle to cradle can be defined as the design and production of products of all types in such a way that at the end of their life, they can be truly recycled (upcycled), imitating nature’s cycle with everything either recycled or returned to the earth, directly or indirectly through food, as a completely safe, nontoxic, and biodegradable nutrient. With cradle to cradle, all the components of a product feed another product, the earth or animal, or become fuel: products are composed of either materials that biodegrade and become food for biological cycles or of technical materials that stay in closed-loop technical cycles, continually circulating as valuable nutrients for industry. It could be argued that cradle to cradle is equivalent to true sustainability – through the biological or technical components used, all products become sustainable as nothing becomes waste which cannot be reused.

The term “cradle to cradle” is largely attributed to William McDonough; however, it may have originated over 25 years ago, coined by Walter Stahel from Switzerland.


The industrial revolution brought with it a change in the way man interacted with the environment. For many years, little regard was paid, if awareness even existed, to the consequences of the way toxic materials were put into the air, oceans, and earth on a continual basis. Typically, large amounts of waste are created, much of which is valuable yet put into holes in the ground through landfill schemes; other waste is burned releasing toxins into the atmosphere and losing forever the potentially reusable elements. The industrial revolution created a “cradle to grave” system where resources from the earth are extracted, made into products (e.g., some of which require thousands of different chemical components – over 4,000 in a domestic television) and after use are disposed of in landfill or incinerators.

A typical manufacturing organization is often likened to an open system with inputs, a conversion process, and outputs (Fig. 1).

Cradle to Cradle. Fig. 1
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The organization as an open system

Within an open system such as this, the outputs are the desirable elements which customers directly pay for; however, it is recognized that there are externalities which are undesirable. These elements, whether gaseous, liquid, or solid are the direct residue of the conversion process; some accounts report that more than 90% of materials extracted to make durable goods in the United States become waste almost immediately (Ayres and Neese 1989).

In more recent years, efforts have been made to reduce the impact of the externalities through more efficient processes – much of the effort being centered on the principle of the 3Rs – reduce, reuse, and recycle – which ranks the methods associated with mitigating environmental impact of production or use of a product. Applied to the production process, the reduce element relates to the eco-efficiency movement which was largely born from the 1992 Rio Earth Summit involving 30,000 people from around the world, including representatives from 167 countries. Eco-efficiency also involves the principle elements commonly referred to as the triple bottom line, economic, environmental and ethical concerns, often related to the 3Ps of profit, planet, and people.

Taking the principles of industry under the influence of the eco-efficiency movement rather than the basic elements arising from the industrial revolution, Braungart and McDonough state that a retrospective look at the results might show it to be the design of a system of industry that:

  • Releases fewer pounds of toxic waste into the air, soil, and water each year

  • Measures prosperity by less activity

  • Meets the stipulations of thousands of complex regulations which reduce, without eliminating, poisoning

  • Produces fewer materials which can be so dangerous that future generations are required to maintain constant vigilance

  • Results in less externalities, especially waste

  • Puts smaller quantities of valuable materials into landfill where they can never be retrieved

Essentially, they state that it makes the destructiveness of the production process developed through the industrial revolution a little less so.

Braungart and McDonough state that the goal of an eco-efficient system is zero: zero waste, zero emissions, and zero “ecological footprint,” based on the principle that human beings are regarded as “bad” and that zero is a good goal but question what it would mean to be 100% good. These areas relate to the externalities of the open system.

Before considering the alternative, there are additional areas of the “cradle to grave” industrial system which should be considered – those relating to the actual product produced – the “desirable” element of the open system. One major element, a criticism of modern commerce and marketing in particular, is that it creates homogenous societies in which there is a commonality of design in both products and architecture which has led to a one size fits all strategy. Braungart and McDonough state that “imposing universal design solutions on an infinite number of local conditions and customs is one manifestation of this principle and its underlying assumption, that nature should be overwhelmed.” A point they make, however, is that nature’s entire energy requirement comes from the sun. Humans extract and burn fossil fuels, incinerate waste, and use nuclear reactors to provide energy despite “thousands of times the amount of energy needed to fuel human activities hits the surface of the planet every day in the form of sunlight.”

In current production systems, products are designed to appeal to customers at an affordable price while meeting performance and life expectations and complying with legislation for the markets they are sold in and produced according to the regulations in place where manufactured. A problem identified with this type of product is that it not only meets these criteria but often includes elements which make the production more efficient, potentially in terms of the 3Rs. Buyers may not know that these additional elements are included, and if they did, they may not want them as they could potentially be harmful to the user and future generations through the emissions they create, especially when the current practice of using low-quality materials to produce low price goods is involved. In particular, products can include ingredients such as benzene which is banned for certain uses in some Western countries yet still allowed in low-cost manufacturing countries, meaning that it is imported as part of a whole product – affecting products today and landfill for the future.

Recycling is not without its disadvantages – many products lose vital characteristics or gain undesirable chemicals as a part of the recycling process – paper being a prime example. Paper can only be recycled a finite number of times, at present technology only allows for seven cycles, and uses chlorine for bleaching – it is only virgin paper which may be chlorine free. Plastic milk bottles are regularly recycled to produce fleece material for clothing; however, at the end of the life of the jacket, it is likely to be sent to landfill, only prolonging the time taken for the plastic to end up there rather than going directly from the bottle. The alternative, however, for a fleece jacket is to use virgin polyester which would also end up in landfill so overall less polyester, and therefore oil, is used. Clothing company Patagonia claims to save 42 gal of oil and prevent a half-ton of toxic air emissions for every 150 jackets made from postconsumer recycled (PCR) polyester rather than virgin polyester (Chouinard 2006). Ultimately, unless the initial material in a product is specifically designed to be recycled, it can often be no better to recycle, and sometimes worse, than it would be doing nothing.

Aluminum is a rare product which becomes more efficient with recycling and can fit well to a cradle to cradle system – in addition to being indefinitely recyclable, it takes only 5% of the energy and produces only 5% of the emissions to recycle aluminum compared with aluminum made from virgin ore. These benefits grow incrementally each time aluminum is recycled.

In overall terms, the value of nations and organizations is measured through gross national product (GNP) which only measures the sales rather than the cost of goods sold. This can lead to anomalies such as when a national catastrophe, for example, an earthquake, destroys resources yet causes GNP to increase because money is spent on labor and materials despite the loss of the natural resources affecting the long-term capability of the nation.

The difference between efficiency and effectiveness is always an important distinction, often determined as efficiency being doing things right while being effective means doing the right things. Eco-efficiency can be seen as doing things right – more efficiently, reducing, reusing, and recycling, but it does not always mean doing the right things. A basic tenant of cradle to cradle is doing the right things – being effective. Braungart and McDonough define their concept “eco-effectiveness means working on the right things – on the right products and services and systems – instead of making the wrong things less bad.”

Contrasting this with the GNP measurement currently used for countries and the turnover and profit measures for organization, effectiveness and doing the right things in organizations means creating genuine growth taking the full cost of production into account not just now but for generations to come.

An example of a natural cradle to cradle system highlighted by Braungart and McDonough is a community of ants. They cite Hoyt 1996 in stating that as part of the daily activity, ants:

  • Safely and effectively handle their own material waste and those of other species

  • Grow and harvest their own food while nurturing the ecosystems of which they are a part

  • Construct houses, farms, dumps, cemeteries, living quarters, and food storage facilities from materials that can be fully recycled

  • Create disinfectants and medicines that are healthy safe and biodegradable

  • Maintain soil health for the entire planet

Despite this parallel, cradle to cradle does not advocate returning to a pretechnological state. Instead, it works on the principle that it is possible to incorporate the best of technology and culture to reflect a new view where products are made to reflect the full ability which ants display to work with, and for, nature rather than against it.

Braungart and McDonough suggest a new design assignment to encompass the broad ideas of cradle to cradle. “Instead of fine tuning the existing destructive framework, why don’t people and industries set out to create the following:

  • buildings that, like trees, produce more energy than they consume and purify their own waste water

  • factories that produce effluents that are drinking water

  • products that, when their useful life is over, do not become useless waste but can be tossed onto the ground to decompose and become food for plants and animals and nutrients for soil; or, alternatively that can return to industrial cycles to supply high-quality raw materials for new products

  • billions, even trillions, of dollars’ worth of materials accrued for human and natural purposes each year

  • transportation that improves the quality of life while delivering goods and services

  • a world of abundance, not one of limits, pollution, and waste”

For millions of years, the natural cyclical, biological system using the Earth’s major nutrients of carbon, hydrogen, oxygen, and nitrogen has nourished a thriving planet with diverse abundance. The industrial revolution has changed much of that with the extraction of a multitude of constituents which are transformed and merged into materials which cannot be recycled by the Earth and therefore create problems of waste and a reduction of resources. With growth and success measured purely by output of products rather than the full cost and effect of inputs, this non-cycle could continue until the resources expire. However, the cradle to cradle principle requires humans to learn to imitate nature’s highly effective system of nutrient flow and metabolism, in which the very concept of waste which serves no ongoing purpose does not exist and will allow continual, sustainable growth.

For true sustainability within the cradle to cradle system, products are composed of materials that biodegrade and become food for biological cycles or of technical materials that stay in closed-loop technical cycles, in which they continually circulate as valuable materials for industry, and sometimes a combination of the two, provided they are designed to be separable at the end of the “life” of the product. The cradle to cradle process travels full circle starting off with the creation of products that are safe for both human and environmental health and ending with the easy recovery and reuse of the materials in the products (Nahikian 2007).

In the early 1990s, DesignTex, a division of Steelcase, set out, with the help of Braungart and McDonough, to conceive and create a compostable upholstery fabric, after rejecting proposals for materials using a combination of cotton and recycled soda bottles (PET) due to the potential harmful effects of particles from the PET materials eroding during use the PET would make the end of life fabric a waste – the PET would not go back to earth safely, and the cotton could not be separated to be used again. The eventual material chosen was a combination of wool and ramie. The production process for the new materials was such that the water which exited the factory (an externality in the open system previously described) was as clean as or cleaner than the water entering. As Braungart and McDonough say, “Not only did our new design process bypass the traditional responses to environmental problems (reduce, reuse, recycle), it also eliminated that the need for regulation, something that any sane businessperson will appreciate as extremely valuable.”

Steelcase have now worked with cradle to cradle concepts for nearly 20 years and find that as consumers become more educated on issues of sustainability and they enforce stricter environmental guidelines when purchasing products, so much so that nearly 85% of their client proposal requests have an environmental component (Nahikian 2007).

While the industrial revolution has led to a “one size fits all” approach, cradle to cradle needs to take a more local approach, recognizing that people and environments vary considerably – local materials, resources, energy requirements and availability, and abilities to reuse elements either biologically or technically can be very different in different regions.

A current world situation is that there are countries which do accept types of waste that others do not. This means that waste of some types is transported to countries where it can legally be disposed of, even though the issue meaning it is not allowed elsewhere still exists. Because sustainability should be regarded as local, national, and global, cradle to cradle recognizes that it is not viable to allow externalities of emissions, effluents, or waste to pollute locally; it is also wrong to ship them elsewhere just because there is less regulation. “Connecting to natural flows allows us to rethink everything under the sun: the very concept of power plants, of energy, habitation, and transportation” (Braungart and McDonough 2008).

Buildings are an area where cradle to cradle can be, and is being, applied. Buildings utilize a large percentage of the energy, electricity, and raw materials used in the world while producing a significant amount of greenhouse gas emissions and waste (Nahikian 2007) Cradle to cradle can play a significant part in both the fabric of the building and the environmental footprint of commercial interiors. In the USA, there is a rating program from the Green Building Council – Leadership in Energy and Environmental Design (LEED) which promote sustainable building design and manufacturing processes. This is another area in which aluminum can play a role – recycled aluminum building products, along with other recycled materials, are routinely used with other recycled materials to earn points toward LEED ratings. One example of the use of aluminum in buildings is for roof shingles; they have many benefits over typical asphalt shingles including the ability to reflect 95% of sunlight to significantly reduce the requirement for air conditioning in the summer, in addition to being 100% recyclable at the end of their lives. Currently used asphalt shingles are dumped into landfill at the rate of 20 billion pounds per year (Sustainability Working Group, Aluminum Association 2009).

Taking this further, working with others at Oberline College, Braungart and McDonough “conceived the idea for a building and its site modeled so the way a tree works. We imagined ways that it could purify the air, create shade and habitat, enrich soil, and change with the seasons, eventually accruing more air than it needs to operate.” The building featured solar panels, wind protection from a grove of trees on the building’s North side, water storage for irrigation through a pond, and a separate pond for cleaning effluent through specially selected organisms and plants. The building did require upgrading of the initial solar-powered supply before it became a “net energy exporter” (Sacks 2008), but the fact it does this at all puts it ahead of most buildings.

One large project which has embraced cradle to cradle has been the revitalization of the Ford Rouge Centre – a US$2 billion price tag which included the redevelopment of a 600-acre brownfield site into a 2.3 million-square foot truck manufacturing plant. William McDonough worked with Ford primarily on landscaping, producing the world’s largest living roof (10.4 acres) which provides insulation and acts as a storm water retention area. The parking lot is porous to collect water which is used elsewhere in the plant, and there is a “fumes to fuel” system which recycles paint fumes high in volatile organic compounds (VOCs) into fuel to supply electricity to the paint shop (Business and the Environment 2006). Braungart and McDonough report that “the health of the site is measured not in terms of meeting minimum government-imposed standards, but with respect to things like the number of earthworms per cubic foot of the soil, the diversity of birds and insects on the land and of aquatic species in a nearby river and the attractiveness of the site to local residents. The work is governed by a compelling goal: creating a factory site where Ford employees’ own children could safely play.”

Other advantages accrue to organizations adopting cradle to cradle products and buildings. Eliminating harmful chemicals from business and manufacturing processes provides a cleaner, less toxic environment within which the employees work. This typically leads to reduced absenteeism due to sickness – green buildings being reported to reduce absenteeism by 15%, increasing overall employee productivity (Nahikian 2007).

As durable objects buildings can be designed to be adaptable for different uses in the future – changing from commercial use to domestic and back again as demands and needs change.

Products can be designed with future use in mind, when the Ford Motor company was manufacturing the Model T Henry Ford specified the size of the packing crates used for shipping components from suppliers. This was done so the crates could be dismantled and the wood they were made from could then be utilized, without further modification, for the floorboards of the car (Womack and Jones 2008). In a similar way, Maille, the French mustard producer, packages mustard in pots which can be used as drinking glasses once the mustard is finished – a design with future upcycling included.

The Sustainable Packaging Coalition, which includes 190 companies – Procter & Gamble, Kraft, and Starbucks, among them – is working to develop environmentally sound packaging practices (Sacks 2008). The coalition may help overcome the issues such as the one in China where Styrofoam packaging represents such a disposal problem that people often refer to it as “white pollution” (Braungart and McDonough 2008).

Braungart and McDonough state that while “It has famously been said that form follows function, the possibilities are greater when form follows evolution” – using soap as an example they point out that manufacturers could reconceive soap as a service based product, designing washing machines to recover detergent and use it again and again based on the fact that only 5% of a standard measure of detergent is consumed in the laundry cycle.

As the eco-effectiveness principles of cradle to cradle should celebrate commerce, Braungart and McDonough have created a visualization tool which allows a proposed design’s relationship to a multiplicity of factors to be creatively examined (Fig. 2).

Cradle to Cradle. Fig. 2
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Triple top line design factors

This tool allows the questions from people with different priorities to be addressed, while balancing them with other areas required for cradle to cradle ethos. Balancing the money (economy) with fairness toward others (equity) and the impact in relation to nature’s laws (ecology).

The phrase “triple bottom line” is often used in relation to sustainability, although often with economic factors taking precedence with organizations giving secondary consideration to how to maintain the profit while aiding the environment and ethical considerations. Using the above tool allows consideration of a “triple top line” moving from the conventional design criteria of cost, aesthetics, and performance which can be seen with the questions:

  • Can we profit from it?

  • Will the customer find it attractive?

  • Will it work?

The tool allows the factors to be incorporated in the initial design stages, gaining greater advantages than can be achieved by starting from a purely economic perspective.

Timberland is an organization which has introduced a product which closes the loop in many areas in terms of the biological and technical nutrients used for manufacture. The Earthkeepers 2.0 Boot brings Timberland closer to a closed-loop system. The boots are manufactured with:

  • Leather from a tannery-rated Silver for its improved water, energy, and waste management practices

  • 100% recycled PET lining made from recycled plastic bottles

  • 100% organic cotton laces

  • Durable Green Rubber™ lug outsole made from 42% recycled rubber

To close the loop, at the end of the life of the boot, customers return them to Timberland stores from where the company disassembles the main part of the boot, refurbishes the leather parts, recycles the PET lining, and recycles the soles into new Green Rubber (Schwartz 2009 and 2011).

Key Issues

A key issue for cradle to cradle as terminology is that it is potentially “owned” by William McDonough through trademarking. Certification to cradle to cradle standard is through McDonough Braungart Design Chemistry (MBDC) which to date has certified only a relatively small number of products.

Fundamentally, however, cradle to cradle can be seen as needing a backward step – not technologically as already discussed but in design terms. Stepping backward is required to consider all of the component parts and their material makeup, along with the process through which those components have been made. This is not a job which can be undertaken lightly or quickly – when Patagonia changed to organic cotton from conventionally grown cotton, it required a two-year process and a reduction in the cotton product line from ninety one styles down to sixty six (Chouinard 2006).

The issue is something which has to be addressed at the highest strategic level in an organization, but experience from those who have adopted the principles is that it does bring benefits economically to the organization, in addition to all the wider social benefits accrued.

Future Directions

In the book Cradle to Cradle, Braungart and McDonough outline the key steps organization can take to reach implementation of cradle to cradle:

Step 1: Get “Free of” Known Culprits

Eliminating the products and processes known to be harmful and ensuring that they are not just free of these but also that any replacements used do not cause harm.

Step 2: Follow Informed Personal Preferences

There are many areas in which there is no clear “right thing” to do, an example being the use of paper where recycled paper has obvious benefits over virgin pulp in some ways but introduces undesirable chlorine which is absent in virgin pulp, chlorine-free paper. With choices such as this (much as the frying pan and the fire), using personal preferences, particularly those know to include products which can have positive or favorable benefits is the best way to proceed.

A study was performed by Michael Braungart for Wella Industries, an international hair-care and cosmetic-products manufacturer that was trying to determine how people might be encouraged – through marketing and packaging – to choose environmentally friendly packaging for body lotions. A small but significant number of customers chose to buy the product in a highly unattractive “eco” package when it was placed next to the identical product in its regular packing on shelves, yet the numbers choosing the “eco” packaging when it was placed next to an over-the-top “luxury” package for the identical product skyrocketed (Braungart and McDonough 2008).

Step 3: Create a “Passive Positive” List

All the possible component parts of a product are considered in terms of their potential effects at three stage: in manufacture, during use and end of product life to establish alternatives which are positive as opposed to harmful. Negative elements are omitted, substituted by positive products without fundamentally changing the product, its design, or method of use.

Step 4: Activate the Positive List

The actual product is redesigned to include only good elements, considering how it can be made from biological and technical nutrients which can be returned to the Earth or reused at the end of the product life. It is suggested that with activation of a positive list, an organization might be encoding information about all the ingredients in the materials themselves, in a kind of “upcycling passport” that can be read by scanners and used productively by future generations.

Step 5: Reinvent

Moving forward, new systems are invented which look for different solutions to problems existing products meet – is a car the correct form of transport or can a different “product” be conceived to solve transportation needs and, in doing so, can it be more beneficial to the world and create real growth, for example.

This step, the final one in transformation to an eco-effective vision (and those preceding it), does not happen all at once. To put in place, it will require trial and error – trial and errors which will involve time, money, effort, and creativity to be spent in many directions.

As a final point, Braungart and McDonough state “It is important, however, that signals of intention be founded on healthy principles, so that a company is sending signals not only about the transformation of physical materials but also about the transformation of values.”

Cradle to cradle principles can be used to create truly sustainable products and services, recycling biological nutrients to the Earth and reusing technical nutrients in industrial processes sustainably.


Climate Change


Ecological Footprint

Industrial Ecology


Sustainable Consumption