Food Waste Decomposition Systems

By: Cassandra Kliewer | Sustainable Associate
Josie Plaut | Associate Dirtector


Food Waste

In 2010, America wasted an estimated 34 million tons of food and only about 3% of that waste was diverted from landfills. Food
digesters, which turn food waste into compost and gray water, are especially well-suited for large commercial kitchens like those found in hospitals and university campuses. Instead of putting food waste into landfills, food digesters turn waste food, into new soil and reduce the burden on municipal waste water treatment facilities.  Two waste audit studies, conducted by The Institute for The Built Environment for Rocky Mountain National Park, show that between 16-30% of the park’s waste, by weight, is food waste.

Food Digesters

Food digesters can either work with or without water. Both systems use an additive to accelerate the process of decomposition. Normally, the decomposing process would take a month, but instead the additive processes the food in 24 hours. The water-based process produces compost and gray water, which is water that is similar to the waste water from sinks and showers.  In a building that is connected to a municipal waste water treatment facility, gray water is easily treatable by the municipal waste water systems.  Gray water can also be treated on site and used for things like landscape irrigation.  Conversely, the dry system is evaporation-based and food waste is mixed with a decomposing additive. Both systems provide easy and sustainable solutions to landfill waste.
Food digesting systems produce nutrient rich material that can be used as compost to fertilize soil for landscapes. Since the dry system can digest food within 24 hours, a rapid source of compost for landscaping is readily available. If the building does not need compost, the facility can reach out to the community and provide compost for landscaping purposes elsewhere. Another benefit of having a food
digester is that it reduces the amount (and cost) of waste that would normally go to a landfill. Since food waste is composted on site with a food digester, there is also a benefit to reduced transportation cost and emissions.  In addition to saving dollars and emissions, and perhaps most importantly, wasted food is kept in the nutrient cycle to rebuild soil and is kept out of landfills where it contributes to methane gas production.

The Future of Food Waste

Various government officials have noticed the impact of food waste and are taken measures against food waste.  Massachusetts has taken measures to ban food waste from big food wasters (schools, hospitals, grocery stores, etc.) in favor of more sustainable options such as composting and using waste food as animal feed.  The ban aims to reduce landfill waste and improve soil health by prohibiting businesses from throwing-away leftovers into landfills.  Vermont and Connecticut have similar legislation in place.  The future where we universally turn leftovers into soil amendment, may be just around the corner!


The Power of Perception

By: Evan Hughes
Sustainable Building Associate

“Don’t judge a book by its cover.” It’s something we’re taught at an early age that reminds us to keep an open mind and try new things. It may be a trite phrase, but it’s still a valuable piece of advice.

Having said that, it can be difficult to avoid forming judgments based on a quick first impression. It’s why you refuse to try the weird appetizer your friend recommended (it’s actually delicious).  Or why you might assume that the guy in the coffee shop wearing a scarf in July is insufferable and pretentious (he’s actually really down to earth). Or why you might assume that the pretty girl in your marketing class is out of your league (she totally is, I’m sorry.) Research conducted in the United States and Africa has shown that similar negative assumptions can influence the materials people choose when building a new home. One such material is rammed earth, an earth-building technique that involves compressing a mixture of soil, lime, and other additives between large wooden molds to form monolithic walls. A survey distributed to construction professionals in Kansas found that, while the appearance and environmentally friendly nature of rammed earth was perceived positively, its adoption had been limited by the assumption that it was antiquated and structurally unsafe.

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In Africa, similar surveys have revealed an association between earthen homes, low social standing, and poverty. The same surveys also show that people associate modern materials like concrete and steel with wealth and high performance. These associations create a vicious cycle where only the poor build with earth. Many of these people have no training in earth building and no background in engineering, so their homes may be more susceptible to erosion or structural failure. When these problems inevitably arise, it simply fuels the preexisting bias against earth, and the cycle continues.

Overcoming these negative assumptions takes time. It also requires that people, particularly contractors and material suppliers, work to understand the advantages and disadvantages of non-conventional materials. Knowing when, where, and how to implement environmentally friendly materials and methods can help increase the public’s awareness of their economic and environmental benefits, particularly in the residential construction market. Effective marketing is also critical to increasing awareness and market penetration of non-conventional materials. Tell a client that they should build with a certain material because it’s “the right thing to do,” and you may end up in a debate and possibly a fist fight, depending on where you are. Tell a client that they should build with the same material because it will save them money, lower their energy bills, and will make their home a more pleasant place to live, work, or raise children, and their response will probably be less combative and more inquisitive. It’s easy to label another person’s opinion as stupid or inconsequential. It’s more difficult to argue with the financial and material savings that sustainable materials have to offer.

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No one material is perfect for all climates and agreeable to all tastes. But by increasing awareness of alternatives to concrete, timber, fired brick, and steel, contractors can go a long way toward reducing the environmental and ecological impact of the construction industry. By doing research of their own, the public can better understand the advantages and disadvantages of non-conventional materials and make informed decisions based on hard data, rather than assumptions and first impressions.

Kraus, C. (2012). On perceptions of rammed earth. Rammed Earth Conservation, 157-162

Zami, M. S., & Lee, A. (2011). Inhibitors of Adopting Stabilised Earth Construction to Address Urban Low Cost Housing Crisis: An understanding by construction professionals. Journal of Building Appraisal, 6(3), 227-240.

Gooding, D. E., & Thomas, T. H. (1995). The potential of cement-stabilised building blocks as an urban building material in developing countries. ODA report, School of Engineering. UK: University of Warwick.

Using Biomimicry in Sustainable Design

By: Cassandra Kliewer
Sustainable Associate

Nature is the best learning tool. After generations and generations of improvement, nature has perfected itself to work best with its environment. Taking a closer look at an organism and the way it operates can inspire design. Janine Benyus, a biologist in the biomimicry world spoke about the innovative technologies inspired by nature: “learning about the natural world is one thing, learning from the natural world, that’s the switch.”

Biomimicry is designing technologies based upon natures’ sustainable strategies. When biomimicry is applied to design, efficiencies in energy, materials, and space are conserved. The people inventing these efficient designs range from professionals in the field, to students aiming to improve technology. In an effort to engage youth in the biomimicry community, Biomimicry 3.8 has created a competition for the best design inspired by nature.

Youth around the world have entered the challenge to design efficient technologies. The concepts in the challenge were inspired by their region-specific issues and applied natures’ efficiencies to create new technologies. Students from McGill University of Montreal, Canada addressed the problems related to cargo ships transporting organisms by inventing an air ballast system. Since cargo ships transport a lot of weight ballasting water was created to help a cargo boat stay afloat. Water is added when there is no cargo, and when there is cargo the water is released. The transfer of water to different bodies of water introduces non-region specific species. If the species is introduced to a region where it would thrive, it would become invasive and thus disrupt the ecosystem. The team from McGill proposed to replace the water with air. Filling the ballast tanks with air when the ship has cargo, and emptying the tanks when the ship is empty will replace the need for water. This design was inspired by the cuttlefishes’ ability to control buoyancy. Another team in Yucatan, Mexico designed a stable form of transportation. The alternative before this design was working tricycles which were unstable and inefficient. After study snakes movements, the team designed a quadricycle that operates via hand steering movements. At the Institute for the Built Environment (IBE) we strive to create efficiencies in construction to preserve the beauty of this planet. By using the U.S. Green Building Council rating system, IBE applies biomimicry technologies to construction projects. With construction comes options for implementation of new technologies. Everywhere you look in nature you can see efficiencies that have been improved over generations and generations. Some of the greatest inventions have been inspired by nature.

Green Globes: To Use or Not To Use?

By: April Brown & Helene Gotthelf
Project Managers

Ever since the General Services Administrationannounced their support of Green Globes in 2013, we’ve been eager to learn more about the rating system and test it out. We began brushing up on the Green Globes certification, watched a handful of webinars that became available, and even became Green Globes Professionals. From a high level view, Green Globes seemed to take everything that is cumbersome about LEED and toss it out the window.

Amidst the hype and excitement about an alternative to LEED though, we couldn’t ignore some of the critique that we had learned about Green Globes and the Green Building Initiative (GBI). This made us wonder – should the opportunity present itself, would we use and promote Green Globes?

In order to make a more objective decision, we researched the pros, cons, and costs of certifying a hypothetical building using Green Globes for New Construction – a 20,000 square foot addition to an existing art museum on a university campus.

Undoubtedly, there are several benefits of using Green Globes:  
  • The web-based tool includes an initial project evaluation which calculates your projected Green Globes score and provides instant feedback on your building. The online portal also tracks the status of the assessment process.
  • Green Globes includes a third-party site visit, which means that Green Globes Assessors can visually inspect the building and cut down on the amount of documentation you have to provide, which can save a lot of time for the project team. Additionally, the assessor is also available to answer questions about the assessment process, criteria, and documentation. 
  • Partial credit is allowed, recognizing varying levels of achievement.
  • Teams can choose credits that are “not applicable” to allow for project-specific and regionally-based conditions.
  • Green Globes incorporates ANSI-based Life Cycle Assessment
  • There are no precluding rules about certifying additions, as compared to one of the LEED Minimum Program Requirements that defines most additions as ineligible or requires very specific conditions for the addition to be eligible for certification. 
  • Hands-on and accessible customer service – according to correspondence with GBI staff, projects are assigned a project manager that will help answer any questions that may arise about the certification process from the moment that you begin.
There are also several disadvantages that play an integral role in the decision-making process:
  • There is no building performance data available to verify the correlation between Green Globes and a high performance structure.
  • There is a negative perception of GBI due to the type of corporations represented on their board of directors, mainly the timber and chemical industries. Many of the same organizations that support GBI have a long track record of fighting against environmental regulations.
  • Green Globes does not have any prerequisites. While this allows for flexibility in which criteria project teams choose to pursue, this may also allow project teams to exclude certain strategies that are imperative for high performance buildings, such as commissioning.
  •  BuildingGreen, an independent publishing company, has found that Green Globes is less technically rigorous than LEED. As a result, we question whether Green Globes will encourage the green building movement to continue to push the building and construction industry toward higher standards.
  •  There is less marketing and public relations potential. While Green Globes has received an increase in publicity over the past couple years, LEED is still the dominant green building rating system in the U.S.. With significantly less buildings pursuing Green Globes, we are unsure whether the certification will carry the same weight in the public eye as LEED.
According to GBI’s New Construction pricing list, the registration and certification fees will range from $10,500-$17,200. This does not include the price of certificates or plaques. The fine print for the Complexity Fee states that it is applicable for non-Energy Star building types and other multi-use/complex buildings that depart substantially from a standard office building. If applicable, GBI will notify customer of fee amount and whether the fee is optional or mandatory in advance of scheduling/performing services. GBI determines applicability in its sole discretion.
Due to a streamlined certification process, one would assume a cost and time savings for those gathering and submitting documentation. However, without having gone through the process ourselves, it will be hard to confirm whether this is true. Even if the consultant fees are reduced, the registration and certification fees are still much higher than LEED; therefore, the cost of certifying this hypothetical project (when compared to a LEED project of the same size and type) may end up as a wash for the owner.

After considering the advantages and disadvantages, we’ve decided that we cannot draw an objective conclusion about whether or not to use and promote Green Globes without gaining first-hand knowledge of administering the rating system ourselves. That said, we are intrigued enough to pursue a Green Globes project in order to make a well-informed conclusion on the credibility, rigor, and usability of this rating system. Until then, the question remains: to use or not to use Green Globes? What would you do?
Green Building Initiative (2014). Retrieved July 10, 2014, from
BuildingGreen. 2014. Green Globes vs. LEED Analysis [Webinar]. Retrieved from
Green Building Initiative. (2014). Green Globes Professional Training Manual.
General Services Administration (2014). Green Building Certification System Review. Retrieved July 9, 2014, from

No Difference in Occupant Satisfaction and LEED? Not so fast!

Associate Director
The Center for the Built Environment (CBE) at UC Berkley recently released a study in May 2014 suggesting that there is no difference in occupant satisfaction for LEED and non-LEED buildings.  Unfortunately, results like these can be easily taken at face value and are often misinterpreted by general audiences.
Upon further investigation and consideration of the study, there are a couple of important questions that should be raised about the construct, and ultimately the results, of the study.
Of the 15 IEQ parameters that the study assessed, only three are substantively addressed in the 2009 LEED for New Construction and Commercial Interiors credits: amount of light, air quality, and temperature.  The additional parameters center on cleanliness, maintenance, spatial design, and aesthetic, among others.
Light, air quality, and temperature are primarily addressed as credits in LEED, and not as prerequisites.  The CBE study does not indicate if the credits related to these attributes were achieved in the buildings evaluated in the study.  The study also included some buildings certified under the Existing Buildings: Operations & Maintenance rating system, which would include some additional parameters (e.g. building maintenance, workspace cleanliness), but even these attributes are a bit of a stretch.
Of the three areas that could arguably be addressed by LEED, responses were somewhat unfavorable related to amount of light in LEED buildings (likely related to energy conservation efforts), favorable for air quality (potentially due to ventilation and healthy materials credits that are included in LEED), and mostly neutral on temperature (which makes sense because thermal comfort is a key focus for any mechanical engineer who wants to cover his/her back on callbacks from unhappy owners).
So the first question is, “Is LEED even designed to affect occupant satisfaction?” I would argue that it is not.  LEED is primarily designed to 1) increase energy and water efficiency, 2) to encourage responsible site selection and development, 3) reduce impacts related to materials and 4) to create healthierbuildings for occupants.  Healthier is not the same as satisfied, as the two often include different factors, design solutions, and metrics for success.
A second point about methodology is that the researchers were primarily comparing Class A offices and institutional buildings to other Class A offices and institutional buildings.  One would argue that Class A design, is, well, Class A design.  That means that the starting point is already a pretty nice building, with decent designers and good mechanical systems.  Our experience on over 50 LEED projects would suggest that the pursuit of LEED generally doesn’t have much effect on decisions around furnishings, finishes, office layouts, etc. These types of design decisions are often dictated by programming and budget, and to a much lesser extent by LEED.
At the end of the day, I’m more concerned that the headlines and blog posts on this study will give people the wrong idea.  LEED really isn’t designed to affect the 15 IEQ factors that were measured in the CBE study.  LEED is, however, a great tool for adding focus and accountability for project teams to track and meet a whole host of relevant green building strategies.  Good design should not start with LEED; but through good design, prestigious certifications – and more importantly highly effective buildings – naturally follow.
A complete copy of the article published in Building and Environment can be found here.

The Benefits of Building Small

By: Evan  Hughes
Sustainable Building Associate

Americans like big stuff.  We have the biggest companies, the biggest cars, and, it turns out, the biggest houses.  According to a study of 18 countries conducted by Shrink That Footprint, an independent carbon-footprint research group, the United States was second only to Australia in average new home size and average floor space per person.  Home ownership, however, has become increasingly difficult in the post-recession economy.  This is especially true for recent college graduates, who may be saddled with debt or can’t afford a down payment.  For a prospective homeowner, or for anyone who wants to build their own home, small houses (under 1,000 square feet) present a number of advantages.


Small houses are cheaper

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Small houses require less material and time to build, and allow more money for higher quality interior finishes.  Small houses also require less energy to heat and cool, making them cheaper to own and occupy.  In extreme cases, money can also be saved when applying for a building permit.  For instance, in Chatham County, North Carolina, if the walls of a structure are no longer than 12’ on any side, a building permit isn’t required at all.

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Small houses are better for the environment

Many of these cost savings directly benefit the environment.  Building a small house uses less lumber and energy-intensive materials like concrete and brick.  Building small often means that more money can be spent on energy-efficient doors, windows, and HVAC equipment.  These features, combined with a smaller footprint, mean that small houses consume substantially less electricity than conventional homes, thereby reducing their contribution to the air and water pollution created by the coal-fired power plants.  Small houses also serve as a good platform for solar photo-voltaic systems, and can often use solar power and solar-hot-water systems for most, if not all, of their power requirements.

Small houses are easier to build

A first-time owner-builder or general contractor can get easily overwhelmed by the complexity of a residential construction project.  While building a house is rarely an easy, painless process, a small house is a much easier project to tackle than a conventional 2,000-4,000 ft.² suburban home.  Small houses don’t typically feature complicated mechanical systems, plumbing arrangements, or electrical wiring, and small house construction does not typically call for large structural beams and columns that require heavy equipment to put in place.
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Houses are a lot like cars.  Both serve basic needs.  Both are often seen as extensions of their owners.  Whether buying a car or a house, many consumers believe bigger is better.  However, just as a smaller car can be an equally fulfilling and eminently more practical choice for most car buyers, a small house (under 1000 ft.²) uses less energy, requires less material to build, and, if a bit of creativity is exercised during the design phase, can be just as practical and beautiful as a house twice its size.  In short, by reducing the size of their house, an owner-builder reduces the complexity, the expense, and the environmental impact of their project.

A Personal Small Step to Sustainability

By: Anderson Lewis

When someone makes a conscious decision to live more sustainably, it is easy to get discouraged by the mindset of “I’m just one person. What difference can I really make?” But when it comes to being sustainable, the Axiom “ the little things make the biggest difference” can certainly hold true.  Don’t get me wrong; I still think much has to be done before humanity can reach a state of benign or regenerative interaction with our natural environment. However, it is dangerous for us to assume that our seemingly small actions do not have a meaningful, positive impact.  For example, it is easy to equate turning the lights off when you leave the room to saving a few cents. No big deal, right?  However, when you factor in the process energy used to harvest and transport the raw material used to create your energy, the transmission losses from power lines, and all the carbon emissions associated with this overall process, it makes turning off the light seem more important.
Having the ability to measure the positive impacts of your sustainable actions and track your progress is a great motivator to continue being more sustainable.  Knowing where you started from (your initial energy usage, water usage, etc.) gives you a baseline to compare improvements against (aka benchmarking).  This allows you to see if your changes (actions, energy retrofits, etc.) are indeed positive and can help guide your decisions on where to focus future actions to make the largest impacts.  Lastly, associating your sustainable accomplishments (energy saving, water savings, etc.) with an easily comprehensible reference can make them more palpable and rewarding.  For example, it is hard to know if saving 1 kWh is good or not, but when you consider that 1 kWh could power a T8 fluorescent lamp for 31 hours and 15 minutes, it gives greater context to your accomplishments.
At IBE, we have been diligent about tracking information from the projects we have worked on.  This historic data is helpful to us in multiple ways.   First, it allows us to compare and contrast different project types and their performance and to monitor how the sustainability of our projects has progressed over the years. This helps us know that we are on the right track to higher levels of sustainability. Second, this historic data acts as a marketing tool for the IBE, allowing for us to more easily convey the benefits of our services to clients and more accurately predict what type of performance and savings our clients should expect. Lastly, when this historical data is put in easily understandable terms or comparisons, it can really act as a motivator for IBE staff/project stakeholders and affirm the fact we are making a meaningful positive impact.  For example, in total, projects that the IBE has been involved on have diverted over 15,000 tons of waste material from the landfill (the equivalent weight of 60 statue of liberties).  These materials were recycled and reused in various ways and reduced the amount of raw materials that would have been harvested to meet the needs that this recycled material filled. In addition, the aggregate of IBE projects on average save approximately 95 million gallons of water a year (enough to fill 143 Olympic sized swimming pools (assuming a 2 m depth).
If these aforementioned accomplishments seem large, well, it’s because they are! And this is before considering the added energy/carbon savings that come from not having to harvest, transport raw materials to produce new materials or to treat and transport the water saved.  At IBE we are proud of our accomplishments but recognize that there is still so more to be done.  We will not rest on our laurels and encourage you to do the same.
In the global scheme of things the changes we have helped instate might be small but they are far from insignificant. If everyone were to view their own actions in this way then all these small actions will add up to one big change.