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What Makes a Product Green?

 
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Lots of manufacturers call their products “green,” but are they? Here’s our guide to the high-performance attributes that matter.

O Ecotextiles Ranier upholstery fabric

By the GreenSpec Team

When EBN started publication 20 years ago, simply finding building products designed with environmental benefits in mind was a big challenge. We tackled that challenge in the late 1990s by developing GreenSpec, our guide to the best-of-the-best green building products, and throughout the 2000s we watched the explosion of manufacturing—and marketing—of “green” products. We’ve kept pace with environmental attributes of products in many ways, including a partnership with Healthy Building Network and its Pharos tool, which offers a deep dive into product ingredient safety.

As we have evaluated thousands of products throughout this period, asking whether they are exceptional enough for listing in GreenSpec, we have had countless discussions about what makes a product green. Our touchstone has been something we call “Green Attributes”—a set of broad criteria and definitions, knit together with life-cycle thinking. Translated into the practice of design and construction, they help distinguish green from greenwash, evaluate the relative greenness of different product alternatives, and make appropriate product selection choices to ensure a high-performing, healthy building with the lowest possible impact.

The explosion of green building has meant, among other things, a constantly rising bar for green products and materials along with more and more information on how the built environment affects human and ecological health. Enough has changed, in fact, that we’ve decided to update our readers on our understanding of just what makes a product green. We welcome input in this process of determining just what is green and how that determination plays out in specification and procurement.

Efficient Use of Materials

The surest way to reduce the environmental impact of a material is simply to use less, usually by design. Examples include smaller buildings with efficient use of space, building reuse, designs that accommodate adaptation, and structure as finish.

Product selection can also help: there are products that serve their function using less material than the standard solution and products that are especially durable and therefore won’t need replacement as often. Efficient use of materials also means moving from linear “cradle-to-grave” to cyclic “cradle-to-cradle” use of materials. As William McDonough, FAIA and Michael Braungart, Ph.D. have championed, rather than going to waste, the product or its materials should remain in use or be reintroduced into biological cycles. Products that are designed to be reusable, recyclable, or compostable facilitate this trend.

Durable or low-maintenance

These products are environmentally attractive because they need to be replaced less frequently or their maintenance has very low impact, both of which can reduce costs as well as environmental impact.

Robust answers on typical service life of products can be hard to come by, however. In GreenSpec we reserve this criterion for products where the material is clearly more durable than alternatives, such as an exceptionally traffic-resistant polyurethane floor finish. We refer to standardized tests for durability when they are available and appropriate.

RetroPlate concrete polishing system

We also consider “appropriate durability”: long life is more important in a building envelope than in interior finish materials that will be replaced for aesthetic reasons. Here, reduced maintenance can be particularly important. An example is resilient flooring that doesn’t require regular waxing—an unnecessary use of resources and a health hazard.

Reduces material use

Some products help us use other products or materials more efficiently. For example, drywall clips allow the elimination of corner studs, engineered stair stringers reduce lumber waste, and concrete pigments and polishing systems can turn concrete slabs into attractive finished floors. We also recognize some products, like vacuum plumbing systems, which use less material than their conventional counterparts. Many products with this attribute are fairly unique, so we bring a skeptical eye to manufacturer claims, but not a specific standard.

Salvaged content

By reusing products and materials, we conserve resources and energy. It can be challenging to ensure that salvaged material can meet performance requirements, so it’s common to see this material used decoratively (when doing so, watch out for hazards like lead paint).

Manufacturers of reclaimed wood products often tout their sustainability, but as with other resources, the supply of reclaimed wood is limited. The market for reclaimed wood can lead to unique concerns, such as the premature demolition of historic barns and other buildings, or “sinker log” reclamation practices that are illegal or compromise river bottoms. The Rainforest Alliance’s SmartWood program is available for reclaimed wood, as is as the Forest Stewardship Council (FSC) label, although few salvage operations are currently certified. In the absence of certification, take a close look at company protocols to ensure that reclaimed wood is appropriately sourced.

Reusable, recyclable, or compostable

Products designed to be reusable, recyclable, or compostable have the potential to help us make efficient use of materials, but manufacturers sometimes exaggerate when using these terms. Fortunately, the Green Guides from the Federal Trade Commission (FTC) provide basic definitions. Almost any product could arguably be recycled into something, so FTC specifies that there must be an established market for the material. Similarly, compostability depends on the availability of the right composting facilities (usually industrial) needed to process the material.

Responsible Sourcing

The industry is increasingly scrutinizing manufacturing supply chains and raw material sourcing for environmentally and socially responsible practices—a trend we hope to see continue and increase in rigor. For now, we consider the most responsibly sourced materials to be those that use recycled content, come from agricultural waste, or are renewable materials for which standards ensure a reasonable level of sustainability. Extracting raw materials, even in industries that have tried to clean up their act, takes a toll on the environment through ecological impacts, land-use issues, energy use, and many other areas—but if only nonrenewable materials are appropriate, try to purchase from companies with more responsible corporate practices.

Post-consumer recycled content

Bensonwood Homes

Using materials recovered from the waste stream typically results in less waste, pollution, and energy use than using virgin materials. From an environmental standpoint, post-consumer is typically considered preferable to pre-consumer recycled content because post-consumer recycled materials are more likely to have been diverted from landfills.

In some cases, we consider products with recycled content green but with some caveats regarding where they should be used. For example, rubber flooring made from recycled automobile tires should not be used in most fully enclosed indoor spaces due to the likelihood of VOC emissions.

Recycling can have downsides. For example, studies show that some curbside collection programs and recycling processes use more energy than they save. Closed-loop recycling is generally preferable to “down-cycling,” in which a lower-grade material is produced—but due to contamination of waste streams and the difficulty of extracting high-value ingredients, down-cycling may be as good as it gets. At times recycling can re-introduce hazardous components. Some products, like copper and aluminum, include a high level of recycled content as a matter of course—which we applaud but don’t consider justification for listing in GreenSpec. As more complete life-cycle information on recycled materials and processes becomes available, we use that to increase our scrutiny of recycled products.

Pre-consumer recycled content

Pre-consumer (also called “post-industrial”) recycling refers to the reuse of industrial by-products, as distinguished from material that has been in consumer use. The iron-ore slag used to make mineral wool insulation and the fly ash used to make concrete are examples of post-industrial recycled materials. While post-consumer recycled content is preferable, a product that recycles seldom-used waste materials—especially in an area where recycled products are hard to find—or uses pre-consumer content can be considered green.

Excluded from this category, by FTC definitions, is the use of scrap within the same manufacturing process from which it was generated—material that would typically have gone back into the manufacturing process anyway.

Biobased and sustainably sourced

Growing and harvesting our building materials would be a great way to move toward a closed-loop system rather than a linear path from extraction to disposal. Doing so holds the promise of true sustainability and regeneration of ecosystems instead of damage to them.

Plyboo bamboo flooring

Unfortunately, biobased materials today can be at least as problematic as any other material. Intensive land use, chemical use, fuel use, nutrient runoff, and other pollution are among the impacts of agriculture; add to that competition between food crops and those used for building materials or fuel. We would like to see sustainable use of biobased materials, but improving practices and figuring out how to assess and document more sustainable practices will take a long time. There is no ready equivalent to FSC for biobased materials that aren’t wood, although certification to “organic” standards or other sustainable agriculture standards can provide guidance in some cases.

At the same time, we don’t want to exclude biobased products that are typically responsibly sourced just because they don’t have a certification—particularly where they replace more problematic materials. GreenSpec continues to prefer rapidly renewable alternatives to materials that present greater concerns. Examples of rapidly renewable materials in GreenSpec include linoleum, cork, and textiles such as wool, sisal, and organic cotton.

Certified wood

Third-party forest certification based on standards developed by FSC is the best way to ensure that wood products come from well-managed forests. Wood products must go through a chain-of-custody certification process to carry an FSC stamp. With a few exceptions, any non-salvaged solid-wood product and most other wood products must be FSC-certified for us to consider them green.

Uses agricultural waste

We consider agricultural waste materials such as straw—the stems left after harvesting cereal grains—to be a good alternative to conventional materials. Such materials might otherwise be wasted, and using them makes the most of agricultural crops.

Energy and Water Conservation

The ongoing environmental impacts that result from energy and water used in operating a building often far outweigh the impacts associated with building it. Many products are included in GreenSpec because they contribute to energy or water conservation. Also included here are products that contribute to a facility’s ability to renewably generate power onsite.

It’s important to note that as buildings become more efficient, the embodied energy, carbon, and water of the products that make up the building become increasingly significant. Dealing with operational energy use remains a top priority, but as we begin to aim for zero impact it will be increasingly important to consider embodied impact at the same time.

Reduces heating and cooling loads

Foamglas cellular glass insulation

Before specifying efficient heating and cooling equipment, it’s important to do what we can to reduce heating and cooling loads. Insulation is one of the key products to consider here, but because there are so many insulation products on the market, we look for additional benefits. Examples include cellulose insulation with recycled content, mineral wool insulation with no flame retardants, and fiberglass insulation with no formaldehyde binders. Other products in this area are high-performance windows and glazings, products that contribute to building airtight envelopes, products that reduce thermal bridging, and window-retrofit products.

With products in this area under constant development, we are always refining our approach. For example, as we have learned about insulation products with hazardous flame retardants and blowing agents that have high global warming potential, we have removed those products from GreenSpec, pending manufacturing changes. We encourage building professionals to pressure manufacturers for those changes through specification language and purchasing decisions.

Energy-conserving equipment

With most energy-consuming equipment, such as water heaters, furnaces, and refrigerators, we have good data on energy consumption and can set clear standards accordingly. Energy Star standards exist for dozens of equipment types, but too often these standards allow for a much higher proportion of products to qualify compared with the 20% that is the program’s stated goal. The Consortium for Energy Efficiency provides deep analysis of how far above Energy Star the market is achieving and provides a better measure of green in areas where it has thresholds.

Some product categories, like LED lighting, have exploded with dozens or even hundreds of manufacturers putting out products of unknown quality. Because the energy performance of the equipment we specify is a long-term proposition, we tend to focus on companies that have a demonstrated track record of bringing good products to market and keeping them there while achieving top-notch performance specifications. In some cases, products that meet the energy-efficiency requirements are excluded because of evidence of poor performance or durability.

Conserves water

All toilets and most showerheads today meet the federal water-efficiency standards, but not all of these products perform satisfactorily. With toilets and showerheads, we include products that meet or exceed WaterSense standards, which include performance requirements—although we go beyond WaterSense where there are issues not adequately addressed by the program. We also look for other products that conserve potable water, such as rainwater catchment and graywater recovery and reuse systems.

Renewable energy equipment

Equipment and products that enable us to use renewable energy instead of fossil fuels and conventional electricity are highly beneficial. Examples include solar thermal systems, solar electric (photovoltaic) systems, and wind turbines. Other power generation equipment, such as fuel cells and some energy storage systems (like batteries) are included here because they help us accommodate varied energy sources so that we may eventually move beyond fossil-fuel dependence.

Low-Impact Operations

Eco-Tek porous pavers

Reducing waste, pollution, and other impacts of building operations and maintenance has become an increasingly strong focus of the green building industry. GreenSpec has always considered products contributing to these goals green.

Reduces construction impacts

Included here are various erosion-control products, foundation products that eliminate the need for excavation, and exterior stains that result in lower VOC emissions into the atmosphere. Fluorescent lamp and ballast recyclers and low-mercury fluorescent lamps reduce environmental impacts during maintenance and disposal of luminaires.

Reduces operational pollution or waste

Alternative wastewater disposal systems reduce groundwater pollution by decomposing organic wastes or removing nutrients more effectively. Hand dryers reduce water and paper towel use, alternative treatments for cooling tower water reduce chemical use, and carpet tile allows modular replacement of worn areas. In screening products for this area, we focus on quantifiable environmental benefits and strong performance records.

Reduces stormwater pollution

Stormwater runoff from the built environment, often mixed with contaminants, has a damaging effect on local and downstream ecosystems. Porous paving products and vegetated roofing systems result in less rainwater runoff and thereby reduce surface water pollution. Stormwater treatment systems reduce pollutant levels in any water that is released. Again, quantifiable benefit and a strong track record are important here.

Reduces pesticide treatments

Periodic pesticide treatment around buildings can be a significant health and environmental hazard. Green alternatives obviate the need for pesticide treatments. Examples include physical termite barriers and bait systems that apply toxins in a much more targeted way than broad-based pesticide application.

Healthy Buildings

AllSun Tracker

Buildings should be healthy to live or work in and around—for humans and other living creatures—and product selection is a significant determinant of that. We look at several categories of green building products that help to ensure a healthy built environment.

Improves light quality

Besides saving energy, natural daylight is beneficial to our health and productivity. We consider as green products that enable us to bring daylight into a building, including specialized commercial skylights, fiber-optic daylighting systems, lightshelves, and tubular skylights.

Improves acoustical performance

Background noise, whether from indoor or outdoor sources, adds to stress and discomfort, and poor acoustical design inside can exacerbate problems from background noise and reverberation of sounds. Products that absorb sound and prevent sound transmission can be considered green, although there are so many such products available that we also look for especially innovative products as well as products with additional green attributes such as recycled content and strong energy performance. We also look for sound-masking systems with exceptional performance characteristics.

Prevents moisture or air-quality problems

Moisture brings durability and air- quality problems with it, and myriad green products are designed to manage it and keep it out. Given the variety of products available, we look for those that meet key performance standards and that make sense in a whole building assembly—such as vapor-permeable weather-resistive barriers that not only prevent moisture from entering the building envelope but also allow drying when the envelope gets wet.

Low-emitting

Just how low the VOC level needs to be for a given product to qualify for inclusion in GreenSpec depends on the product category. For most products, we require certification to California’s health-based emissions standard, CDPH Standard Method v1.1 (also referred to as California Section 01350), which tests a product’s resultant VOC concentrations in the space after a given period of time. For wet-applied products like paints, caulks, and adhesives, we also look for VOC content instead of, or in addition to, verified low emissions; this is because emissions testing doesn’t adequately test initial offgassing, and VOC content is currently the only widely available proxy.

Avoids hazardous ingredients

Lifeline resilient flooring

Some materials provide a better alternative in an application dominated by products for which there are concerns about toxic constituents, intermediaries, or by-products. For example, form-release agents are a good alternative to products that contaminate water or soil. With the panoply of products made with polyvinyl chloride (PVC) and brominated flame retardants, some products are green simply because they provide an alternative. Examples of this are natural wall coverings, drain and vent piping, and roofing membranes. Some green products are free of hazards common to the product category; for example, LED lighting is inherently free of the mercury found in fluorescent lighting sources.

However, it’s worth noting that without transparency about actual ingredients (see more on transparency below), there’s no guarantee that a product won’t have less-common or less-well-known hazards that the manufacturer isn’t talking about. We use Pharos’s Chemical and Material Library to assess less-well-known hazards, and we encourage manufacturers to review the hazardous properties of all chemicals they use and to seek out safer materials.

Improves air quality

Once we’ve considered low-emitting products and those that prevent moisture problems, we also consider green ventilation products, filters, radon mitigation equipment, and other equipment and devices that help to remove pollutants or introduce fresh air. Because ventilation equipment is standard, we only recognize products that are particularly efficient or quiet or that have other benefits, such as heat recovery.

Monitors indoor environmental quality

Some products are “green” because they help us monitor the indoor environment. These include carbon monoxide (CO) detectors, lead-paint test kits, and other IAQ test kits or devices. Because some products, such as CO detectors, are so common, we look for evidence of superb performance or other features in order to consider them exceptional enough for listing in GreenSpec.

Sustainable Industry, Resilient Communities

Left: Ice Bear 30 hybrid air conditioner. Center Top: Aqua2Use graywater system. Center Bottom: NyloDeck recycled decking. Right: Knight Wall rainscreen system.

It’s not just what’s in the product or what it does. Products can also be considered more or less green depending on the activities of the manufacturer and supply chain or because of their role in helping to build more resilient communities. Some of these benefits are local: you may know by reputation companies in your area that contribute to community well-being through employment and procurement practices.

Information transparency

As we recently explored in EBN (see “The Product Transparency Movement,” EBN Jan. 2012), better information alone doesn’t make a product green, but it does make it a lot easier to see just how green it is. That transparency, in turn, can encourage manufacturers to clean up their act.

While a company could be completely transparent about a harmful product, we consider transparency a secondary green attribute—whether manufacturers voluntarily report on company practices through the Global Reporting Initiative or have released information on particular products through Environmental Product Declarations (EPDs), Health Product Declarations, full disclosure of ingredients in Pharos, or other systems. We also look for products where clear information is provided on embodied water or embodied carbon—also referred to as “carbon footprinting.”

Reduced manufacturing impacts

Four Steps to Greener Specs

It may be that the product itself was redesigned to require less-hazardous inputs or use raw materials with lower embodied carbon, or perhaps the manufacturing process was redesigned to reduce waste, emissions, and material or energy inputs. The green chemistry movement is pushing manufacturers to redesign products to avoid hazardous inputs in the first place. However it’s accomplished, products with reduced manufacturing impacts relative to alternatives tend to be environmentally preferable.

We look for clear demonstration of reduced impact, either through precise accounting of manufacturing practices relative to the norm, robust life-cycle assessment, significant demonstrated reduction of hazardous emissions during manufacture, or other means. Since there are so many ways that manufacturers could reduce impact—and not all of them are rigorous enough for us—we scrutinize claims carefully and look for approaches supported by industry stakeholders, such as the move by leaders in the field tocreate reliable embodied carbon metrics.

Responsible corporate practices

Preferentially purchasing from responsible companies increases the impact of green procurement by making it clear that it’s no longer possible for a manufacturer simply to create one product for a niche “green” market while continuing business as usual with other product lines. It is increasingly possible to evaluate corporate responsibility based on voluntary reporting systems, corporate scorecards generated by watchdog groups, or new standards such as UL 880. Evaluating broader social impacts of a specific product’s manufacture remains challenging, but at a corporate level such evaluations are much more feasible and meaningful. Lastly, we take a dim view of manufacturers that claim to produce green products while actively lobbying against legislation that addresses climate change and other issues. You can’t get a clean product from a dirty company.

Provides connection to nature

Biophilia—a love for nature—is an important consideration in building design and is also relevant to product selection. Biophilic elements that help connect us with nature provide real, measurable benefits relative to such human performance metrics as productivity, emotional well-being, stress reduction, learning, and healing (in healthcare settings). While truly natural elements are considered ideal, it appears that even simulation of natural features can have some beneficial impact (see “Biophilia in Practice,” EBN July 2006). We consider biophilia mostly as a secondary attribute of products that are considered green for other reasons, but we will occasionally consider products solely based on this attribute as long as they don’t come with additional environmental concerns. An example is energy-efficient lighting for healthcare settings that mimics views to the sky or the outdoors.

Enhances community well-being

Looking beyond the walls of a building, many products can contribute to safer neighborhoods, improved walkability, and making high-density communities more appealing. We look for innovative products that support the greening of public spaces, facilitate high-density development, make alternatives to automobile transit more feasible, or otherwise contribute to the quality of outdoor spaces.

Increases resilience

While resilience—the ability to weather natural disasters and maintain livable conditions in the aftermath of disruptive events—is mostly an issue of building design and community preparedness, certain products can help. For example, almost all heating systems require electricity to operate even if their primary fuel is oil, gas, or wood pellets; systems that allow operation even if grid electricity is not available are more resilient in the event of power outages. Rainwater harvesting, water storage, composting toilets, and waterless urinals contribute to resilience not only in drought-prone areas but also during power outages in any home dependent on well water. Solar water heating systems that can operate without utility power, and back-up power systems that are more energy-efficient than standard generators, may have this attribute.

Applying These Criteria

Our aim through GreenSpec is to balance pragmatism, precaution, and vision to create a useful guide for those specifying products that contribute to high performance in building projects. Consistent guidelines also help steer the industry toward safer, more environmentally friendly products. The overarching criteria outlined here provide high-level guidance for our selection decisions for GreenSpec, and we hope they’ll do the same for your product procurement and specification efforts. We also hope to advance the development of new, greener products.

Just having green performance attributes on a project team’s radar isn’t enough. These attributes need to become part of the DNA of project teams, as suggested by Gensler’s Ritchie, taking their rightful place alongside other vital performance attributes—such as aesthetics, cost, and functionality—as part of an integrated, life-cycle approach that looks to achieve the greatest benefit possible within the context of the project. At its best, this kind of thinking flows from early design stages through specification and all the way into construction. Susan Kaplan, director of specifications and sustainability at HLW International, teaches designers to stay project-focused when identifying green priorities and then write that into specifications. “Ask for what you want,” she says, because “if you don’t ask, you probably won’t get it.” Kaplan also notes, “Once you pick something, it’s not over; you have to teach the contractor what you want and how to get it.”

Getting Priorities Straight

While this article outlines the overarching criteria used in GreenSpec, each product category in the guide lays out which of these criteria we consider most relevant for that category, based on available information. For example, with lighting fixtures, energy efficiency is most important, mercury content less so, and recycled content in the housing the least relevant. For fabrics, water consumption and dyeing processes are key; for carpet it’s the raw fiber; and for HVAC it’s typically energy use. The product category also lays out what specific thresholds a product must achieve to get listed—so, for example, recycled content may be enough for plastic site furnishings but virtually ignored for HVAC equipment. It is these details that can be refined for use in specifications.

Our tactic with GreenSpec is to identify quantifiable, easily verifiable standards where those can be defined and then base other decisions on case-by-case examinations of products. In some product categories, such as energy-consuming appliances and VOC-emitting paints, specific thresholds can be established relatively easily, particularly if rigorous third-party environmental certifications are available. But for many criteria—like reduced material use—the lines are much fuzzier, and more judgment calls are required. We hope that this article helps you gain the understanding needed to be more confident about the judgment calls you’re making on projects. We welcome your feedback in the comments section and at research@BuildingGreen.com.

Continuing Education

Receive continuing education credit for reading this article. The American Institute of Architects (AIA) has approved this course for 1 HSW Learning Unit. The Green Building Certification Institute (GBCI) has approved the technical and instructional quality of this course for 1 GBCI CE hour towards the LEED Credential Maintenance Program.

Learning Objectives

Upon completing this course, participants will be able to:

  1. List and describe at least three attributes that address each of the following categories: "efficient use of materials"; "responsible sourcing"; "energy and water conservation"; and "low-impact operations."
  2. List and describe at least five attributes that address both of the following categories: "healthy buildings" and "sustainable industry, resilient communities."
  3. Combine the overarching criteria with the high-level guidance for GreenSpec selection decisions to further green product procurement and specification efforts.
  4. Recognize ways in which one might use such criteria to advance the development of new, greener products.

To earn continuing education credit, make sure you are logged into your personal BuildingGreen account, then read this article and pass this quiz.

Discussion Questions

Use the following questions to inform class discussions or homework assignments.

  1. The article addresses the goal of transitioning from a linear “cradle-to-grave” to a cyclic “cradle-to-cradle” use of materials. Considering the manner in which GreenSpec and the Pharos Project have linked their websites to provide a single, authoritative source for specifying green building products, what might a collaboration look like that tackles the end-use stages of products?
  2. There’s a desire to see more sustainable uses of biobased materials but improving practices and figuring out how to assess and document them is challenging. What standards besides “organic” might influence this developing area? What factors might be addressed to help speed the process?
  3. The article mentions how certain products may be considered green but with caveats, such as where to use them. How far should caveats be taken? Should, for example, a caveat be placed with recycle bins, stating how studies show that curbside collection programs and some recycling processes use more energy than they save?
  4. As buildings become more efficient, their products’ embodied energy, carbon, and water gain significance. Discuss this trajectory in terms of transparency. What are or will be some challenges with third-party verification?

February 1, 2012

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IMAGE CREDITS:
1. Photo: O Ecotextiles Inc.
2. Photo: Manhattanville College
3. Photo: Bensonwood
4. Photo: Alex Maness
5. Photo: Foamglas
6. Photo: R.I. Lampus Company
7. Photo: AllEarth Renewables
8. Photo: Upofloor
9. Photos: Ice Bear, Water Wise Group, NyloDeck, Francis Zera/zeraphoto
10. Source: BuildingGreen, Inc.
11. (no credit)
12. Source: BuildingGreen, Inc.
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