Summary and critique of "LEED" Building Design & Construction Reference Guide, v4

Jonathan Ochshorn

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Following is my summary and critique of the USGBC's LEED Building Design & Construction Reference Guide, v4. Commentary on the Reference Guide can be found in these red boxes, sometimes within each of the chapter links immediately above, but also in my summary and critique of the prior versions: Version 2.2 NC and Version 3.0.

6. Materials & Resources (MR)



Life Cycle "Assessment" (LCA):

What is a "product"?

MR Prerequisite 1: Storage and collection of recyclables

Intent: Reduce landfill waste.

Requirements: Collection/storage area provided in building for recycling materials. In addition to dealing with paper, cardboard, glass, plastics, and metals, this prerequisite also mandates dealing with two of the following three things: batteries, lamps with mercury, and e-waste.

MR Prerequisite 2: Construction and Demolition Waste Management Planning

Intent: Reduce landfill waste originating from construction or demolition debris.

Requirements: Make a plan that considers at least 5 "material streams" (excluding land-clearing debris). That's all: just make a plan.

MR Credit 1: Building Life-Cycle Impact Reduction (2-5 points)

Intent: Improve "environmental performance" of materials/products; encourage adaptive reuse of buildings.

Requirements: There are four options, only one of which can be (needs to be) satisfied to get points.

The alleged value of building reuse, rather than new construction, is based in part on a 2011 report on The Greenest Building cited in the v4 Reference Guide. This report shows that impacts of Global Warming Potential (GWP) are, or are not, mitigated by reuse (as opposed to more energy-efficient new construction) depending on the climate, the type of occupancy, and the number of years that new construction would need to be in place to offset the carbon costs of demolition and construction — i.e., the GWP impact mitigation of new construction, based on its more efficient energy profile, requires anywhere from 10 to 80 years (or "never" in the case of warehouse conversions into residential uses) of lifespan. Aside from the enormous variation in outcomes, and in spite of the limited environmental impacts considered (GWP only), what this type of study completely neglects to consider is the global growth of fossil-fuel-derived energy use. Whether an individual project chooses to reuse and renovate, rather than building new, is a useless metric for assessing global environmental impacts, since the sheer mass of new projects, whether adaptive reuse or new construction — and therefore the continual increase in fossil fuel use and greenhouse gas emissions — renders such distinctions moot.

MR Credit 2: Building Product Disclosure and Optimization — Environmental Product Declarations (1-2 points)

Intent: Encourages the use of products/materials that are environmentally sound, based on life-cycle assessment (LCA) documentation produced by product/material manufacturers.

Requirements: There are two options, each worth a point, and each independent of the other, so that both may be achieved.

MR Credit 3: Building Product Disclosure and Optimization — Sourcing of Raw Materials (1-2 points)

Intent: Encourages the use of products/materials that meet "triple bottom line" criteria and, in particular, have been extracted or "sourced" in a "responsible manner."

The so-called triple bottom line presumes that businesses may make decisions on the basis, not only of profitability, but also on the basis of environmental or social considerations. This is clearly false, since only profitability ensures the survival ("sustainability") of the business within a competitive capitalist marketplace. Any social or environmental efforts that reduce profitability threaten the viability of the business itself, and therefore would never be undertaken. Social or environmental measures enter into the marketplace via governmental regulations that apply to all businesses (e.g., clean air act or child labor laws). That businesses may decide to enter a market niche with environmental or socially-conscious attributes has nothing to do with any triple bottom line: rather, such businesses have simply decided to compete within a market — still governed by the single "bottom-line" criterion of profitability — in which environmental or social factors are recognized as opportunities for making money.

The "bottom line" is, literally, the bottom line of a business ledger in which expenses and income are tabulated; a positive value on the bottom line indicates profit. In this literal sense, a business could well create some sort of "social" and "environmental" ledger, in which expenses and social/environmental outcomes were tabulated, and a triple bottom line could thus be established. The problem with this concept is two-fold. First, all "expenses" devoted to social or environmental causes would, by definition, show up in the "financial" ledger, since the investment of capital — for whatever reason — is a financial matter: it is not possible to remove "social" or "environmental" expenses from the financial bottom line calculation. Second, the bottom line concept — taken literally — is simply a measure of whether the business is "in the black" or "in the red." From this neutral standpoint, a social or environmental "bottom line" could similarly attempt to measure the social or environmental impacts for which the business is responsible. However, such a "neutral" reading of the bottom line — as a mere tool for measuring various parameters — misses the actual meaning that the term has come to embody: it is not simply a tool for measuring impacts, but an imperative to successfully compete by taking all viable measures to cut costs of production and improve profitability. The bottom line is the life or death struggle for survival that compels businesses to search the globe for the cheapest sources of labor, materials, and energy. It is in this latter sense that the concept of a triple bottom line is meaningless, since there are no such "life or death" factors that compel businesses to achieve particular social or environmental outcomes. Instead, all such noble endeavors are quickly transformed into line items within the financial ledger, justified by any number of business calculations concerning the economic value of well-publicized good deeds.

Requirements:There are two options, both of which can be achieved for a total of 2 points:

MR Credit 4: Building Product Disclosure and Optimization — Material Ingredients (1-2 points)

Intent: Encourages the use of products/materials that meet "triple bottom line" criteria [see red box comments above] and, in particular, limit the amount of harmful substances used in the product, and provide better life cycle assessment (LCA) outcomes.

Requirements: There are three options, each worth 1 point. The stated total limit for this credit is 2 points, even though 3 points seem possible by adding up the points gained in the separate options, which are as follows:

According to LEED instructions for this credit, products satisfying either Option 2 or Option 3 can be combined to reach the 25% cost threshold, but any given product can only be counted in one of these two "cost-based" options. This, at first glance, would appear to make it somewhat more difficult to satisfy the criteria for all three Options. But it still seems technically possible to satisfy all three options and thereby gain 3 points: for example, Product A could represent 25% of product costs and satisfy Option 2; while Product B could represent 25% of product costs and satisfy Option 3; and Products A, B, C, D, etc. could satisfy the criteria for Option 1 (20 products whose ingredients are measured...). However, the "step-by-step" explanation reiterates that only 2 points are possible for this credit. Products constituting structure and enclosure are limited to 30% of the total cost of products that can be considered in Options 2 and 3.

MR Credit 5: Construction and Demolition Waste Management (1-2 points)

Intent: Like Prerequisite 2, the intent is to reduce landfill waste originating from construction or demolition debris.

Requirements: There are two options for compliance, all of which exclude land-clearing debris or excavated soil. Wood that is not recycled, but rather burned as fuel, can be considered; whereas other "waste-to-energy" materials cannot be counted unless they comply with European standards promulgated by the European Commission (2008/98/EC and 2000/76/EC) and the European Committee for Standardization (EN 303). The options, only one of which may be selected, and which are based on the "plan" created in the corresponding prerequisite, are as follows:

The lack of coherence in these credits is evident in the two options for construction waste mitigation. If the second option is too rigorous, limiting the amount of construction waste based on the building's size, the first option can generate the same number of points irrespective of the amount of waste that ends up in a landfill, especially if, and to the extent that it eludes the primary goal of source control. Take the 50,000 square foot building used as an example above. Let's say that instead of creating 62.5 tons of construction waste (and thereby satisfying the criterion for Option 2), we create ten times that amount — 625 tons of waste, or 25 pounds for each square foot of floor area. It's still possible to gain 2 points under Option 1, "path 2," as long as 75% of this waste, or 469 tons, is "diverted" from landfill. In other words, 156 tons of waste could still be headed for a landfill — more than twice the amount allowed under Option 2 — but the two points are still awarded. In fact, there are no limits to how much construction/demolition waste can end up in a landfill while still gaining points under Option 1: all that is required is to implement as little source control as possible, thereby increasing both the amount of waste generated and the amount of waste that can be sent to the landfill while still complying with the credit's requirements.

It is also possible to game the system by using either a "volume" metric or a "weight" metric, since certain recyclable materials are much lighter than others relative to their volume (e.g., paper, plastics, clean wood compared to concrete scrap). For example, if we had 10 cubic yards of recyclable corrugated cardboard, 10 cubic yards of recyclable concrete scrap, and 25 cubic yards of some other non-recyclable waste material weighing 18,500 lbs, we couldn't gain any points under Option 2 if we measured by volume: (10 + 10) / (10 + 10 + 25) = 44% diversion (less than the required 50%). However, if we use the weight metric, the calculation turns out to be more favorable: 1000 lbs of cardboard + 18,550 lbs of concrete / (1000 + 18,500 + 18,500) = 51%, achieving the credit. On the other hand, if the non-recyclable waste material consisted instead of 15 cubic yards, weighing 20,000 lbs, the volume calculation turns out to be favorable — (10 + 10) / (10 + 10 + 15) = 57% — while the weight calculation doesn't work out — 1000 lbs of cardboard + 18,550 lbs of concrete / (1000 + 18,500 + 20,000) = 49%. Taking this "logic" to its extreme, if a project's waste calculations, based on recycling a number of different streams — including clean wood — showed that only 49%, or only 74%, of the waste qualified, one could simply order an extra truckload of lumber and immediately transfer it to the recycling bins, thereby reaching the desired threshold for achieving 1 or 2 points under this credit while demonstrating one's commitment to "green" building practices, all for a relatively small cost.

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