Idgi Beyond Interior Design

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1. Beyond Interior Design Interior Design and Global Impacts 2007

Where Design Comes to Life®

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INTERIOR DESIGN AND GLOBAL IMPACTS 2007

1. Beyond Interior Design 2. Indoor Air Quality 3. Materials & Products 4. Selling Green 5. Reference Guide

SPONSORED BY

Where Design Comes to Life® American Society of Interior Designers

Beyond Interior Design Interior Design and Global Impacts 2006

ONE OF FIVE PAPERS ON TOPICS IN SUSTAINABLE DESIGN

Other papers in the series Indoor Air Quality Selling Green Materials and Products Reference Guide

Research/Writing Team Kirsten Childs, ASID, LEED AP Cris Argeles, 7 group Holley Henderson, H2 Ecodesign, LLC Scot Horst, 7 group Nadav Malin, BuildingGreen, Inc. Editors Tristan Roberts and Allyson Wendt, BuildingGreen, Inc. Design and Layout Julia Jandrisits, BuildingGreen, Inc. Graciously sponsored by Lightolier® Steelcase® TOTO® Tricycle VISTA® Wilsonart® Laminate

© 2006 American Society of Interior Designers 608 Massachusetts Ave., NE Washington, DC 20002-6006 www.asid.org All rights reserved. This publication, or parts thereof, may not be reproduced in any form without written permission of the American Society of Interior Designers. Printed in the United States of America.

Table of Contents 1 INTRODUCTION AND OVERVIEW OF KEY CONCEPTS .......... 3 2 THE BASICS OF INTEGRATED DESIGN .................................. 4 Traditional Design .................................................................. 4 Integrated Design ....................................................................5 Integrated Design and Sustainability .....................................7 3 INTEGRATED DESIGN AND THE INTERIOR DESIGNER ......... 9 The Role of the Commercial Interior Designer ..................... 9 The Role of the Residential Interior Designer ...................... 9 The Designer’s Role Beyond Design and Construction ............................................................ 11 4 ENVIRONMENTAL IMPACTS AND SUSTAINABLE DESIGN STRATEGIES ..................................... 11 Natural Resource Depletion .................................................. 11 Energy Use ............................................................................ 15 Pollution ............................................................................... 17 5 INTEGRATED DESIGN AND GREEN BUILDING RATING SYSTEMS .................................................................. 20 ENDNOTES .................................................................................... 21 APPENDIX: QUESTIONNAIRE .................................................... 22

INTRODUCTION AND OVERVIEW OF KEY CONCEPTS

1 Introduction and Overview of Key Concepts Interior design doesn’t exist in a vacuum. It is an integral part of any building construction or renovation project. Building interiors are fitted with materials, products and systems from a network of raw materials that stretches around the globe. And the occupants of those spaces use energy and other resources in ways that are driven, at least in part, by the design of the space itself. Good interior design, and especially sustainable interior design, must be informed by all these interconnections and impacts. Buildings, their supporting infrastructure and their associated maintenance represent an enormous proportion of mankind’s direct and indirect impact upon the environment. Although the total impact of buildings goes far beyond energy use, the construction and operation of residential and commercial buildings consumed 40 percent of the energy1 and 72 percent of electricity produced in the United States in 2003.2 The production of energy from fossil fuels, such as coal, natural gas and oil requires extraction, refinement and transportation, all of which have major environmental impacts. The actual generation of electricity, as well as the combustion or burning of fossil fuels for heat and transportation, result in the release of air pollutants, which cause acid rain, such as sulfur dioxide (SO2), nitrogen dioxide (NO2) and large quantities of the greenhouse gas carbon dioxide (CO2). The United States, with less than five percent of the world’s population, generated approximately 24 percent of the world’s total energy related carbon dioxide emissions in 2002.3 Beyond this enormous consumption of fossil fuels, buildings and their interiors are responsible for widespread depletion of natural resources, including the use of land, raw materials and water. Recent surveys show that rural land is being converted to roads, buildings and industrial uses at the rate of approximately 2.2 million acres per year.4 Nationally, it is estimated that 408 billion gallons of water were withdrawn from natural sources for use during 2000.5 Further, the construction, operation, maintenance and renovation of buildings and interiors generates waste and pollution in many forms, creating local and global changes. Sustainable design is a way of thinking that considers the impact of these issues on the environment and on human health in the context of building and construction. By taking an informed approach to the way design decisions are made, beginning with an understanding of how every choice affects the environment, interior designers can begin to help mitigate these impacts. Interior design is a key aspect of any green building process. It is the design discipline that is most explicitly concerned with how people will experience their built environments and therefore has huge implications for human health, well-being and productivity, all central tenets of sustainable design. Choices made in designing an interior space have environmental and human health implications that extend far beyond the space itself into the neighborhood, region and the whole planet. Sustainable design asks designers to expand their conventional thinking and to focus holistically on the occupants of the homes and other buildings. This approach requires the designer to address issues relating to the health and well-being of occupants, as well as issues of how design choices will affect the environment.

Sustainable Design The practice of designing buildings (and other things) so that they exist in harmony with natural systems. Ideally, the resulting buildings contribute to human and ecosystem health while minimizing harm from their construction and operation.

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Integrated design is a collaborative design process that has two sides: one, the recognition of the interconnectedness of different building systems, and two, extending that same recognition by seeing how professionals who are responsible for different building systems have important information to offer each other. The key to integrated design in a residential or commercial project is communication. Participation early in the project by all team members—preferably before the schematic design phase starts—allows each professional within the team to draw on the expertise of the others in the development of a refined and cohesive design. This early coordination avoids duplication of effort and common errors that result from lack of seeing the big picture. If a knowledgeable team communicates effectively about the sustainability goals, their project is likely to demonstrate excellent environmental characteristics while providing a highquality interior environment. For both the interior space and the building as a whole to perform optimally, interior design cannot be seen as a separate, isolated discipline, but needs to be an integral part of the overall design approach. The interior designer on a residential or a commercial project should be engaged as a key participant from the beginning of the design process, and can contribute to decisions related to site selection, orientation, massing, and mechanical and electrical system design with an understanding of how those choices will affect spaces inside the building. While some aspects of this paper will have direct implications for interior design, the overall goal is to familiarize the interior designer both with broader environmental considerations, as well as with a tool, integrated design, that provides an avenue for full recognition of these considerations in the building process.

2 The Basics of Integrated Design Because of the complexities of different building components and systems, understanding those systems requires specialized knowledge. Specialized roles have therefore been created around the design, construction and maintenance of buildings and interiors. The roles can include those of the architect, interior designer, MEP (mechanical, electrical and plumbing) engineer and general contractor. In a large and complex project, many more roles can exist. Although the design of any building or interior requires the work of all of these professionals, the design process is not traditionally collaborative. A more collaborative process, “integrated design,” will be contrasted with the traditional process to better illustrate opportunities for more environmentally beneficial design.

Traditional Design Traditional design is a linear process in which no team member is fully cognizant of the methodologies and goals of other members. When one member of the project team completes his or her portion of the project, the drawings are handed off to the next member of the team to complete the next portion, and so on down the line.

THE BASICS OF INTEGRATED DESIGN

For example, once the architect has completed the schematic design, the structural engineer “engineers” the building in accordance with the preliminary drawings, then the mechanical engineer designs the building systems within the constraints that resulted from these schematics. Finally, after these key decisions have been made, the interior designer receives the drawings, too late to provide feedback about most aspects of the building’s design. At this stage, it would be both time consuming and expensive to make changes to the baseline documents, so many opportunities to tailor the interior design are lost. The traditional design process is good at producing buildings that achieve conventional performance levels. But if a project’s goals include high-energy performance and exceptional human comfort and health, this process, even when each individual has good intentions, fails to capitalize on opportunities to bridge different areas of expertise. For example, the architect may design a building with large expanses of south-facing windows, which he or she perceives as benefiting the building’s lighting and heating. By the time the MEP engineer sees the design, however, it is too late to add exterior light shelves, which would limit glare and heat gain during the hottest times of day. He or she is forced to engineer a larger system to compensate for the likelihood of enormous heat gain associated with the large southern exposure. Finally, the interior designer may have wanted to specify raised access floors with underfloor air distribution as a strategy for a flexible office layout, but the engineer has already specified a detailed ventilation system using the ceiling plenum for distribution. Nor did the designer have the opportunity to suggest to the architect a different module size for the building’s structural system that might work more efficiently with the client’s existing system’s furniture, and which might have allowed for greater daylighting potential and less wasted interior space. In this traditional approach, in either a commercial or residential project, the architect, engineer, interior designer and the client may never sit down together to discuss and understand the goals of the project. As a result, individual team members typically end up inadvertently working at cross purposes.

Integrated Design Integrated design is a collaborative design process that recognizes the relations among building systems and among the team members that design and install those systems. Integrated design therefore requires participation of all members of a project team in order to optimize the performance of the building and the way in which it is built. The integrated design process, including participation by the interior designer, is already widely recognized in commercial building and renovation projects, and a body of knowledge has grown about its application. These concepts are, with little modification, equally applicable to new homes and residential renovations. An integrated design process often begins with a charrette, a group brainstorming session often taking place over a number of days, which can effectively kick off the project design by providing a forum for articulating goals and sharing ideas. The charrette is an excellent time to bring in the early and active participation of the full design and construction team. Many of these participants are not traditionally included in the early phases of design, but the process is exponentially enhanced with their involvement.

In a traditional design process, a series of plans are handed from one member of the design team to the next, offering few opportunities for collaboration.

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On a commercial project, typical members of an integrated design team include » Architect » Civil engineer » Commissioning authority » Contractor » Cost estimator » Facility manager and/or maintenance staff » Interior designer » Landscape architect » Lighting consultant » MEP engineer » Owner » Specifications writer » Structural engineer » Tenant or occupants (typically a representative) In an integrated design process, all the members of the project team meet together to collaborate from the start of the project.

» Other consultants with special expertise, such as energy modeling, daylight modeling, industrial hygiene or botany experts The contractor or builder is ideally part of the team from the beginning. Generally this is not possible when a competitive bid process is contemplated. However, in a negotiated contract, the contractor is usually selected early and so may be able to participate in the charrette, and the construction manager often is chosen early and can participate. Depending of the scope of a residential project, members of an integrated design team could include » Architect » Contractor or construction manager » Engineers » Homeowner » Interior designer » Landscape architect » Subcontractors

THE BASICS OF INTEGRATED DESIGN

While the MEP engineer can usually undertake the basic commissioning process for a home, energy modeling may be an important consideration for larger houses, and a specialist may be added to the team. When the team is selected and brought together for the first time, perhaps the most important objectives are to understand the basic project goals and to establish a consistent, collaborative process that will support those goals throughout the duration of the project. Working in tandem from the outset enables each team member to question assumptions and to develop coordinated solutions that result in better building designs, wise budgeting and well-documented construction documents. Through the early communication and meetings, everybody’s input and expertise is used to inform the design, rather than allowing one perspective to impose design solutions on the rest of the team. Team members learn from each other and set priorities and goals that allow them to see the whole picture in development, as well as to intervene in a timely manner when the design or objectives seem to be at risk as the design progresses.

Integrated Design and Sustainability When green building features are viewed as simply another step in the design process, or an “add on,” the resulting design often has lower levels of environmental performance and higher cost. If a client wants to reduce energy use, it is far more effective to design for energy conservation from the beginning of a project with, for example, site selection that reduces heating and cooling needs, than to spend a lot of additional money in retroactively insulating the building or reengineering it to use less energy. Many, if not all, of the major design decisions that most affect the sustainable performance of a building are made in the early phases of design. Some early decisions that can have large environmental impacts include site selection, building orientation, fenestration, and shell and glazing choices. With integrated design, the full team of professionals can provide early input relative to the environmental implications of those decisions. For example, if the architect is pursuing a daylighting strategy, the interior designer can contribute layout, lighting and color schemes that complement that strategy. Without early knowledge of the project goals, the designer may have pursued plans that would make the daylighting strategy less effective, which would, in turn, have increased energy needs and decreased occupant satisfaction relative to averages. Another strategy with environmental benefits that calls for an integrated design process is the use of exposed thermal mass. Exposed concrete, brick or stone walls, and roof structures can reduce peak cooling loads, especially when coupled with a night-flushing system that expels the building’s heat and uses the naturally colder nighttime air to cool the mass. Implementing such a strategy requires collaboration among the architect, structural engineer, mechanical engineer and interior designer. Additional members of an integrated design team might include an acoustical engineer, who analyzes and mitigates sound transmission issues caused by hard surfaces, and a lighting designer, who can offer energy efficient lighting considerations.

Energy Modeling A tool used by the design team to determine a building’s potential energy use and to spot opportunities for conservation.

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In an effective integrated design process, “the team works as a collective to understand and develop all as-

Beyond creating collaboration on certain strategies, an integrated design approach benefits environmental goals by facilitating a free exchange of ideas in an open, cross-disciplinary format while respecting the authority of individual experts on a team.

pects of the design. The design can

Examples include

then emerge organically, with the

» Reducing global pollution associated with every phase of building/renovation

full benefit of each expert’s input—a structural engineer can contribute structure, a mechanical engineer can

» Minimizing the development footprint of new buildings and infrastructure

inform choices that enhance energy

» Protecting and enhancing the entire building site

to the elegance and efficiency of the

efficiency and comfort, a landscape architect and civil engineer can

» Fostering local community goodwill and interaction

optimize the siting and orientation,

» Using energy more efficiently

an interior designer can improve the indoor spaces, a contractor can en-

» Using materials more efficiently

hance the constructability of the re-

» Using local and resource-efficient materials

sulting design, and a cost estimator can manage the budget. Depending on the size and complexity of the project, the owner, prospective occupants, facility managers, and a wide range of specialty consultants may be involved as well. While each expert plays an essential role in effective integrated design exercises, the best ideas often emerge when participants cross the usual boundaries, because their views are not as limited by familiarity with the way things are usually done.”6

» Designing durable and flexible buildings for future adaptability » Using water efficiently in buildings and landscape design » Designing interior environments to support well-being and productivity » Minimizing construction and demolition waste By engaging the expertise and inherent wisdom of the entire team at the beginning and throughout the process, sustainable design goals, including energy efficiency and a healthy interior environment, can be optimized more readily.

INTEGRATED DESIGN AND THE INTERIOR DESIGNER

3 Integrated Design and the Interior Designer No matter what kind of project the interior designer is working on, whether commercial or residential, the designer faces a number of constraints, including financial limits and scheduling requirements. The integrated design process can help the designer meet the challenge of incorporating sustainable design into his or her everyday practice on projects of all sizes.

The Role of the Commercial Interior Designer A number of items that are central to the interior designer’s work affect the building’s energy use and system design, including the floor plan, partition design, lighting design and interior finishes. The choice of interior finishes and design can also affect indoor air quality, building maintenance, acoustics and occupant comfort. The integrated design process gives the interior designer the opportunity to discuss how design choices will affect other building systems, and for the designer to adapt to building systems choices made by other team members. For example, in one project meeting, an integrated design team made the connection between the reflectivity of interior paint and the number and type of lighting fixtures necessary for the interior. Because the interior designer guided the team to select a paint color with a high reflectivity, the lighting engineer was able to significantly reduce the number of lighting fixtures needed. As a result, the HVAC engineer was able to reevaluate, and ultimately reduce, the size of the HVAC system. This series of choices—none of which could have been made without the other—led to a higher quality of interior light, reduced energy costs, reduced heat load, and reduced installation and maintenance costs for the HVAC and lighting systems.

The Role of the Residential Interior Designer On smaller residential projects, the kind of integrated design process that is becoming more common with commercial projects may require a larger scale that is out of proportion to the potential benefits. However, even the smallest project, such as a bathroom renovation, can be designed and implemented in a way that reflects concern for occupant comfort and health and for environmental sustainability. Even without a fully integrated team or process, getting all the players—in this case the homeowner, the architect, the contractor (or the plumber) and the interior designer—in one place at one time at the beginning of the design process to discuss the project objectives can contribute significantly to the success of the project. The interior designer often has a unique relationship with the homeowner that can facilitate the exchange of ideas among the team and affect the project’s environmental impact. By being present at early discussions and throughout the project, the interior designer can consistently advocate for the client’s goals. The interior designer can find guidance on key issues, such as providing premium indoor air quality and selecting environmentally friendly materials and products, in the companion ASID Indoor Air Quality and Materials and Products papers.

The residential interior designer can often be a voice for a homeowner’s goals, such as daylighting or good indoor air quality. Photo: Scot Horst

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The following example illustrates how a residential interior designer can use these concepts in an integrated design process to create a more sustainable project: A residential interior designer who had an excellent working relationship with a homeowner introduced the homeowner to concepts of indoor environmental quality and environmentally sustainable design. The homeowner wanted to build an addition to an existing home, and to make a series of upgrades to the kitchen, bathrooms and several other spaces in the existing home. The homeowner worked with the designer to formulate environmental goals and a budget for the project. The main layout was to be determined by an architect friend of the owners, but all other decisions were left to the designer. The contractor had already been chosen by the homeowner and was prepared to coordinate his schedule with the design team and obtain the necessary permits. The interior designer initiated a meeting with the architect, contractor and homeowner to review the homeowner’s environmental goals. These goals included several practices and materials that the contractor had never used before, including a polished concrete floor (instead of tile or stone), FSC-certified woods, rapidly renewable materials, such as bamboo, and some local, sustainably harvested materials. The designer already knew where the contractor could find these materials and subcontractors (such as concrete polishers) that fit the goals of the project, therefore eliminating the potential obstacle of requiring that the contractor research new materials and methods and find new suppliers. The designer gave the contractor ideas about how they might save money on waste by recycling on the jobsite wherever possible, including a program involving coordination with a local waste management company. The designer also pointed out how using certain adhesives, sealants and paints that were all available locally would make a big difference in the indoor environmental quality of the home. Based on the meetings with the project team and the homeowner, the contractor did not oppose using any of these products. Discussions between the designer and the architect focused on layout issues in the bathrooms, kitchen and addition, and served, among other things, to coordinate dimensions shown on the drawings with the standard sizes of the sheet materials to be specified (i.e., 4’ x 8’ and 5’ x 10’) in order to minimize waste. The designer, who was most familiar with the homeowner’s needs, also provided ideas for minor modifications to the architect’s initial plans based on a more comfortable flow of movement in the space. Without this simple integrated process, the architect would not have known how the interior designer’s layout would affect the space requirements. Likewise, the contractor would not have understood how the sustainable goals of the project were actually achievable with little, if any, cost and scheduling impact, and did not represent a challenge to day-to-day business.

INTEGRATED DESIGN AND THE INTERIOR DESIGNER — ENVIRONMENTAL IMPACTS AND SUSTAINABLE DESIGN STRATEGIES

The Designer’s Role Beyond Design and Construction In addition to their key roles during design and construction, both commercial and residential interior designers can play an important role post construction and post occupancy. Interior designers have a unique function in designing the spaces that occupants use daily, and by maintaining a relationship with the owner over time, both the designer and the occupants can benefit. Occupant feedback can provide insight into which sustainable strategies worked well and which were less successful in a project. The designer can use that feedback to improve the design of subsequent projects and to avoid repeating mistakes. Receiving occasional access to a completed project for walk-throughs with potential new clients provides a way of displaying successfully completed work. Prospective clients will benefit by seeing a designer’s work firsthand, as well as seeing the goodwill between the designer and the owner. A successful completed project that embodies environmental and human health features helps demonstrate to everyone involved in the project, and to prospective clients, that sustainable design is simply good design. An office, hospital or home does not have to look or feel different to be an environmentally friendly project. An effective project usually demonstrates, in fact, how sustainable design, with features such as enhanced daylighting, good indoor air quality and thermal comfort, looks and feels better than a conventional project. In this way, successful projects serve to enhance a designer’s reputation and are an effective way to encourage word-of-mouth referrals.

4 Environmental Impacts and Sustainable Design Strategies The construction and operation of buildings and homes has the potential to cause numerous and far-reaching impacts on the environment. This section provides specific strategies that can be used to minimize these impacts— strategies that the designer can use in an integrated design process to meet a client’s environmental and design goals.

Natural Resource Depletion Designing buildings and interiors that conserve natural resources, land, habitat and water has long-term benefits for preserving the environment and the raw material resource base that sustains human activities and, ultimately, all life.

Raw Material Resources As discussed at the beginning of this paper, the energy use by buildings and their need for materials is enormous. However, the designer can use a number of strategies to reduce that burden on our raw material resources.

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The reuse of existing building stock and building elements not only saves large quantities of raw materials, it also preserves architectural and design links to the past. Although in many cases deteriorated buildings need to be demolished, much can be saved when an old building is renovated instead. The shell of the building can be saved, and interior architectural elements, such as walls, floors and ceilings, can be salvaged or refurbished. Decorative elements, such as terra cotta details, rainwater gargoyles, cast iron railings and hand-hewn beams, may be valuable items that can be used creatively to provide a renovation with a sense of the building’s history.

Specifying materials with recycled content, such as the recycled glass countertop shown above, can reduce the use of new materials and lower the environmental impact of a project. Photo: Ice Stone, Inc.

Embodied Energy The energy expended in the process of creating a product, often including the fuel value of its constituent parts.

An Internet search easily yields many used materials exchanges, and the U.S. Environmental Protection Agency provides a listing of some on its Web site: www.epa. gov/jtr/comm/exchange.htm

Other used building materials that can be salvaged are appliances and lighting and plumbing fixtures in good working order. Before using such fixtures, the designer must evaluate these products to ensure that they meet new energy and water consumption efficiency standards. Doors, cabinets and millwork are also readily salvageable. A growing industry of mostly local companies caters to salvaging, refurbishing and reselling many of these elements. Many communities have thriving markets for such items and both nonprofit and for-profit “used building materials” stores exist throughout the country, in addition to the many exchange venues on the Internet. Items can also be donated to organizations, such as Habitat for Humanity® International, Goodwill Industries International® and other nonprofits. On many renovation projects, furniture and furnishings are replaced well before their useful life is up. Rather than automatically assuming that it is necessary to purchase all new items, the designer can evaluate existing furniture for condition, quality and style. In many cases, the designer may determine that it is feasible to reuse furniture “as is” or to refurbish it, while using other elements, such as layout and finishes, to create the new look sought by the client. Reusing furniture and furnishings reduces waste, conserves raw materials and often saves money for the client. Salvaging used materials that would otherwise be landfilled, as well as separating out recyclable building materials during demolition and construction, not only has an environmental benefit but can also save the client from having to pay landfill tipping fees. In 2004 these fees averaged $34.29 per ton nationally, but reached as high as $70.53 per ton in certain regions.7 The use of materials with recycled content such as steel, wallboard, ceiling tile, flooring, carpet, countertops, and tile, reduces the use of raw materials and the underlying energy costs associated with the extraction, transportation and primary processing of virgin materials. Typically, recycling used materials into new products requires significantly less energy than processing raw or virgin materials. The purchase of materials that are harvested or manufactured in close proximity to the project reduces the embodied energy of the materials represented by transportation and energy costs, and also reduces the associated pollution. Although imports have become increasingly prevalent, a small investment of time and effort can often yield the names of designers and manufacturing facilities based regionally and nationally. Products that are made with rapidly renewable materials, such as bamboo, cork or linoleum flooring, cotton and hemp furnishings, wheatstraw cabinetry, and wool carpet and upholstery, are often environmentally preferable to products made from nonrenewable resources. Rapidly renewable materials are those that

ENVIRONMENTAL IMPACTS AND SUSTAINABLE DESIGN STRATEGIES

are replaced in less than 10 years through natural processes, such as annual agriculture cycles or short-term forestry cycles. As noted in the example in the previous section, the designer can use strategies, such as dimensional planning, to get the most out of the materials that are used. By designing room dimensions that respond to standard or modular building products, the designer can significantly reduce waste.

Land and Habitat Conservation While the conversion of natural landscapes for new construction continues side by side with economic expansion, development needs must be balanced with land and habitat conservation to preserve the quality and biodiversity of the natural world. Tipping the scales too heavily and quickly in the direction of development unnecessarily destroys wildlife habitats, reduces diversity, disrupts natural water flows, mars the beauty of the natural landscape, and reduces open space available for recreation and future needs. The informed designer can be an advocate for a client’s needs and for environmental concerns; both can often be met without undue compromise. Instead of assuming that a new building is essential, the designer can help a client find and evaluate spaces suited to the project requirements by investigating existing buildings or undertaking research of the existing local stock of buildings for sale or lease. If a new building is called for, building or renovating in an urban locale with existing infrastructure, such as electrical, water, wastewater and transportation, in place can be significantly less expensive than, and environmentally preferable to, building on an undeveloped site or greenfield. In the case of a housing development, the designer can suggest ways to group the community of buildings to reduce the overall construction footprint, thereby preserving land for the enjoyment of the whole community. Portions of a site with exceptional wildlife habitat, wetlands and or unique natural conditions should be set aside. In addition to identifying areas that need to be protected during building design and construction, and following applicable local and national codes for site selection, several other key precautions will help protect the environment and the inherent natural quality of the site. A carefully designed sediment and erosion plan that is implemented during building construction minimizes the loss of topsoil and prevents soil sedimentation in local water bodies and storm drainage systems. By limiting the extent of the site area that is disturbed during construction and reducing the development footprint—including building footprint, paved driveways and walkways, and access roads—damage to the land and site ecology can generally be minimized and greater biodiversity preserved. “Heat islands” are formed in areas where a large proportion of the natural vegetation is replaced by buildings, pavement and other impervious structures and surfaces. Because these surfaces absorb heat from the sun, they cause localized temperature increases of anywhere from a couple of degrees Fahrenheit to 10 degrees or more when compared to the surrounding undeveloped and naturally vegetated areas. These temperature increases affect wildlife that is sensitive to such changes, with a resultant loss of biodiversity. Buildings that fall within these micro-climate areas require more air conditioning, which uses energy and further pollutes the atmosphere. Strategies, such as installing light-colored or

Urban Heat Island A densely populated area in which pavement and buildings absorb, store and rerelease solar energy, making the immediate vicinity warmer than it would be if the pavement and buildings were not present.

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vegetated green roofs, using maximum amounts of “open-grid” paving and/or light-colored, reflective pavement, along with the planting of shade trees and vegetation, lessens the impact of heat islands and improves the quality of the local environment. As these examples illustrate, an interior designer who integrates environmental values into his or her work need not be bound by the traditional scope of the profession. Issues like the wise use of resources and the preservation of open land are universal, and the integrated team approach to building design and construction empowers any professional to air an opinion or initiate a discussion.

Potable Water Consumption

Green roofs, such as this one in Mashantucket, Conn., can help offset the urban heat island effect and can also help control stormwater runoff. Photo: Green Roofs for Healthy Cities

If the rate of ground water depletion surpasses the rate at which it is replenished—as is currently occurring in many parts of the United States—wells must be drilled deeper and at greater cost to extract the water from subterranean aquifers, often with reduced water quality as a result of salt water intrusion and other types of contamination, and increased risks of land subsidence. Rivers are also being depleted of their natural flow, harming their ecosystems.8 By implementing water conservation strategies throughout building and landscape design, designers draw less of the available supply, help minimize the discharge of effluent and chemically treated water back into the ecosystem, and reduce the costs associated with potable water use, sewage conveyance and treatment fees. Several specific strategies can be used to reduce potable water consumption. These may fall more or less within the traditional scope of the interior designer, but again, the integrated design process offers a more open forum in which environmental issues are treated proactively and holistically. In desert or arid regions, or in those areas with seasonal dry periods, a substantial amount of water is used to irrigate residential landscaping, including lawns, gardens and trees. A xeriscape approach—the careful selection of native or drought-resistant species—allows designers to reduce, and possibly eliminate, long-term water usage for landscape irrigation. When irrigation is called for, high-efficiency systems equipped with slow drip distributors, moisture sensors and timers can decrease waste through runoff and evaporation while increasing irrigation effectiveness. With indoor water use, the Energy Policy Act of 1992 (EPAct) established a national manufacturing standard for plumbing fixtures, such as toilets (1.6 gallons per flush/gpf), urinals (1.0 gpf), showerheads (2.5 gallons per minute/gpm) and faucets (2.5 gpm). Since then, significant advances have been made, and fixtures that are substantially more efficient than required by EPAct are readily available. Recent advances have also made these fixtures, such as low-flow showerheads, more satisfying to use than earlier versions. The specification of water-efficient plumbing fixtures and technologies substantially reduces the potable water used in commercial buildings and houses, which in turn also helps alleviate the burden on municipal water supplies and water treatment plants. It also reduces the use of municipal water conveyance systems—both supply and disposal—thereby helping to avoid the need for new infrastructure and the construction of new treatment facilities.

ENVIRONMENTAL IMPACTS AND SUSTAINABLE DESIGN STRATEGIES

The following provide some basic guidance: » Unlike conventional toilets, dual-flush toilets have two flush options: a full flush (the standard 1.6 gpf or less) for solid wastes and a short/half flush (only uses 0.8 to 1.1 gpf) for liquid wastes. » Waterless urinals look similar to normal urinals and function similarly, but are designed to work without the use of any water for sewage conveyance. These urinals have been widely used for years, particularly in commercial buildings, and have demonstrated no increased odor—a great concern among potential first-time specifiers or users—and are easy and inexpensive for an informed maintenance staff to maintain. » Ultra low-flow showerheads with flow rates of 1.5 gpm are available as both wall-mounted and handheld units. These devices use aerators to enhance the quality of the water flow and maintain wetting efficiency, and compare satisfactorily with conventional high water flow showers. » Individual low-flow faucet aerators can be attached to existing lavatory and kitchen faucets. By retrofitting 1.0 gpm aerators to lavatory faucets and 1.5 gpm aerators to kitchen faucets, water waste from such fixtures can be substantially reduced without affecting performance. Stormwater drainage is another important environmental consideration in sustainable building. Buildings present impervious surfaces, and in dense urban and suburban settings, rainwater cannot return naturally to replenish groundwater sources. Instead it is shunted to stormwater drainage systems, which cause erosion problems, flooding and flushing of hazardous materials into local waterways. By harvesting and storing rainwater, typically in cisterns on the building roof or in the basement, designers can supply much of a building’s nonpotable water needs, such as water for toilet flushing and for landscape irrigation, while mitigating harmful effects of stormwater runoff and reducing potable water consumption. With any non-standard system, the interior designer can play an important role in developing or coordinating signage to guide users. Even in areas where water shortage is not currently an issue, protection of this vital natural resource is a critically important, sustainable objective that often carries associated energy and infrastructure cost savings.

Energy Use The enormous amount of energy consumed by buildings causes environmental harm due to extraction, refinement and transportation of fossil fuels, and air pollution from burning fuels. For example, most coal in the United States is extracted through surface, or strip, mining. This process entails removing large quantities of earth to reveal a coal vein, with mountaintops frequently leveled and valleys filled in. Although federal law requires mining sites to be restored,9 the damage to the original ecosystem is often irreversible. Designing both commercial and residential buildings for high energy efficiency helps reduce these environmental impacts. Computerized energy modeling can be used to guide and optimize the efficiency of the design of the mechanical system and envelope of a building. By creating a virtual energy model early in the process and reviewing multiple optimization

Low-flow faucets often use aerators to improve their performance while saving water. Photo: Kohler, Inc.

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options, designers can reliably achieve a high level of energy efficiency. Similarly, a lighting model allows for the testing of different scenarios to achieve a high quality, energy-efficient lighting scheme. This work is highly specialized, and the designer’s role is to supply data to the modeling engineer, and provide him or her with a variety of system and materials options to consider. This modeling process produces a set of results that include a number of the designer’s options paired with their cost and environmental impacts. The designer and the client then have a basis for making a decision in terms of desired look, building efficiency, environmental impacts and budget, and can select a best scenario that meets project goals. Strategies, such as orienting the building to maximize passive solar heat and light gain, allow for the natural assets of the site to be used to maximum effect. In tandem with a passive solar strategy, the design team can choose glazing options to maximize natural daylighting, while using architectural devices, such as smart glazing and interior light shelves, to control heat gain. Designing a thermally efficient building envelope with high R-value wall and roof insulation and low U-value windows is one of the best strategies for reducing energy use in both hot and cool climates. Heating and cooling systems should then be matched appropriately with building needs to prevent over- or under-sizing systems.

R-Value Measure of resistance to heat flow. The higher the R-value, the lower the heat loss. The inverse of U-factor.

An integrated design approach to lighting can reduce energy consumption from lights by up to 50 percent, as well as cutting cooling costs by reducing heat from light fixtures. Placing maximum levels of light where it is required for tasks while providing lower levels of ambient light in the rest of the space makes for a flexible, energy-efficient lighting plan. Occupancy sensors and dimming controls can be designed and installed for further conservation. A smart combination of task and ambient lighting can also eliminate discomfort associated with glare and over-lit spaces, enhance the readability of computer and television screens, and provide a safely lit environment. Energy Star labeled windows meet certain U.S. Department of Energy and U.S. Environmental Protection Agency energy performance criteria, and can be used as an alternative to, or replacements for, typical single- and double-glazed residential windows. Additionally, since 1993, new windows have energy efficiency labels from the National Fenestration Rating Council (NFRC). The NFRC labels include an objective performance rating for U-factor and Solar Heat Gain Coefficient (SHGC) for the particular window, which allows consumers to compare similar window products. High-performance windows, with smart glazing and thermal breaks, generate substantial savings through reduced heating and cooling needs for homes. An Energy Star rating for office equipment, such as computers, computer monitors, televisions, copiers, and appliances, such as dishwashers, refrigerators and washers, denotes products that are more energy efficient than average. Also, EnergyGuide labels, required by the Federal Trade Commission to be displayed on certain appliances, can be used to compare the energy use of a particular appliance to similar products. In both cases, reduced energy use has direct benefits, as well as indirect benefits, such as reduced cooling needs and reduced pollution. Renewable, site-generated energy offers an excellent option for reducing fossil fuel use and adding more sustainable options to the nation’s energy infrastructure. Rooftop photovoltaic (PV) arrays and building integrated PV (BIPV)

ENVIRONMENTAL IMPACTS AND SUSTAINABLE DESIGN STRATEGIES

systems, which generate electricity from the sun’s energy, are becoming more affordable in many states. In remote areas where there is no power grid, they can be the sole source of power. In places where the power grid is available, a lowercost system can be installed by tying it into the grid and selling power back to the local utility in what is called a grid intertie system. Private and public grants are available to offset the first cost of such systems and can usually be found by contacting a local utility. Solar thermal energy is also used throughout the United States to heat domestic hot water and pool water. These are practical, efficient and successful applications for solar energy and should be used wherever conditions permit.

Pollution Contamination of the environment from building-related processes is a massive problem and a complex one because earth, water and air all interact with each other, potentially compounding pollution or causing it to appear far from its source. For example, air pollution from smokestacks can be washed into the soil after a rainstorm and subsequently introduced into groundwater sources. Therefore, everyone involved in building design and construction should take a holistic approach to all decisions, remaining aware of both the local and the global impacts of all decisions in terms of their effect on soil, water and air pollution.

Soil Pollution Landfills remain the primary means for the disposal of waste. Although landfill sites must conform to federal regulations, it is not uncommon for contaminated materials and liquids to escape the barriers of a landfill and leach into surrounding soils.10 This soil pollution in turn spreads to groundwater, affecting streams, lakes and wells as the contaminant is distributed through the constant movement of underground water. Incinerating solid waste, another common option, does not avoid these problems. In addition to the air pollution produced, ash, usually containing the same toxic wastes contained in the solid waste, but often in a more leachable form, still remains to be disposed of, usually in landfills. Careful management of demolition and construction waste can minimize the burden on landfill sites and ensure that hazardous materials including mercury, asbestos, polychlorinated biphenyl (PCB) containing materials, and lead paint, are sent to appropriate facilities. The interior designer can help minimize soil pollution by reusing materials and specifying nontoxic materials.

Water Pollution The National Water Quality Inventory 2000 Report to Congress reports that of the water bodies assessed, 40 percent of streams, 45 percent of lakes and 50 percent of estuaries were unclean for human activities, such as swimming and fishing.11 Contaminants introduced into water bodies by precipitation and runoff from urban and agricultural lands represent the leading cause of water pollution. Commonly referred to as nonpoint source (NPS) pollution, it is distinguished from pollution that originates from concentrated sources, such as sewage treat-

Solar heat gain coefficient (SHGC) The fraction of solar gain admitted through a window, expressed as a number between 0 and 1.

For more information on Energy Star, visit www.energystar.gov/windows.

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ment plants or industrial complexes. Although sediment, fertilizers and pesticides from agricultural lands are the most common NPS pollutants, stormwater runoff resulting from urban development and hydrocarbon use (e.g., dripping oil or spilled gasoline from vehicles, or unburnt fuel from two-cycle engines, such as lawnmowers and snowblowers) has become an increasingly large source of water pollution. Limiting the total area of impervious surfaces, such as asphalt and concrete, on a project site, and maximizing vegetated areas reduces the amount of stormwater runoff and associated pollutants. These approaches also slow the rate of runoff, allowing natural bioremediation to occur. Strategies that reduce impervious surfaces include designing smaller parking areas, driveways and sidewalks, or using widely available permeable materials as a substitute. Vegetated swales or planted buffer zones instead of concrete curbs help mediate stormwater, as do pipes directing such water to stormwater drainage systems. As discussed in the previous section on potable water use, collecting and using stormwater for uses such as irrigation also reduces the environmental burden of runoff. Since the most significant sources of point source water pollution are factories and power plants, most residential and commercial design projects are not sources of this type of pollution. However, most buildings use electricity generated at these plants and are therefore implicated.

Nonpoint Source Pollution Water pollution from natural precipitation that runs along the surface of the land and eventually transports any contaminants it encounters to receiving water bodies.

Mercury is a heavy metal and a persistent organic pollutant (POP) originating from the smoke stacks and flues of coal-fired power generation facilities, mining runoff and other sources. It is also still used in manufacturing processes involved in the production of building and interior materials, specifically as an essential ingredient in fluorescent lamp manufacturing and as a stabilizer in some plastics. In 2000, mercury was identified as a major pollutant in lakes and estuaries in parts of the United States.12 While cleaning up the sources of mercury pollution and improving manufacturing requirements are of vital importance, buildings can reduce their responsibility for this type of pollution by designing for energy efficiency and decreasing materials demands. For example, the manufacture of one square yard of carpet typically requires the use of approximately 8.9 gallons of water13, primarily for dyeing the yarn and washing to eliminate excess dye. Most of that water ends up as treated discharge wastewater, or effluent. While the carpet industry tries to ensure such water meets state and federal regulations for pollutant levels before it is returned to any receiving body, interior designers can mitigate this water use and potential pollution issue by specifying solution-dyed carpet products, which use minimal, if any, water in their manufacturing process.

Global Atmospheric Pollution Stationary sources of air pollution include industrial plants, manufacturing plants, steel mills, power plants and waste incinerators, to mention a few. While these sources are stationary, their effluent and the smoke, gases and particulates discharged from their stacks and chimneys have wide distribution via groundwater and air currents. Among the major global atmospheric pollutants, sulfur dioxide (SO2) is primarily emitted from power generation plants, petroleum refineries, steel mills and fertilizer manufacturers. Nitrogen oxides (NO2) are emitted in great quantities from electrical utilities and industrial boilers. These two chemicals are the main contributors to acid rain, which is destroying forests in

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Europe and both South and North America. As noted above, these facilities also generate mercury emissions and carbon dioxide (CO2), a major greenhouse gas. By using resource-efficient building practices, including those discussed in this paper, designers and builders can help minimize the demand for new manufactured products from factories that contribute to air pollution. Designing energy-efficient buildings and interiors helps alleviate dependence on industrially produced power. Although the impact of any one building is small in relation to overall energy use, when these practices become commonplace, the impact of thousands of sustainably designed, energy-efficient buildings will result in significant energy savings and greatly reduced air pollution. Siting commercial buildings and residential communities in close proximity to mass transit terminals, encouraging carpools and vanpools, and promoting bicycle use encourages sustainable transportation options. Sidewalks and paths for pedestrian movement, well equipped with amenities, such as benches, shade trees and waste receptacles, further encourages a reduction in vehicular use, especially at the local level, where maintaining high-quality air is essential for the well-being of the community.

The chart above shows the flows of energy, in watts per square meter (W/m2), between space, the atmosphere and the earth’s surface. Human activities have increased the concentrations of greenhouse gases in the atmosphere, thus contributing to global warming.

Building design and construction also has an impact on other major sources of air pollution, including gas combustion engines in cars, trucks, boats and lawnmowers. Burning fossil fuels to power these vehicles releases greenhouse gases, particulates, nitrogen oxides, and VOCs, which contribute to the formation of ground-level ozone (O3) or smog, resulting in increased respiratory illness, such as asthma.

Illustration: Global Warming Art

Planting native or wildflower meadows instead of monoculture grass lawns reduces the need to use lawnmowers and trimmers, at the same time eliminating the need for fertilizers, herbicides and pesticides, which spread across millions of acres of American lawns, are major consumers of petroleum, and are serious contributors to water pollution and resultant disruption of aquatic ecosystems. Indigenous species are also well acclimatized to the seasonal rhythms of the region and, used in well-designed landscaping, do not need to be excessively watered.

Greenhouse Gas Emissions The greenhouse effect results when gases in the atmosphere absorb radiation from the earth’s surface, trapping heat in the atmosphere. Human activities, including industrial and manufacturing processes and transportation, have dramatically increased atmospheric concentrations of these greenhouse gases, including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), thereby contributing to global warming.14 There are many ways to reduce the release of greenhouse gases from building-related construction, operations and maintenance. As we have discussed throughout this paper, buildings should be designed to be as energy efficient as possible and to use renewable energy sources. Most electricity is generated by burning fossil fuels, such as coal and oil, which release greenhouse gases in addition to other pollutants.

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A number of regional utilities offer ways to purchase renewable energy, and other programs, such as green tags, renewable energy certificates (REC) and tradable renewable certificates (TRC) are available on a national basis.15 Because landfills produce almost one-third of the national emissions of methane,16 minimizing landfill usage by diverting waste through salvage, reuse and recycling programs ultimately reduces methane emissions. Methane is a major greenhouse gas that has 21 times greater potential than carbon dioxide to trap heat in the atmosphere. Carbon dioxide emissions from vehicles running on gasoline currently accounts for nearly one-third of energy-related greenhouse gas emissions in the United States.17 Strategies described previously to reduce single-occupancy vehicle commuting present an important opportunity to slow global warming. The interior designer can support this effort by designing useful facilities for bicycle storage and showering.

Light Pollution

North America is outlined with dots of light when seen from space at night. Poorly designed exterior lighting can contribute to light pollution, which can disrupt nocturnal habitats and reduce night-sky views. Photo: Craig Mayhew and Robert Simmon, NASA GSFC.

Night-time illumination for outdoor areas provides safety for pedestrians and motorists. However, poorly designed exterior or landscaping lighting schemes cause glare and may result in light spill into neighboring homes and properties, reducing night-sky views, wasting energy and disrupting local nocturnal habitats. By eliminating any type of lighting directed upward, specifying shielded outdoor fixtures and avoiding excessively bright luminaries, the impact of light pollution can be mitigated.18 Interior designers can help ensure that any indoor lamps are designed to minimize the amount of light that escapes into the night sky through windows or skylights.

5 Integrated Design and Green Building Rating Systems Using an integrated design process along with a green building rating system, such as LEED® and the National Association of Home Builders (NAHB) Model Green Home Building Guidelines, can improve building design by including concern for environmental impacts during the design process, in addition to aesthetics, function, durability, maintenance and cost. Rating systems (which are covered in greater details in other ASID white papers in this series) provide ideas for a number of key environmental considerations that can be incorporated into the overall design approach, no matter the size of the project. A green building rating system is often used during the team meeting at the beginning of the project, to guide discussion and help the team consider ecological, sustainability and health factors in a comprehensive manner. The rating system can also be used throughout the integrated design process, whether the project is commercial or residential, to direct discussion, encourage collaboration, and generally support the process of creating a sustainable building.

INTEGRATED DESIGN AND GREEN BUILDING RATING SYSTEMS — ENDNOTES

In some situations, the use of a rating system can also have the unfortunate effect of encouraging the design team to focus narrowly on individual points or measures that appear easiest to achieve rather than on the measures that will result in the best overall building. To minimize this tendency, conversations within the design team from the project’s inception should use the rating system primarily as a springboard from which to explore the owner’s values and the best environmental solutions for expressing those values. Only once the basic values have been clarified and the design direction established should the team concentrate on the requirements for achieving specific points. As discussed throughout this paper, an integrated design approach is an excellent way to coordinate and develop the sustainable qualities of a project. The process can contribute to reduced environmental impacts at the global, regional and local levels, while promoting high building performance and an enhanced quality of life for all occupants and users.

For additional details, visit the USGBC Web site at www.usgbc.org.

For additional details, visit the NAHB Web site at www.nahbrc.org/greenguidelines.

Endnotes 1. Buildings Energy Data Book: 1.1 Building Sector Energy Consumption, U.S. Department of Energy, http://buildingsdatabook.eere.energy.gov/docs/ 1.1.3.pdf, August 2005. 2. Buildings Energy Data Book: 1.1 Building Sector Energy Consumption, U.S. Department of Energy, http://buildingsdatabook.eere.energy.gov/docs/ 1.1.6.pdf, August 2005. 3. “Emissions of Greenhouse Gases in the United States 2004,” Energy Information Administration, U.S. Department of Energy, DOE/EIA-0573 2004.

9. Surface Mining Control and Reclamation Act, 30 U.S.C. 25 10. 40 CFR Part 258 (Subtitle D of RCRA). 11. National Water Quality Inventory: 2000 Report, U.S. Environmental Protection Agency, Office of Water, EPA-841-R-02-001, August 2002. 12. National Water Quality Inventory: 2000 Report, U.S. Environmental Protection Agency, Office of Water, EPA-841-R-02-001, August 2002. 13. The Carpet Industry’s Sustainability Report 2003, The Carpet and Rug Institute (CRI), 2004.

4. National Resources Inventory 2001 Annual NRI: Urbanization and Development of Rural Land, Natural Resources Conservation Service, July 2003; Hutson et al., Estimated Use of Water in the United States in 2000, USGS Circular 1268, United States Geological Survey, February 2005.

14. Inventory of U.S. Greenhouse Emissions and Sinks: 1990-2000, U.S. Environmental Protection Agency, EPA 430-R-02-003, April 2002.

5. Hutson et al., Estimated Use of Water in the United States in 2000, USGS Circular 1268, United States Geological Survey, February 2005.

16. Inventory of U.S. Greenhouse Emissions and Sinks: 1990-2000, U.S. Environmental Protection Agency, EPA 430-R-02-003, April 2002.

6. “Integrated Design,” Environmental Building News, Vol. 13, No. 11, November 2004.

17. Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2003, U.S. Environmental Protection Agency, EPA 430-R-05-003, April 15, 2005.

7. Edward W. Repa, NSWMA’s 2005 Tip Fee Survey, NSWMA Research Bulletin 05-3, March 2005.

18. IESNA Recommended Practice Manual: Lighting for Exterior Environments (IESNA RP-33-99), Illuminating Engineering Society of North America, 1999.

8. “Ground-Water Depletion Across the Nation,” U.S. Geological Survey Fact Sheet 103-03, USGS, November 2003.

15. http://www.eere.energy.gov/greenpower/markets/certificates. shtml?page=0.

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Appendix: Questionnaire The following questions are offered for the benefit of the reader to evaluate whether the learning objectives of the paper have been achieved:

1. What are some differences between traditional design processes and integrated design processes?

2. What are the fundamental goals of any sustainable design process? How are these achieved?

3. Explain how both a commercial and a residential interior designer can be involved in the integrated design process. Discuss this new expanded role for the interior designer and what it means.

4. What could be considered the primary strategy in reducing natural materials depletion during construction and fit-out?

5. Name three strategies for reducing potable water consumption of a building.

6. Explain how reducing construction waste destined for landfills affects global warming. What strategies can be employed?

7. Provide five examples of energy efficient strategies that can be implemented throughout a building.

8. How is the environment positively affected by the use of human-powered transport?

9. How can the selection of a building site—whether commercial or residential—affect the environment? Name four sustainable approaches to selecting a site.

10. Explain how greenhouse gases can contribute to global warming, and list some examples of these gases.