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How Building Codes Affect Sustainable Development |
Building codes are one of the main barriers that remain to wide-spread implementation of alternative building materials by excluding nontraditional materials, limiting their use or allowing only experimental building systems. Six "green" building experts offer their perspectives. |
by Nicole Capretz
TABLE OF CONTENTS
Buildings have an enormous impact on the environment, consuming up to one half of the world's physical resources.(i) Much of this impact occurs during construction, particularly in the production and transportation of building materials. Worldwatch Institute estimates that a few months of building construction can consume more resources and generate more pollution than a decade of building operation.(ii) Wood is the primary material used in homes and small structures in North America. More than one quarter of the world's consumption of wood is used in products such as lumber, plywood, veneer, and particleboard.(iii) The ecological damage from construction-- deforestation, global climate change, destroyed farmland and wildlife habitat, polluted air and water-- in connection with the broader yet interrelated problems of unhealthy indoor air quality, urban sprawl, poor land use planning and automobile dependence have made low-impact, energy-efficient design and construction an appealing solution. Building must be analyzed in a broader context, recognizing and accounting for the people and the community affected by the built environment. Many barriers remain to modernizing the building industry, not the least of which are building codes. Building codes are legal documents designed to "protect public health, safety and general welfare as they relate to the construction and occupancy of buildings and structures."(iv) They regulate construction by specifying minimum building requirements, focusing primarily on building, plumbing, fire safety, electrical systems and heating and air conditioning.(v) Most areas in the country require compliance with one of the three model building codes: the Uniform Building Code, the National Building Code and the Standard Building Code. The three codes are similar, but are tailored for the different regional conditions.(vi) States, counties and cities selectively apply one of the model codes, either as written or with amendments. All codes are enforced at the local level. The model codes are generally printed in new editions every third year, with amendments published during the intervening two years.(vii) Any person or organization may submit a proposal for a change in the model code, which is then reviewed in annual public hearings and voted on by the group's membership. As they exist today, building codes hinder the development of alternative design and construction. They either completely exclude nontraditional materials, limit their use through narrow and restrictive criteria or allow only experimental building systems. For example, the Uniform Building Code used in the western United States recognizes adobe as a building material, but confines its regulation to four paragraphs (the Uniform Building Code has three volumes and a total of 2,749 pages).(viii) In addition, all three codes have sections which allow building officials to approve trial designs and materials, but receiving that approval can be a long and arduous process. The present codes rely on a few standardized, industrial materials such as timber, steel and concrete because they were once viewed as inexhaustible resources which protect the health and safety of individuals in and around buildings. What the codes do not protect is the broader health and safety of the public jeopardized by these resource-intensive building systems. The codes do not pay attention to the environmental and public health implications of how these materials are acquired, distributed and disposed. In this way, low-tech, low-impact designs have a difficult time breaking into the mainstream and receiving code approval.
In 1994, the three model code organizations created the International Code Council (ICC) to oversee the production of a single national building code. Called the International Building Code (IBC), the working draft is now being circulated for public comment and review. The IBC is significant in that it allows any material and method to be used as long as certain performance objectives are met. These objectives can be proven through testing, modeling, calculations or similar means. The IBC also allows compliance using a combination or performance and prescriptive designs, or just prescriptive approaches. This represents a fundamental shift from the current codes, which shut out new materials and designs through strict prescriptive requirements. In addition, the code organizations formed the Conference of American Building Officials (CABO) to develop a National Evaluation Service for testing and certifying building materials and systems.(ix) Many are hopeful that this certification process together with the new model code will help obtain mainstream acceptance for new building systems and set the stage for developing prescriptive standards for these new designs.(x) However, even if the IBC and the certification process help open the door for alternative building systems, there are still many existing barriers. The obvious obstacles include the resistance to change in a competitive and fractured industry and the aforementioned failure of the codes to examine the ecological, health and economic ramifications of building. Perhaps more serious is the lack of awareness and knowledge about green building among the primary users of the code-- building officials, builders, architects, engineers and developers. An organized and sophisticated campaign to educate these key players is critical to breaking green building out of the niche market. The highly organized and well funded resource industries are ready to battle over code acceptance of particular products and methods of construction. Trade associations and industry representatives play critical roles in the code-making process by testifying at hearings, supplying technical information, and lobbying code change committee members outside of public hearings. The National Association of Home Builders (NAHB) reports that average participation at annual public model code hearings between 1977 and 1981 included 67 percent building officials, 17 percent trade associations and manufacturers, and a mere four percent engineers, architects, builders and code consultants.(xi) There is a great opportunity for green building proponents to participate in the code-making process and to influence code policy. Public hearings are occurring in preparation for the 2000 publishing date for the IBC. There will also be future opportunities when the IBC is updated. Furthermore, the local level holds great promise for regional codes, because building officials are sensitive to community interests and economics. While unprecedented opportunities exist for builders concerned about the environment, there will need to be major outreach, education and lobbying efforts to truly direct the industry onto a more sustainable path.
In order to gain an understanding of the impact building codes have on the built environment, the author interviewed the following green building proponents. Ranging from builders to building officials to journalists, each person presents a unique perspective on the role of building codes in sustainable building. BOB FOWLER is a long-time building official for the City of Pasadena, California and a former Chairman of the Board of the International Conference of Building Code Officials (ICBO). The ICBO publishes the Uniform Building Codes, which are used throughout the west. He is one of the co-founders of the International Code Council, which is an organization of code representatives created to develop a single model code system for the United States, the International Building Code (IBC), by the year 2000. Fowler is now working on a proposal to incorporate a chapter in the IBC on alternative building systems. DAVID EISENBERG is the Executive Director of the Development Center for Appropriate Technology (DCAT), an internationally recognized and award-winning non-profit organization which helps develop energy-efficient and low-impact affordable housing. DCAT has played a major role in the development and advancement of straw bale construction, including research and testing activities, demonstration projects and building code development. The center was instrumental in the adoption of the nation's first municipal strawbale building code for Tucson and Pima County, Arizona, as well as the model strawbale construction guidelines in California. David Eisenberg also wrote a manual for gaining building code approval for strawbale structures called, "Straw Bale Construction and the Building Codes." PLINY FISK, III is the Co-Founder and Co-Director of the non-profit Center for Maximum Potential Building Systems (Max's Pot), established in 1975. The Center is a nationally acclaimed sustainable planning, design and development organization based in Austin, Texas. Pliny's expertise is in the areas of sustainable design and building practices, regionally derived building materials and appropriate technologies. Pliny's current and recent activities include being the Principal Investigator of a Cooperative Agreement with the U.S. Environmental Protection Agency to establish regional benchmarks for sustainable building in the United States; a national team member under the U.S. Department of Energy's "Build America Initiative" to develop strategies to enhance the energy efficiency and environmental qualities of industrialized housing; Co-Chair of the American Institute of Architects' Environmental Resource Guide committee; and member of the President's Council on Sustainable Development "Making It Work" Task Force on Sustainable Communities. NADER KHALILI is an award-winning architect, author, United Nations consultant and NASA contributor who is the founder and director of the California Institute of Earth Art and Architecture (Cal-Earth) in Hesperia, California. Cal-Earth Institute is a non-profit educational foundation that sponsors research, project design and apprenticeship programs. Khalili has written three books: Racing Alone, Ceramic Houses and Earth Architecture, and Sidewalks on the Moon, which describe his quest to develop sustainable building techniques. Cal-Earth is currently constructing the world's first totally earth-constructed museum and nature center complex in a high seismic zone. The facility received building code approval in 1993 after three years of extensive engineering tests and skepticism from local building officials in consultation with ICBO (International Conference of Building Code Officials). Cal-Earth hopes to incorporate these earth building principles into local and national building codes. NADAV MALIN is co-editor of Environmental Building News: The Newsletter on Environmentally Responsible Design and Construction. Malin also leads design consulting work for the company. He lectures widely and has written dozens of technical articles on material selection and other design issues relating to green building. He is also helping to coordinate the design and construction of the Northeast Sustainability Center, a state-of-the-art demonstration office building in Greenfield, Massachusetts, that is home to the Northeast Sustainable Energy Association. Before joining the team that started Environmental Building News he was a builder in southern Vermont. Published since July 1992, Environmental Building News (EBN) is a newsletter on environmentally responsible design and construction. EBN is read by several thousand architects and builders throughout the United States and Canada and is widely regarded as the leading newsletter in this field. EBN covers a broad range of issues relating to green building: everything from energy efficiency and water conservation to recycled-content materials, indoor air quality issues and waste reduction. LYNN SIMON is Program Director of Global Green USA's Resource Efficiency/Sustainable Communities program area and is helping to initiate GG USA's "Greening Affordable Housing Initiative." Lynn is also President of Simon & Associates, an environmental building consulting firm based in San Francisco. The firm consults to design firms, non-profit organizations and corporations on a broad range of issues including resource efficiency, sustainable materials selection and healthy building practices. Lynn lectures on green building resources and case studies, and provides environmental education programs and activities for the architectural community and other building industry professionals. She is founder and past chair of the AIA San Francisco Task Force on the Environment, and is currently on the SFAIA Board of Directors. BOB FOWLER
RCA: Why is the International Building Code (IBC) being
developed? RCA: Why is the code called "international" if it is only national in
scope? RCA: Is the IBC performance based or prescriptive? This will open the door for new materials and construction and
allow them to attempt innovative design strategies. Then, base testing
can be done to establish industry-accepted criteria so that builders
would not have to conduct expensive and time-consuming tests every time
they use the same design. (This would be similar to what is done with
the performance-based sections of the codes today for structural
members. A builder demonstrates through engineering calculations that a
structural design will meet the established load-bearing criteria, and
the building official approves the design, for the most part, regardless
of the type of material used). Eventually, prescriptive provisions can
be developed for the new technologies. The average builder feels more
comfortable having a cookbook that tells him/her exactly how to build a
structure, and it eliminates risk and liability.
RCA: What are the disadvantages to performance-based criteria? However, the benefits to allowing performance-based design far
outweigh the hazards. For example, think about brakes for an
automobile. One way is to create a model braking system and develop a
manual that tells a designer/engineer exactly how to replicate the
model. Yes, the car would stop and the designer/engineer would have
little liability for the brake design, but braking technology would never
advance because they would all be the same design. On the other hand,
the performance-based code would say that the objective is to stop the
auto at a certain speed, in a certain distance and on a certain road
condition. Independent thinkers would then have the opportunity to
develop new, improved systems. Similarly, when you encourage builders to
challenge accepted building designs, you may be hitting upon the next
revolutionary building technology. At the least, you will help diversify
available building strategies and avoid an unhealthy reliance on any one
resource. Ultimately, prescriptive codes will catch up and incorporate
the new technology.
RCA: How will the IBC differ from the paragraph in the UBC allowing
performance-based design? How will it further encourage alternative
building sytems? RCA: What is the likelihood of IBC adopting the codes as they are in
their draft form, performance-based? RCA: What made you interested in alternative design and
construction? RCA: Do any other countries have performance-based codes? RCA: What do you see as the barriers to the adoption of alternative
building systems? RCA: How big an influence do the timber, concrete and steel companies
have on building codes? Fortunately, it is difficult to object to performance-based codes
because they do not eliminate the use of the traditional systems.
Prescriptive codes get you into a more narrow mindframe and limit the
types of building designs that are possible.
RCA: Given your years of experience, do you have any suggestions for
how to infiltrate the process? RCA: Why do you believe the sustainable building community needs a
building codes summit? DAVID EISENBERG
RCA: What has been your experience with building codes? Have they
affected your ability to design sustainable buildings? This system makes it nearly impossible to build low-cost,
environmentally appropriate buildings. The process of obtaining a
permit can be a lengthy, arduous and frustrating, unless there has
already been an alternative code approved by local building
officials. And finding capital or insurance can be even worse.
Financial institutions and insurance agencies that supply the
necessary funds and liability protection are influenced by the
regulatory authorities, so that codes can prevent a potential owner
from receiving the capital and protection with which to build.
At DCAT (Development Center for Appropriate Technology), we believe
we have an obligation to reinvent the building codes so that the
health and safety of both the individual and the environment can be
protected. We also acknowledge, however, that preserving capital
investment in buildings and keeping limited liability exposure for
designers, engineers, manufacturers, suppliers, builders and owners
are important and legitimate goals.
RCA: Do you see performance-based codes as the solution? What are
the disadvantages? For example, in the strawbale code we helped develop for the City of
Tucson and Pima County, Arizona, we set minimum prescriptive
standards for bale quality and established some limitations on design
which allows simple, moderately sized single story buildings to be
built without the need for engineering and professional design.
Similarly, California adopted guidelines based on the Arizona code,
but added prescriptive criteria for seismic and climate requirements.
RCA: Is it feasible to develop performance- and prescriptive- based
codes? Who is going to be able to fund the testing needed for codes
to be developed for the many alternative systems? Financial support for the testing of non-proprietary or
non-industrial building materials and systems has been very hard to
come by. This has been a major obstacle to the development of many
low-impact building materials. We are hoping to be able to convince
the insurance industry
that it is in their own best interest to fund the research, testing,
and development program, since these materials offer very large
potential reductions in green house gas emissions. The investment
would be relatively small compared to the benefit. And we're seeking
the support of other institutions and organizations for this work.
RCA: How do you think the proposed performance-based IBC will
change the building market?Is it the green light to green building that
many have been waiting for? RCA: What will be the role of local codes once the IBC comes into
effect? RCA: What do you see as the biggest barriers to the acceptance of
alternative building systems
in the mainstream? RCA: What do you see as the main goal of the proposed building codes
summit? Why will the summit be necessary if the IBC is going to be
performance-based and therefore allow alternative construction and
design? PLINY FISK, III
RCA: What has your experience been with building codes? Have they
affected your ability to design sustainable buildings? Codes developed for health and safety reasons because of fairly
horrible conditions in housing, in particular. The codes were aimed at
protecting the health and welfare of the building occupants, and they
basically slapped down laws for people to obey. Codes began to get
complicated because they started regulating every aspect of
construction. The disappointing part was that each code developed its
own language and it became difficult for those involved in the building
process to absorb the complexity. Part of this complexity evolved from
the manufacturers, who lobbied extensively for focused, narrowly tailored
code provisions that favored their products. It became a
self-reinforcing phenomena. Now it is difficult to remember what the
codes are about. Whose health is the code protecting? The health of the
planet or the individual?
RCA: What do you see as the solution to the "self-reinforcing
phenomena" of the codes? In this way, codes can look at buildings as flexible, living
systems that can be reconfigured and reused. We should be talking about
whole systems integration and cycles vs. end-use, linear solutions. Even
some environmentalists are guilty of wanting "buildings that last seven
generations," without analyzing the ramifications of that structure on
the local community and planet, or whether the building can serve in more
than one function.
An example of products which use this philosophy are specialized
automobiles in Europe. These vehicles are made so that they can be a
pickup truck for one trip and then convert into a van or family car for
the next. These cars also have recyclable components. So instead of
just demolishing the car and wasting the raw material, the cars can be
dismantled and the components resold and reused. Likewise, in buildings
the only thing that should be permanent is the outside structure.
Instead of creating complex and entangled utility lines that force a
building into functioning in only its original purpose, you can simplify
these systems and allow utilities (and hence walls) to be unhinged and
replaced. This is going on in Japan and the Netherlands. The walls are
thick and satisfying aesthetically, and they look permanent, but they are
actually designed to be reconfigured when the purpose of the building
changes.
RCA: How do you think the proposed performance-based IBC will change
the building market?
Is it the green light to green building that many have been waiting
for? RCA: What will be the role of local codes once the IBC comes into
effect? RCA: How can we streamline the approval process under
performance-based codes (which requires lengthy and expensive testing
for each new system)? Are regional prescriptive codes the answer? RCA: What do you see as the biggest barriers to the adoption of
alternative building systems? RCA: What do you see as the role of the summit in advancing green
building? Why do we still need to meet if the IBC will allow for
alternative design? NADER KHALILI
RCA: Why is it important to change current building codes? Further, building codes are essentially written by and for
lumber, cement and steel companies because they are the ones who have the
financial and institutional ability to conduct the necessary research and
testing on products and construction designs to satisfy building code
officials. These conventional systems also have an established source
and language so that code officials feel comfortable adopting these
systems. The problem is that while these manufacturers are usually
reliable for giving data on structural and weather (fire, earthquake,
etc.) characteristics of their materials and techniques, they do not
calculate the external, larger environmental costs.
RCA: Should we replace codes or amend them? At what level --
national and/or local? RCA: Why is it important for building codes to address issues other
than specifying how to design and construct buildings? RCA: Should the new sustainable codes include all alternative
building systems, or just some? I also believe that performance-based codes will reinstate
innovation, acclaim and accountability to builders. By handing over
the construction process to banks, insurance companies and building
agencies, we have lost that pioneering, imaginative spirit of the
first American homebuilders. When we want to build a house we go
immediately to the bank and say, "please, can you give me some money
for concrete, lumber, fittings? Then to the building department,
"please, may I build my bathroom here?" and to the insurance company
we say, "our little stick house will burn down and all our mortgage
payments will come to nothing! Please, can we pay you to take this
risk for us?" This reality stifles originality and eliminates
responsibility.
In addition, I believe people should be able to build their own
house without feeling required to hire an architect/engineer/designer
and go through the labyrinth of regulatory, financial and insurance
requirements. Performance-based codes allow for individuals and
small builders to design and construct their own homes, which are
often less expensive and more labor-friendly.
RCA: How can performance-based sustainable codes be written so that
they don't require testing each time a new building is constructed? In addition, once the building codes allow alternative construction,
finance and insurance agencies will be confident about investing in
these buildings, and companies will be empowered to develop an
infrastructure to invest in further development. This will allow the
new technologies to advance and mature.
The fear is that alternative building will put people in traditional
industries out of work. It is the same type of fear that existed
when computers first entered the market. People were afraid
computers would take over their jobs, when in reality burgeoning
technologies have created more economic possibilities. Similarly,
new building techniques will stimulate economic development because
they are diversifying the mix of building practices and expanding the
industrial markets. It is not efficient or effective to rely on any
one building technology, just like it is not practical to rely on
nonrenewable energy sources such as coal and oil to meet all of our
energy needs. The only thing we need to ensure is that new
technologies are not compared to established products and designs.
For example, a piece of adobe cannot be compared to a concrete block
because even though they may be used for the same purpose, they are
two entirely different materials. A concrete block is obviously
stronger than an adobe brick, but that is often not a concern because
you don't always need the strength of a concrete block to accomplish
your goal. It is like comparing a bicycle to a car. Both
are viable transportation methods, but comparing their speed does not
demonstrate where each technology is appropriate.
RCA: What do you see as the greatest barriers to the adoption of
alternative construction? RCA: How do you think insurance agencies and banking groups will
respond to changing codes? RCA: How can we ensure that the liability exposure for the owners,
builders, manufacturers, engineers, etc. are not increased? RCA: Can a new sustainable building code incorporate the changing
materials and technologies? RCA: How are energy codes related to building codes? NADAV MALIN
RCA: What do you see as the future of green building? What is your
sense of the market out there? RCA: What role do building codes play in this future? On the positive side, building codes have the potential to require better
buildings that less scrupulous people may not otherwise provide.
However, I hesitate to endorse using codes as a broader social document
because I believe they serve as only the nuts and bolts of construction
and design, and may not be the best avenue for raising consciousness
about the larger issues of sustainable building. Nonetheless, I do
believe performance-based codes are necessary to allow and encourage
energy- and resource-efficient design.
RCA: How do you think the adoption of the IBC will change the
building sector? Do you think the proposed performance-based IBC will open
the market for alternative building systems? RCA: Do you foresee a need for prescriptive-based codes for new
building technologies? Especially for the average builder? RCA: What are the barriers with performance-based codes? Under the performance-based sections of the codes today for structural
members, the code tells you how much load the building needs and you can
use whatever material you want to fulfill the load requirement. For most
materials, the performance requirements are sophisticated enough that it
is relatively easy to ascertain if the criteria has been satisfied. If
the building inspector is not familiar with the material, however, the
inspector will have no basis to determine its strength and reliability.
Over time, low-impact designs will develop base testing criteria so they
can avoid going through a time-consuming and expensive approval process.
RCA: How do you think insurance agencies and banking groups will
respond to changing codes? Bureaucracies like to pigeonhole things into a limited number of slots.
They'll welcome some new materials, but when faced with a vast number of
products and designs they will get nervous.
On the other hand, the insurance agencies have begun opening their arms
up to alternative energy systems because these systems can provide
uninterrupted back-up power during natural disasters, which helps
mitigate power-related losses. And there is increasing support in the
industry for promoting energy efficiency because it can help reduce
global warming and climate change, which is linked to an increase in
natural disasters. Our task is to show them how disaster-resilient,
green building practices can further reduce risk and minimize losses.
RCA: What steps need to be taken to integrate alternative building
into the mainstream? RCA: What is your vision for the proposed summit? I would like to see the codes recognize the broader environmental impacts
of different technologies so they inherently encourage more sustainable
building practices and increase
the flexibility for new and different design approaches.
It seems almost certain the IBC will be performance-based, but we need to
figure out what areas of performance the IBC is looking at and how we can
influence this process. Are they looking at standards for a building's
global environmental impact and/or indoor air quality, or are they only
examining a building's structural safety and/or weather resistance? And,
as I said earlier, how are these new performance-based goals going to be
measured? How will a new system meet the requisite targets? Further,
what route should we follow to eventually develop prescriptive-based
codes for some of these alternative systems, including making them
regionally appropriate? Hopefully, the summit will be the first step in
developing a game plan to address these critical issues.
LYNN SIMON
RCA: What has been your experience with building codes? How have
building codes impacted your work designing sustainable buildings? Overall, however, there is a strong resistance to try new
building systems because it is a conservative profession and there is a
certain comfort level associated with conventional wood-frame
construction. Builders and code officials are familiar with
stick-framing and they don't expose themselves to liability when using
it. This aversion to change, however, stifles advancement in the
building industry and perpetuates our unsustainable use of resources and
energy. It is critical for codes to increase their flexibility and
allow, if not encourage, innovation. Ultimately, we must develop and
enhance markets for affordable resource-efficient products and practices,
and create a shift towards sustainable building codes as well as
sustainable land use and energy policies.
RCA: Do you see performance-based codes as the solution? What are the
disadvantages? RCA: Do you see a role for prescriptive codes? Prescriptive codes, however, will only be developed once new
systems are thoroughly tested and proven. This all leads back to the
pervasive issue of funding. Today, manufacturers pay to test their
products. However, start-up manufacturers may not be able to pay for
this process, as it is very expensive. Further, it is hard for builders
to trust manufacturers' testing claims when they have an obvious vested
interest in the results. The government should step up to the plate and
fund projects in national labs and other independent facilities which
research and test new building designs and products. It is of national
importance that we reduce resource consumption and create sustainable
communities. Government-sponsored testing will serve the dual purpose of
cultivating and enhancing markets for new products and providing
independent verification of a product's worth.
RCA: How do you think the proposed performance-based IBC will change
the building market?
Is it the green light to green building that many have been waiting
for?< RCA: What will be the role of local codes once the IBC comes into
effect? States and localities will adopt the IBC as written, or they will tailor
it to suit their needs. Local codes are probably the best arena for
developing prescriptive requirements for alternative systems because they
allow for regional and political considerations. Some localities are
ecologically minded, some recognize the economic potential in using local
materials and some are looking for ways to construct low-income housing
projects.
For example, at Global Green we are working with the city of Los
Angeles on a pilot project to green affordable housing. The goal is to
foster community environmental stewardship through the construction of
inexpensive, resource-efficient housing. This housing will enable more
low-income families to become homeowners by lowering overall expenses
(for example, reducing energy bills and maintenance costs). Part of this
effort includes working with city agencies to develop new code policies
that will examine broader health and safety implications. It is a slow
process, but the city is committed to advancing sustainable strategies.
RCA: What do you see as the main goal of the proposed building codes
summit? Why will the summit be necessary if the IBC is going to be
performance-based and therefore allow alternative construction and
design? The summit is definitely necessary even if the IBC is
performance-based because there is a lot of lobbying and educating that
needs to occur. If the builders don't know or trust alternative products
and designs, they aren't going to use them. In addition, we really have
to target the large-scale production builders, consumers and others in
the mainstream to convince them of the value of resource-efficient design
both in the short- and long-term. Once they recognize the social,
economic and health values associated with conservation and the use of
nontoxic materials, they are more likely to open their minds to new
products and building strategies.
i. Nicholas Lenssen and David Roodman, "Making Better Buildings,"
State of the World 1995, Worldwatch Institute, Washington, DC, 1995
ii. Id.
iii. Id.
iv. National Association of Home Builders, Understanding Building
Codes and Standards in the United States, Home Builder Press, Washington,
DC, 1989
v. John A. Kilpatrick, Understanding House Construction, Home
Builder Press, Washington, DC, 1993
vi. Athena Swentzell Steen and Bill Steen, The Straw Bale House,
Chelsea Green Publishing Company, White River Junction, VT, 1994
vii. Understanding Building Codes and Standards in the United
States, 1989
viii. Paul Graham McHenry, Jr., Adobe and Rammed Earth Buildings,
University of Arizona Press, 1984
iv. The Straw Bale House
x. Prescriptive provisions in codes are desirable because they simplify
the building process by providing a blueprint for design and construction
and eliminating risk and liability
xi. Understanding Building Codes and Standards in the United
States, 1989
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