Are Sustainability and Resiliance Mutually Exclusive?

A recent article in the Bulletin for Earthquake Engineering outlines the ways in which sustainability and hazard-resilience can and must work together for safe housing in Haiti. “While many agree that sustainable redevelopment and self-reliance is essential for Haiti, few appreciate how it can be practically achieved, particularly in the domain of urban residential redevelopment” (p. 2).

The authors outline the types of materials have been used in Haiti: “Historically, due to the lack of wood, for use either as formwork or as a partitioning alternative, and the high cost of steel, cement and quality aggregate, Haitians employed construction with heavy masonry walls made of hand pressed concrete masonry units (CMUs) and lightly reinforced, undersized concrete columns, made with inferior raw materials and having inadequate strength and ductility. This combination, along with the lack of beams that would better engage the columns against earthquake loads, created systems that actually performed well under strong winds common to the Caribbean, but were conversely proven to be extremely vulnerable to earthquakes, failing through brittle collapse modes, as documented in the authors’ personal reconnaissance database through their field work in Haiti” (p. 2).

The authors explain that Haiti has a unique mix of requirements — it is the poorest nation in the Western Hemisphere, has suffered massive deforestation, and is in areas prone to both earthquakes and hurricanes. Moreover, Haiti’s government shows very little oversight in construction. They conclude, “The lack of locally-available construction materials, including the wood necessary for formwork to cast earthquake-resilient concrete frames, the steel necessary to provide strength and robust ductile behavior, or the quality masonry for confined or load bearing masonry construction makes the expense of this style of construction too great to serve the needs of the majority of displaced Haitians living in extreme poverty” (p. 4).

They conclude, “As Haiti has taught us, vulnerability stems from two potential sources: (1) lack of knowledge and (2) lack of resources to implement this knowledge properly… The only remedy is to flank these efforts with policies that encourage and support research to develop alternative, low-cost, sustainable housing that provides hazard resilience, while operating within the economic and cultural constraints of these regions so that all families will have a legitimate pathway to empowerment.” (p. 7).

Do you have ideas for how to make buildings both sustainable and resilient in Haiti? Submit your proposal to

Hemp Houses

A 2008 article from Science Daily discusses the use of hemp in the creation of houses worldwide. Professor Peter Walker, Director of the BRE Centre for Innovative Construction Materials, said: “The environmental impact of the construction industry is huge. For example, it is estimated that worldwide the manufacture of cement contributes up to ten per cent of all industrial carbon dioxide emissions… We are looking at a variety of low carbon building materials including crop-based materials, innovative uses of traditional materials and developing low carbon cements and concretes to reduce impact of new infrastructure. As well as reducing the environmental footprint, many low carbon building materials offer other benefits, including healthier living through higher levels of thermal insulation and regulation of humidity levels.”

A 2009 article about the same research group investigates the use of hemp-lime — a lightweight composite building material made of fast-growing hemp bound by a lime adhesive. Director Walker stated, “Using renewable crops to make building materials makes real sense – it only takes an area the size of a rugby pitch four months to grow enough hemp to build a typical three bedroom house… Growing crops such as hemp can also provide economic and social benefits to rural economies through new agricultural markets for farmers and associated industries.”

Is hemp the future of sustainable housing?

Guest Blogger – The Benefits of Multi-Hazard Engineering

Hurricane Katrina and the Indian Ocean Tsunami are among the most serious and devastating natural disasters in recent history. They are both known worldwide for the many lives lost and the extreme property damage that resulted. Hurricane Katrina struck the Gulf Coast in 2005, primarily hitting Louisiana, Mississippi, and Alabama. Hurricane Katrina was a Category 3 hurricane when it made landfall and was the costliest hurricane in the history of the United States, causing $81.2 billion in damage. New Orleans was among the cities to be hit the hardest, as protective levees broke and much of the city flooded. Storm surge wave heights exceeded twenty feet and flooded 80% of the city. The Gulf Coast of Mississippi was equally devastated by storm surge and wave action as well as winds. The Indian Ocean, or Boxing Day, Tsunami occurred on December 26, 2004, originating off the northwest coast of Sumatra, Indonesia. Its destructive effects were felt across the Indian Ocean and all the way to the eastern coast of Africa. The tsunami resulted from a magnitude 9.2 subduction earthquake. The waves propagated from the epicenter of the earthquake and caused the most damage in Indonesia, Thailand, Sri Lanka, and India. Wave heights exceeded 10 meters and reached several kilometers inland in Thailand, as shown below by the markers placed along the coast in Phuket. It is estimated that 230,000 people were killed as a result of the tsunami, in part because of the absence of a warning system. The tsunami was especially devastating in small Asian fishing villages that were built along the coast. Not only did these disasters cause immediate destruction, but for some areas much of the devastation remains today, as shown in the image above, taken two years after the Indian Ocean Tsunami.

Hurricane Katrina and the Indian Ocean Tsunami remain pivotal events in my life due to personal experiences with the resulting devastation. I had the opportunity to visit New Orleans after Hurricane Katrina with my Computational Methods class at the University of Notre Dame to study the levee system and its failure. I was also involved in forensic engineering research that used satellite imagery and aerial photography to investigate the causes of damage to structures near the coast in Mississippi. In addition, I participated in a Research Experience for Undergraduates (REU) program, Interdisciplinary Studies in Tsunami Impacts and Mitigation (ISTIM), at the University of Notre Dame during the Summer of 2007. As part of this program, we traveled to Phuket, Thailand to see first-hand the devastation caused by the tsunami and learn how to better design and build structures to prevent future deaths and destruction from similar disasters. While the occurrence of these hazards is beyond our control, novel structural engineering approaches have the ability to reduce their consequences.

It became apparent during these site visits and research experiences that structures in these areas are affected by multiple hazards, leading to unexpected effects. For example, many structures close to the coast in the southeastern United States are not only affected by the strong winds associated with a hurricane but also the damaging effects of storm surge and waves. This can be seen in the images below, taken after Hurricane Katrina, which show complete destruction of homes due storm surge and waves (left) in close proximity to homes that suffered minor wind damage but were elevated from the storm surge (right). In addition, the Indian Ocean Tsunami showed that structures near the coast in strong seismic areas may be affected by both earthquakes and tsunamis. And finally, the 2010 Haiti Earthquake occurred in an area typically affected by hurricanes. Therefore, most structures are not vulnerable to one single hazard and managing hazards individually may not yield the most efficient and effective designs. In addition, the most extreme load conditions, two hazards acting together, may not be considered.

These and similar observations are what generated the relatively new area of multi-hazard engineering. Multi-hazard engineering aims to use available resources most effectively to design safe structures that are able to withstand a range of natural hazards. This approach involves an understanding of all of the hazards that could potentially affect a structure and the use of this knowledge to determine which aspects of the structure may be most vulnerable. Then, robust design features can be incorporated in order to enhance performance when considering individual hazards or the combined loading from several hazards. Post-disaster site visits and satellite imagery are invaluable to the determination of these robust design features. For example, the building shown below is in the region hit by the 2004 Indian Ocean Tsunami. The lower level of the structure bore the brunt of the damage. The walls perpendicular to the wave direction have been completely destroyed. The structure, however, remained standing. After the perpendicular walls were broken, the water was able to flow through the first floor diminishing the overall loads on the structure. Post-disaster photography, such as this, can help in determining better design practices for the future. Breakaway walls on the lower levels of structures in tsunami-prone regions would allow the water to flow through instead of causing a build-up in the pressure and the forces on the ocean-side wall and other foundation components.


Designing low income urban housing comes with its own set of unique challenges without consideration of the multiple hazards with which the structures may be faced. A multi-hazard approach, however, can readily be incorporated into the design stages in order to ensure that the resources that are available are being used to most effectively resist the hazards. It is envisaged that a strong, multi-faceted structural system promises to mitigate damage from many hazards. Structural engineers have the unique ability to positively influence society in an important way by improving the resiliency of structures to hazards, allowing people all over the world to have access to safe structures in which to live and work, Shelters For All!

– Megan McCullough, Civil Engineering Graduate Student, NatHaz Modeling Laboratory, Department of Civil Engineering and Geological Sciences, University of Notre Dame

Sustainable Housing: South African Case Studies



Photo by Corvair Owner

A 2010 article from Construction Management and Economics outlines nine case studies of different types of sustainable housing worldwide with the goal of improving the living conditions of those in South Africa. They examined these cases in terms of the seven principles of sustainable construction (Kibert 1994; Hill and Bowen 1995): 1) Minimize resource consumption, 2) Maximize resource reuse, 3) Use renewable or recyclable resources, 4) Protect the natural environment, 5) Create a healthy, non-toxic environment, 6) Pursue quality in the built environment, and 7) Promote socio-economic sustainability. From those seven principles, 49 indicators of sustainability were used to assess the merits of the construction.

Many sustainability practices had been implemented in these cases — energy- and water-efficiency, reuse of old buildings, non-use of toxic materials, consideration for the natural environment. However, the support of sustainable building by the users was still low, and there were still high initial costs to developing sustainable housing.
What other factors need to be considered when thinking about sustainable housing?

Guest Blogger: Protecting Coastal Villages in the Developing World

On December 26th, 2004 the Indian Ocean tsunami caused devastation in fourteen countries including Indonesia, Sri Lanka, India, and Thailand.  Nearly two and half years later in the summer of 2007 I was doing research on sustainable structural design to resist natural hazards through a National Science Foundation program at the University of Notre Dame, which ended with a field study in Thailand.  Little did I know that this trip would be an eye-opening experience that would forever change my life.

I didn’t realize the need for sustainable housing in the developing world until I witnessed it first hand.  I was shocked to see that two years after the horrific event, communities in Phuket and Khoa Lak, Thailand were still in shambles.  Walls had been ripped out of houses leaving only the structural frames.  The remains of buildings were filled with debris of all sorts, and structural beams were bent and deformed beyond repair.  (See photos below).

Photo by Mary Beth Oshnack

Photo by Mary Beth Oshnack

Photo by Mary Beth Oshnack

While it was encouraging that reconstruction had begun in some villages, (see more photos) it saddened me to see buildings being constructed in the exact same areas where others were destroyed. Were these new structures destined to be subject to the same fate as their predecessors in the wake of another disaster?  For larger commercial structures like hotels, developers are willing to build closer to the shoreline and therefore risk being inundated in order to promote tourism and enable the guests to enjoy the natural beauty of the ocean.  It helps that these hotel chains can afford to rebuild after a structure is lost. But what is the solution for fishing communities who have to be near the sea to sustain their source of livelihood?  Can we provide shelters to help them live safely in the event of a natural disaster?

Photo by Mary Beth Oshnack

My trip to Thailand encouraged me to continue my research on tsunami inundation.  While as a graduate student at Oregon State University, I found that small seawalls cause a skyward deflection of incoming tsunami waves that dissipates energy, reducing the force on landward structures.  More on this research can be found here.

Discovering the degree to which a design concept like small seawalls could help entire communities in the wake of a disaster was a really rewarding experience for me.  I used my knowledge, experience, and passion for the subject to help find a solution to a problem that I genuinely cared about. And now I’m asking you to do the same! Let’s find a way to make affordable yet durable housing available in areas where materials are scare and challenges like growing populations and the threat of natural disasters are eminent.  Let’s find shelters for all!

– Mary Beth Oshnack, Senior Engineer in Training, GAI Consultants Inc. (Pittsburgh, PA)

Focus on What’s Important – Haiti Photos, January 14, 2010

Photo from National Geographic

Today we’re going to look back at the images of Haiti immediately after the magnitude 7 earthquake that struck nearly 2 years ago.

Photo from the National Geographic

Photo from National Geographic

There is a real need for sustainable, safe housing. You can be the one to change the future of places like Haiti. Join the challenge at

Guest Blogger: Housing and Infrastructure Needs in Central and South America

According to the latest U.N. report, the world population recently topped seven billion people.  As the world population continues to increase, so does the negative impact on both the environment and the communities most in need.  Over the past few years, while living, working and traveling in both Central and South America, I have witnessed this need firsthand and would like to quickly share two instances of this today.

In 2008 I was traveling with a group to Tegucigalpa, Honduras trying to gain support for the construction of a bridge project.  It was the rainy season and our group had heard lots of reports about mudslides taking out the roads and making roads inaccessible.  After arriving at the bus station in San Pedro, we took the one route to Tegucigalpa that was “accessible.”

Photo by Patrick McHugh

As can be seen, the road is almost completely wiped out, yet traffic was still traveling both ways on the small part of the road that remained.  I was not only amazed that the traffic was still flowing on such a dangerous road, but was just as amazed to learn how these roads were constructed.  From what I picked up from the locals, the area was basically cleared, tamped down and then poured with a thin layer of asphalt.  Certainly not the best approach given the environment in which it was built.

Additionally, this past year I lived in a small city on the western coast of Peru called Talara.  As can be seen in the picture below, the construction of the houses would not even be close to living up to the standards that we enjoy in the United States.  In the poorest areas, the houses were constructed solely of sheet wood walls, no floors and scrap metal for the roofs.

While Talara is a desert town, it is also subject to heavy semi-annual rains that can last months.  These heavy rains (locally called “El Nino”) destroy the homes and put an even greater strain on the ones most in need.   As local population climbs and natural resource demand grows in the area, the more complex and difficult these issues will become.

The need for innovative solutions in housing and infrastructure in developing nations is clear.  Furthermore these solutions must be economical, safe, and sustainable.  Without any of these adjectives the answer will come up short.

I encourage everyone to submit a design to Shelters for All and help by becoming part of the solution.

– Patrick McHugh — University of Notre Dame, CE, 2010 — Duke University, MEM, 2012