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 sheltersforall.org.