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" The major earthquakes in Haiti, Chile and now Southern California and Mexico this year highlight the power of building codes in saving lives and structures. Building codes, the critical provisions for minimum levels of safety in building design and construction, can be the difference between minimal property damage and outright ruin. Numbers from this year&amp;#039;s two biggest temblors tell the grim tale: The magnitude 7.0 quake that shook Haiti&amp;#039;s crowded capital Port au Prince in January killed some 230,000 people and collapsed a similar number of buildings. Six weeks later, an offshore earthquake 500 times as powerful rattled Chile, where the death toll remains in the low hundreds. Chile&amp;#039;s damage, while widespread, pales in comparison to Haiti&amp;#039;s mountains of rubble. Experts attribute a good portion of the different aftermaths to construction norms in the two stricken countries.  &amp;quot;In Haiti, there are no building codes enforced at all,&amp;quot; says Andre Filiatrault, director of the Multidisciplinary Center in Earthquake Engineering Research (MCEER) at the University of Buffalo. Filiatrault visited Haiti after the recent earthquake. On the Chilean side, visiting MCEER associates &amp;quot;saw a completely different story,&amp;quot; Filiatrault says. Advanced codes on par with those in the United States, developed over a long history of Chilean earthquakes, helped avoid &amp;quot;the whole level of devastation we saw in Haiti.&amp;quot;  In the U.S., disasters from hurricanes to tornadoes to wildfires have promoted architectural innovation, toughening the rules under which homes must be built. In crafting these building codes, engineers must weigh the economics of girding a home against an unlikely natural disaster. &amp;quot;We could build something that could stand up to virtually anything, but you probably won&amp;#039;t want to live in it and you probably couldn&amp;#039;t afford it,&amp;quot; says Tim Reinhold, senior vice president for research and chief engineer at the Institute for Business and Home Safety (IBHS).  In balancing safety and cost, most states and municipalities in the U.S. have adopted the well-regarded code created by the nongovernmental, nonprofit International Code Council. Governments then tailor this &amp;quot;model code&amp;quot; to regional geology, meteorology, and socioeconomics.  Places threatened by natural disasters often go beyond the code, adding amendments that call for different construction techniques and products. Homeowners&amp;#039; insurance companies often encourage builders and clients to make residences as robust as possible. &amp;quot;We&amp;#039;re big advocates for the building code arena and to understand and improve them, but what we really want is for people to build beyond code,&amp;quot; says Michael Milligan, a loss mitigation administrator for the insurance company State Farm.  Milligan and other experts interviewed for this story point to IBHS&amp;#039;s &amp;quot;Fortified . . . for safer living&amp;quot; program. It offers comprehensive recommendations for home builders in disaster-prone areas, such as the five described below. If your home happens to be in one of these spots, here&amp;#039;s how building codes can help. Scenario: Earthquake Place: Los Angeles, California It often takes a disaster for people to put in the extra money and effort to make buildings tougher. Chile learned this lesson in 1960, when a magnitude 9.5 quake\u2014the most massive quake in recorded history\u2014killed around 5000 people and caused several billion dollars in property damage (adjusting for inflation). That experience, along with constant reminders by subsequent large quakes in the area, spurred Chile&amp;#039;s government to adopt stringent building codes to protect against seismic events.  The wake-up call for much of California came after the San Fernando quake of 1971, says Charles James, the director of the Earthquake Engineering Library at the University of California\u2013Berkeley (UCB). Half a billion dollars in damage and the loss of 65 lives led to building code changes across the Golden State. For starters, the Alquist Priolo Special Studies Zone Act forbade the building of new homes on active fault lines.  The 1994 Northridge earthquake in Los Angeles pushed that city&amp;#039;s regulatory efforts further still, and L.A. has remained at the forefront of seismic building codes. &amp;quot;They have enacted ordinances which are very proactive and go beyond the model code,&amp;quot; says David Cocke, president of the engineering firm StructuralFocus and a representative of the Structural Engineers Association Of Southern California (SEAOSC).  One ordinance addresses tuck-under parking, in which the first floor of a building acts as an open-air carport with structural columns bearing the load of the overhead building. The Los Angeles ordinance requires retrofitting these &amp;quot;soft floors&amp;quot; with shear walls and steel frames. Shear walls are braced to counter the horizontal forces, or &amp;quot;lateral loads,&amp;quot; that a structure undergoes from sudden terra firma displacement in an earthquake.  Steel connectors between structural elements in residential wood homes are another way to transfer lateral loads during an earthquake. Also, to prevent the splitting of wooden sill plates\u2014the bottom horizontal part of a wall\u2014builders use square plate washers to connect these members to the anchor bolts that drive down into the concrete foundation. &amp;quot;These are small details that would not be considered in a nonseismic zone,&amp;quot; Filiatrault says.  The core concept is to prevent structural collapse. The building may have to be condemned, but at least whoever is in it won&amp;#039;t die, Filiatrault says. One common way to prevent buildings from collapsing is the &amp;quot;weak beam, strong column&amp;quot; concept. Basically, the columns in a home are built strong enough to not buckle under the maximum force a horizontal beam can impose on them. So even if the beams break, the structure has a good shot of avoiding outright collapse, Filiatrault says. Extreme Code Perhaps the most advanced quake-mitigation technology is &amp;quot;base isolation.&amp;quot; It appears in newer bridges, structures and some retrofitted buildings including Los Angeles&amp;#039; City Hall. Base isolation essentially functions like a shock absorber so a building does not sway violently even as the earth shakes below. It can be done by sandwiching multiple layers of rubber and steel between a building and the ground, or by fitting the buildings with sliding joints and hinges. Base-isolated buildings can experience one-third to as low as one-fifth of the horizontal acceleration that regular structures do during an earthquake.  The technology has rarely been applied to residences, with a few exceptions. After losing his Oakland home to a wildfire in 1991, Randolph Langenbach, a retired senior analyst at FEMA and a professor emeritus of architecture at UCB, started from scratch. He designed a &amp;quot;damped sway foundation system&amp;quot; that wedded vibration-absorbing, four-foot-long fluid dampers to a steel frame. &amp;quot;This is the only home with this design,&amp;quot; Langenbach says. Building the residence this way was more economical than the standard code solution: burying beams deep into the local clay-like soil. To develop the method, Langenbach studied how low-tech, traditionally constructed timber and masonry homes in Kashmir and Iran hold strong during earthquakes. He thinks there is much to be learned from indigenous architectures that have been honed in quake-plagued environments.   --&amp;amp;gt;  Scenario: Hurricane Place: Miami-Dade County, Florida The University of Miami&amp;#039;s athletic teams\u2014the Hurricanes\u2014perfectly characterize southern Florida as ground zero for many Atlantic-spawned mega-storms. Miami-Dade and Broward counties, located at Florida&amp;#039;s southeastern tip, have accordingly developed some of the strongest hurricane building codes in the world.  Protecting a home from this type of damage begins at its exterior envelope. South Florida has been particularly innovative in its codes on impact resistance\u2014the ability of windows, doors and walls to sustain blows from flying objects. &amp;quot;The implementation of impact resistance was pretty much spearheaded by this county in 1994 after Hurricane Andrew,&amp;quot; says Jaime Gascon, chief of the product control division for Miami-Dade County.  Gascon explains that to be code-worthy in Florida, buildings&amp;#039; envelope elements must withstand the &amp;quot;large missile test.&amp;quot; This test uses a cannon to hurl a 9-pound 2 x 4 at 34 miles per hour into sample envelope products. After taking the hit, laboratory-generated wind and rain buffets the product to make sure it can hold up under hurricane conditions.  This large-missile-test standard is applicable on a structure from the ground to 30 feet in height, Gascon says. Above that, the small-missile test takes over. This consists of 10 3\u204416-inch steel ball bearings fired at nearly 90 miles per hour, also followed by wind\u2013rain cycling. This test simulates smaller objects pelting buildings, such as loose gravel flying from nearby rooftops in a storm. The idea is not to test products when they&amp;#039;re &amp;quot;nice and new,&amp;quot; Gascon says, but after they&amp;#039;ve taken a hurricane-worthy beat-down.  To withstand a hurricane, the inside of a home needs shoring up as well. Those same connectors that make homes more resilient during earthquakes also protect them from winds. The goal is to provide a &amp;quot;continuous load path&amp;quot; to redistribute the pressure of the wind on the home&amp;#039;s roof and frame. &amp;quot;You want to get the load from where the wind blows on the building and make a chain from there down into the ground,&amp;quot; says Randy Shackelford, a research engineer with Simpson Strong-Tie, the world&amp;#039;s leading makers of structural connectors.  In 1999, engineers developed these techniques after inspecting homes in South Carolina that had been wrecked by Hurricane Floyd. &amp;quot;We cut [the homes] to pieces and looked at the strength of their connections,&amp;quot; IBHS&amp;#039;s Reinhold says. They learned that wall members without connectors strapping them together were so weak that only 10 percent of their strength was being engaged.  Another tough code in Miami-Dade and Broward Counties was introduced after a pounding from Hurricane Wilma, the most intense storm on record in the Atlantic Ocean. Along Brickell Avenue in Miami, exterior glass lights in a number of buildings shattered and peppered adjacent buildings with shards. Now glass lights must be made from laminated, tempered, toughened glass. Sticky resins hold shards together to prevent shattering, instead causing broken glass to splinter in a spider-web pattern. The insurance industry, which also takes a financial battering as the claims for shellacked homes and businesses pour in after hurricanes, has helped establish a retrofit code for older homes. Provisions include window shutters and more straps to connect roofs to every single truss in the home.  Extreme Code Many builders have claimed highly hurricane-proof residences over the years. A number of these homes are circular in shape, such as the prefabricated homes made by Deltec, a North Carolina\u2013based builder. Deltec says it has never lost a circular home to hurricanes in over 40 years of construction. The company credits its &amp;quot;radial engineering&amp;quot; wherein roof and floor trusses link back to the home&amp;#039;s center like spokes on a wheel, helping to dissipate gale forces around the structure.  In the expert-backed IBHS Fortified program (which does not endorse circular homes) houses must withstand an additional wind speed of 20 miles per hour over model codes. All walls must be shear walls anchored to the floor or foundation.   --&amp;amp;gt;  Scenario: Tornado Place: Norman, Oklahoma Much of the wind-resisting technology that battens down homes in hurricane zones also applies to &amp;quot;Tornado Alley,&amp;quot; the expanse between the Rocky Mountains and the Appalachians where twisters strike most in the U.S. Many homes employ connectors, but building codes tend not to mandate them as strictly as in Florida. That is because whereas hurricanes are massive storms that can blanket whole states, tornadoes typically only tear through a town-size area at a time.  As such, rendering houses as fortress-like, tornado-repelling structures does not make economic sense. &amp;quot;The chances you&amp;#039;re going to get hit regardless of how strong a tornado is in a particular house is like one in 5000 per year,&amp;quot; Reinhold says. &amp;quot;That&amp;#039;s well beyond what we&amp;#039;re going to design for.&amp;quot; Instead, building codes in Tornado Alley focus on preserving human life in safe rooms, also referred to sometimes as storm cellars or shelters.  This is the case in Norman, Okla., where &amp;quot;hardly a week goes by when we don&amp;#039;t see a storm cellar being built,&amp;quot; says Patrick Copeland, a building official for the city of Norman.  FEMA has supported a number of grant efforts over about the last decade to promote safe rooms. Some 20,000 residential safe rooms have been set up with more than $50 million of federal funds, as well as more than 500 larger community-level safe rooms.  In Oklahoma, over 6000 safe rooms have been made since 1999 when a spate of twisters destroyed about an equal number of single-family homes. When a big F4 tornado came through Oklahoma City in 2003, FEMA attributed the zero-fatality figure to all the safe rooms in place. (The &amp;quot;F&amp;quot; scale for tornadoes is the Fujita-Pearson scale, similar to the Saffir-Simpson Category system for hurricanes that goes from 1 through a devastating 5.) A number of recent building codes, including the ICC 500 and the FEMA 361 Second Edition in 2008, have redefined the standard for tornado and hurricane safe rooms to have them provide &amp;quot;near-absolute protection.&amp;quot; This means withstanding wind speeds of 250 miles per hour and impacts from objects\u2014a 15-pound 2 x 4 in tests\u2014hurtling at 100 miles per hour.  Safe rooms often are big steel or concrete boxes that can go in a home&amp;#039;s first floor, garage or basement. Doors swing inward so people can escape or get air even if debris blocks the entrance, says JoAnne Sellars, assistant state fire marshal of Oklahoma.  She recently visited a safe room set up at a school. Sellars says the structures can serve multiple purposes, including storage for library books, for example. When inside a safe room, she says &amp;quot;you know you&amp;#039;re somewhere different because there are no windows.&amp;quot; Reinhold says a shelter about 8 x 8 feet that holds a family of up to six costs $2500 to $7500. Extreme Code In terms of structural resistance, Reinhold says &amp;quot;the only things really designed for tornados are protective areas around nuke plants.&amp;quot; He says that missile tests for reactor housings substitute flying cars and I-beams for the lumber used in the South Florida tests. This is because a radiation leak would make a bad, stormy situation a great deal worse long after the tornado has blown through. &amp;quot;The typical probabilities we play with for this sort of bad thing happening any given year is one times 10 to the sixth. A very, very rare event,&amp;quot; Reinhold says.   --&amp;amp;gt;  Scenario: Wildfire Place: San Diego County, California It&amp;#039;s late summer in San Diego County and the dry, gusting Santa Ana winds have kicked up. A single spark has the potential to set tens of thousands of acres ablaze.  To counter this annual fire-season threat, San Diego County has adopted among the most stringent wildfire codes around. Statistics bear out their efficacy. In the massive 2007 fires that swept through the county, some 8300 structures were within the fire&amp;#039;s perimeter and a total of 13 percent of homes were destroyed. But most of these buildings were older; new homes built under stricter codes enacted in 2004 had losses of 2 percent. &amp;quot;That says to us that these codes really do work,&amp;quot; says Clay Westling, a senior structural engineer at the County of San Diego Department of Planning and Land Use. That batch of building codes was drafted in response to the devastating 2003 wildfires that included the largest single conflagration in California&amp;#039;s history, known as the Cedar Fire. Afterward, planting trees, plants and shrubbery\u2014all fuel for a blaze\u2014became prohibited within 30 feet of all groups of homes.  Fences coming within 5 feet of the home must be made of noncombustible or ignition-resistant material to &amp;quot;avoid a wick effect of bringing fire right up to the house,&amp;quot; IBHS&amp;#039;s Reinhold says.  For the home itself, according to a summary document, &amp;quot;exterior wall surfaces must be non-combustible, ignition-resistant material, heavy timber, or log wall construction,&amp;quot; regardless of clearance from brush. Code-clearing examples include stucco, masonry, and cement fiberboard.  Roofs also must be Class A, which is &amp;quot;the highest in terms of burn-through,&amp;quot; or &amp;quot;the amount of time fire would take to burn through the material,&amp;quot; says Dave Walls, the executive director of the Building Standards Commission in Sacramento, Calif. Skylights must be tempered glass; exterior doors must be noncombustible or made of thick, solid-core wood or have a fire burn-through of not less than 20 minutes.  One of the most important firefighting building codes centers on an easily overlooked part of a house: the outside vent from the attic. When doing postmortems on torched homes many years back, researchers discovered that burning embers often found their way into a home through these vents. But products such as noncombustible mesh frames or baffles to allow air out but no embers in have only recently entered the market. &amp;quot;Wind-driven embers are the ignition sources for a lot of these fires, so building a home where embers won&amp;#039;t get in and contact combustible materials is a key aspect of home design,&amp;quot; Westling says.  Extreme Code A wildfire-proof home? A concrete home built right into the side of a mountain in Santa Monica, Calif., by architect Eric Lloyd Wright, the grandson of famed architect Frank Lloyd Wright, appears to fit the bill.  During construction in 2007, the home did indeed survive a wildfire that destroyed Wright&amp;#039;s main residence nearby and charred the landscape. By being built into the contour of the sloping land and presenting a relatively small exterior, fires flowed right over the residence, Wright told ABC News.   --&amp;amp;gt;  Scenario: Flood Place: In All Likelihood, Where You Are &amp;quot;Floods are the most common and widespread of all natural disasters,&amp;quot; according to FEMA. &amp;quot;Most communities in the United States can experience some degree of flooding after spring rains, heavy thunderstorms or winter snow thaws.&amp;quot;  The widespread history of damage from floods is a big reason why most homeowners&amp;#039; insurance companies won&amp;#039;t provide coverage against them. The federal government created the National Flood Insurance Program (NFIP) in 1968 to offer some protection for building owners and renters who take steps to mitigate their risk of flooding.  It took until 2000, though, for building codes to be brought into line with the NFIP. The favored, toughest codes are drawn from the American Society of Civil Engineers (ASCE) 24-05 document, which is now five years old. FEMA has also created national maps classifying the threat to communities in a floodplain to inform their code managers.  &amp;quot;Comprehensive model code flood provisions have only come on the scene in the last decade,&amp;quot; says John Ingargiola, senior engineer and team leader of the Building Science Branch and Risk Reduction Division at the FEMA HQ Mitigation Directorate in Washington, D.C. &amp;quot;The real opportunity for improvement lies in the increased adoption and enforcement of these codes and standards in flood-prone areas,&amp;quot; Ingargiola says.  The most obvious way to beat these rising, rushing waters is to build higher than the height you expect it will be in the event of a flood. Current codes adopted in most coastal areas are pegged to about a 100-year base flood elevation, meaning that each year there is a 1 percent chance of a flood reaching that level. When statistically applied over a 30-year mortgage, however, coastal homes end up with a solid 26 percent chance of a watery demise, according to the IBHS, so floods remain a fact of life for many homeowners.  One way to promote flood-code awareness has been the Community Rating System (CRS) that awards points for going over and beyond FEMA&amp;#039;s minimums, says Rich Roths, principal planner and the NFIP Region V program manager. More points equal a reduction in premium for NFIP coverage. Roseville, California stands as the only Class 1 community, so homeowners there receive a 45 percent cut in their rates. The city does this by keeping less than 7 percent of its buildings in a designated floodplain; those that are built there must be 2 feet above bade flood elevation. The government also clears creeks annually of fallen trees and debris that could contribute to flooding. Other high scorers include Tulsa, Okla., and King and Pierce counties in Washington.  Rhode Island requires all buildings in the floodplain to be designed and certified to ASCE 24-05 specs, plus setback requirements from the coastline to account for erosion, Ingargiola says.  He adds that this last bit will be key for the future of flood codes as sea levels likely rise as a result of climate change.  Extreme Code  Hurricane Ike demolished the south Texas coast in 2008, ringing up property damage north of $12 billion, the third costliest storm ever in the nation. Northeast of Galveston, a storm surge of about 15 feet combined with 20-foot waves to wash out almost every home on the Bolivar Peninsula.  But 10 homes out of 270 made it through, just a short block from the beach. Residents had previously nicknamed them the &amp;quot;birdhouses.&amp;quot; Elevated to 26 feet, the survivors were significantly higher than the already-tough code\u2014around 17 feet on that part of Bolivar. The birdhouses were built according to the Fortified code-plus recommendations of the IBHS. Reinhold says he&amp;#039;d like to see the NFIP incentivize all homeowners to go beyond the 1 percent chance of flooding per year NFIP standard and instead aim for a 500-year, 0.2 percent probability.  As with all building codes, raising the proverbial bar higher for natural disaster protection through cooperation with industry is a work in progress. Every disaster teaches something new that can soften the blow of the next event, says MCEER&amp;#039;s Filiatrault. Every building built to the best codes then becomes a &amp;quot;living laboratory,&amp;quot; he says, for scientists, engineers and survivors. "^^<http://www.w3.org/2001/XMLSchema#string>
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