|Hazard Information for the Homeowner|
No matter where you live around the country, your home will be exposed to hazards. The National Institute of Building Sciences offers this page as an initial resource to help you prepare your home. It is intended to provide you with some tools to assess the particular risks for your area and steps that you can take to help make your home (and business too) safe and secure. As always, when making any changes to your home, be sure to check with a licensed professional or your local building department.
What are your risks? Whether you live in Alaska or Florida, your home is at risk from a number of natural and manmade hazards. Where you live will determine the potential hazards and whether your home is more likely to be exposed to earthquakes, high wind events, snow loads, flooding or wildfire (or, if you’re located next to a golf course, the occasional golf ball).
What are the minimum requirements for safety? Depending on when your home was built, it was most likely required to comply with a building code. Generally, new construction must follow a state or locally adopted building code. A building code establishes a minimum level of safety for the building occupants. In most cases, the code provides adequate protection against a hazard or allows occupants sufficient time to leave the building. Existing homes had to comply with the building code in place at the time of initial construction. When making renovations or additions, the alterations typically need to meet the code currently in place now.
How are codes developed and implemented? Building codes are developed at the national level through a process that brings together building experts and interested stakeholders. They are often referred to as "model codes” because they form the basis for the codes adopted at the state and local level. Most jurisdictions adopt a model code in its entirety or use it as the basis for their own code, adapting it to address specific local concerns or to make an aspect of the code more restrictive (such as increasing the wind requirements in an area at high risk of hurricanes). Many jurisdictions update their building codes when the new model codes are released, which occurs on a three-year cycle. Others adopt revised codes on a six-year cycle. Some jurisdictions rarely update their codes. And, there are even some jurisdictions that still don’t have a building code at all. Check with your local building department to find out what your jurisdiction requires.
How are current and future climate changes being addressed? Buildings are typically designed and constructed to respond to the hazards historically experienced in the particular area where they will be constructed. (For example, a building in a California will have to meet stronger earthquake requirements than one in Pennsylvania.) The building codes have a number of maps defining the regions of the country where specific hazards are more likely to occur based on a compiled history of data. However, with the recent climatic changes, the marked increase in the frequency and severity of natural hazards appears to defy these historical precedents. The building community is aware of these changes. However it is unclear how best to update the levels of performance in response to recent disasters that greatly differ from past events, or to predict performance needs for catastrophic events that may occur in the future.
Is it possible to build above the minimum requirements of the building code? Is there a benefit? The building codes are developed to provide a minimum level of protection for the homeowner but the homeowner can increase protection in a number of ways. The Insurance Institute for Business and Home Safety has developed programs for both new construction and retrofits of existing homes that include criteria for increased hazard protection. There is a benefit to going beyond the code requirements. Some homeowners’ insurance companies may provide reduced rates for homes that meet the FORTIFIED criteria.
How can I prepare for a disaster?There are several key steps to assure that your family is prepared in the event of a disaster. Having a disaster emergency plan and a preparedness kit is essential. The American Red Cross provides tips on preparing your family, businesses and schools. The Insurance Information Institute has an iPhone app, "Know Your Plan” which can assist in developing your plan.
Natural Hazards and Educational Resources
Homes in areas at risk of hurricanes are required to be built specifically to withstand high winds. However, practically every region in the United States is subject to some type of severe wind hazard that can readily exceed minimum requirements of even the best building codes. A house is much more likely to withstand such winds if its exterior walls are properly attached to its roof and foundation. The strength of the connections between the roof, walls and foundation is critically important for holding a house together. Outside of hurricane-prone regions, one way to minimize the risk of damage from high-winds is to still include the connections that tie the house together from the roof to the foundation, though they may not be required by code. For hurricane-prone regions, it is also important to protect windows, doors and garage doors from wind-borne debris protection (either with hurricane shutters or plywood) and to secure vents.
EarthquakesUnlike severe wind events, earthquakes occur with no warning so there is little opportunity to take cover or vacate an unsafe building. In certain states, such as California, where strong earthquakes occur frequently, people understand the value of building to modern seismic requirements. However, although the West Coast generally has the greatest earthquake activity, some of the largest earthquakes have occurred in the central United States, and the potential for earthquakes exists in almost every corner of the United States. Because big earthquakes occur with less frequency in other parts of the country, people are not aware of the risks and do not necessarily consider earthquakes as an important factor in construction. That is why the use of updated building codes with modern seismic provisions is even more important, because they create passive protections.
Most property insurance policies do not cover damage caused by floods, yet even an inch of water above the floor can have devastating results for a home and its contents. The Federal Government created the National Flood Insurance Program(NFIP) to provide this coverage to property owners. Homeowners are required to purchase flood insurance if they live in a floodplain that has a 1% annual chance of flood (also sometimes called the 100 year floodplain). However, 25% of all flood insurance claims come from homes outside a designated flood zone. The best advice for protecting against the risk of flood is to make sure you know whether flooding is a hazard on your site and, if you are building in a flood-prone area, to elevate the structure and follow appropriate construction guidelines and regulations for flood-resistant construction.
Always check with the local authority having jurisdiction to determine specific flood elevation and construction requirements.
According to U.S. population statistics, about 100 million people across the country now live in areas exposed to wildfire. Larger and more destructive wildfires increasingly are putting people and properties at risk. The cost of fighting these destructive fires continues to rise. Increasingly, firefighters, stretched thin by large fires, are forced to choose which homes and businesses to save. Often these choices are based on which structures are most accessible and defendable.
There are two primary areas of concern when it comes to minimizing the chance of a building igniting from exposure to a wildfire. First, a number of features and design details, such as flammable roofing and siding materials, can make a home more vulnerable. Second, the surrounding wildlands and vegetation near the house can provide a pathway for an approaching wildfire to get close enough for the flames to touch the structure or for radiant energy (like standing in front of a camp fire) to generate enough heat to cause a home to catch fire or break glass in a window. Additionally, wind-blown embers from a fire a mile away can fall on the house, nearby vegetation, or secondary buildings and cause them to catch fire. Making your home more fire-resistant and creating a perimeter that is clear of flammable materials can help reduce the risk.
When it comes to natural disasters, hail may not rise to the danger level of earthquakes and hurricanes. A hailstorm can, however, inflict a significant amount of damage in the form of shattered windows, pockmarks in siding, and can, most importantly, damage and destroy roof coverings.
There are approximately 3,000 hailstorms annually in the United States, resulting in an average of $1.6 billion in insured losses. Hail can potentially occur anywhere because it often is part of a strong thunderstorm, but some regions of the country are more prone to repeat hail damage. Knowing which roof coverings best resist the impact of hail damage can save time and money spent on repairs, not to mention prevent water damage that can affect ceilings, walls, floors, appliances and personal possessions.
Winter WeatherProperty damage related to freezing temperatures, the weight of accumulated of ice and snow and the resulting water damage, plagues thousands of homeowners each year and results in costly repairs. Nearly 75% of homes in the United States can expect to be exposed to below-freezing temperatures at some point during the winter months. With this in mind, it is important to consider factors that could put a home at risk from severe winter weather when building or retrofitting a house. Even parts of the Southern United States can be at risk of experiencing freezing weather-related damage. Though it may not be required by the building code, steps can be taken to minimize this damage.
Tornadoes are nature’s most violent storms. Spawned from powerful thunderstorms, tornadoes can cause fatalities and devastate a neighborhood in seconds. A tornado appears as a rotating, funnel-shaped cloud that extends from a thunderstorm to the ground with whirling winds that can reach 300 miles per hour. Damage paths can be in excess of one mile wide and 50 miles long. Every state is at some risk from this hazard. Some tornadoes are clearly visible, while rain or nearby low-hanging clouds obscure others. Occasionally, tornadoes develop so rapidly that little, if any, advance warning is possible. Before a tornado hits, the wind may die down and the air may become very still. A cloud of debris can mark the location of a tornado even if a funnel is not visible. Tornadoes generally occur near the trailing edge of a thunderstorm. It is not uncommon to see clear, sunlit skies behind a tornado. When a tornado strikes, having a designated safe area to shelter in place is extremely important.
There are a number of additional hazards that historically have not been a part of building codes. Unfortunately, bomb threats; chemical and biological agents; school shootings and a number of other manmade hazards have increasingly become a concern in today’s society.
Whole Building Design Guide Resources