With each passing year, the occurrence of natural disasters becomes more frequent and the damage from such events remains catastrophic for homeowners and communities. Climate-related natural disasters have cost the United States more than $2 trillion since 1980, according to findings from the Disaster Medicine Fellowship at Beth Israel Deaconess Medical Center, and the count of billion-dollar natural disasters has increased from three in 1980 to 22 as recently as 2020.
Against this backdrop, fortifying the homes that are built is as important an endeavor as ever. To this end, the Department of Housing and Urban Development (HUD) tasked the Home Innovation Research Labs with developing a set of “practical, actionable guidelines” to assist builders and developers in constructing structures in a manner “that could improve residential resilience to natural hazards and integrate resiliency throughout the community.”
The final product is five volumes that cover designing for resilience against wind, water, fire, earth, and auxiliary hazards (such as extreme temperatures and hail). According to the authors, the resilience guides are intended to enhance and improve above-code performance while providing details on construction practices and common damage occurrences from various natural disasters.
“What’s unique about these guides is that [similar documents] provide a laundry list of natural hazards, correlate them in some way, and tell you the 15 things you need to do,” says John Peavey, director of the business science division at Home Innovation Research Labs. “The guides are totally different; they are defined in a way where if you are thinking about the type of damage you will sustain from this hazard, this is how you can mitigate, prevent, or minimize that type of damage.”
Before putting the guides together, data was analyzed identifying the most common types of natural disasters in the country as well as the areas of a home most impacted by natural disasters. A technical advisory group, which included builders, developers, designers, engineers, federal agency representatives, insurance industry representatives, code officials, product manufacturers, community officials, resilience advocacy groups, and public representatives, was assembled to provide guidance and review throughout the process. The goal was to create a set of practical, actionable guides for builders and developers. The advisory group prioritized “high-frequency damage” that occurs as the result of natural hazards over damage “that rarely occurs.”
In the case of wind-related damage—for which the most data was available for analysis—the roof covering, roof substrate, wall cladding, and windows were most frequently damaged. Damage to chimneys on single-family residences, however, occurs less frequently, and the guides suggest less prioritization for chimney fortification than construction practices to fortify roof coverings, continuous load paths, and garage doors.
“We were able to prioritize within our documents what type of mitigation area should be the focus. This study and these guides are not based on cost; that’s not the primary reason why you would prioritize one practice over another,” Peavey explains. “We recommend prioritizing that which happens the most and that which has the biggest damage range.”
The resulting guides each include one-page documents that identify a type of damage caused by a natural hazard, the frequency of occurrence, a suggested construction practice or practices to mitigate or help prevent the damage, a mitigation strategy, as well as the cost and benefit of the preventative practice. For the purposes of the guides, resilience was defined as the implementation of above-code practices, which differs by region and frequency of certain weather events in various parts of the country.
As an example, for wind resilience the guides identify fortification of roof deck and underlayment as a “high” damage frequency risk. The guides recommend strengthening roofs during the construction process by installing systems built for high-wind events. Each one-page document shares a dollar-sign equivalent cost estimate, ranging from low cost ($) to high cost ($$$). On the back of the document, specific construction practices are shared for decking, a secondary water barrier and underlayment, and fasteners for underlayment. Peavey says that while builders may not be able to strengthen all identified areas to above-code solutions, the guides help prioritize which areas of the home should be most fortified to produce resilient structures for natural hazards.
“What we also do [in the guides] is explain whether it’s difficult or not. Some of these things are easy to do, some are complicated,” Peavey says. “The cost does not drive [prioritization], and we also give multiple different ways to approach [an issue]. There is not only one way to achieve resilience.”
In the water resilience guide, the technical advisory group identifies roof underlayments, vents, wall assemblies, mechanical equipment, and freeboard elevation as the most frequently damaged areas of the home and, as a result, the most important areas to fortify. Roof assemblies, foundation components, and ducts or vents are most frequently damaged by fire events; post and beam connections, drywall, garage openings, roof-to-wall connections, and exterior walls are most frequently damaged by natural earth hazards; and siding and roof materials are most frequently damaged by hail events. In response to BUILDER, HUD says the resilience guides are intended to be living documents and will be updated periodically based on post-disaster damage assessment data.
By deemphasizing cost, Peavey says the guides have more utility to builders and developers. While cost is often a pain point when it comes to implementing above-code solutions, the guides help prioritize the most effective and resilient practices against common weather events. By doing this, he says it helps builders prioritize the allocation of limited resources in areas where practices can have the most positive impact. Beyond the prioritization and options to achieve resilience, he says an additional benefit of the guides to builders is their brevity and use of common language.
“You could print this one-pager from the guide [for a practice you have adopted], and now it becomes a marketing and educational piece for potential home buyers. ‘This is one of the resilient aspects I added to my building, this is the practice I have selected, [and] it was above code, etc.,’” notes Peavey. “To us, what makes this so much different from what’s available is that for builders and developers, they can use this document as a marketing tool.”
Peavey says several builders, including two companies that are part of the technical advisory group, have begun to integrate the documents into their operations by showing them to potential buyers.
“This is not the regular programmatic things that have been available. They are flexible enough that you can design a program with [them] or flexible enough that you can identify the two or three things that were [high-frequency occurrences] and address them,” Peavey says, adding that the guides are “written in layperson terms so anyone can understand. We wanted them to be not only accessible, but usable.”
