Window and door codes, technologies, and designs are keeping today’s buildings intact and dry when extreme weather attacks.
By Greg Galloway, YKK AP America Inc.
As real estate broker Scott Papp and his wife Kym sat in their third-floor hotel room on Sept. 9, 2017, at the Hyatt House in Naples, FL, they watched out the window as Hurricane Irma transitioned from a Category 3 to a Category 4 storm. Papp, along with his wife, mother-in-law, two dogs, and cat, had evacuated from the Florida Keys when the storm was projected to hit Miami and head up the east coast. As he wrote in a Facebook post the night of the storm, “A change of plans and directions, and here we are on the west coast looking at a spaghetti trail leading right into the lobby of our hotel. ”
Unfortunately, this was a common experience for Florida residents when Hurricane Irma hit on that day. The unpredictable nature of hurricanes, and other natural disasters, makes preparation for these situations a difficult challenge.
The most costly hurricane season on record occurred in 2017, with damage exceeding $200 billion. It was also the most active hurricane season since 2012. “A total of 10 hurricanes swept the region. Six were major storms of Category 3 or higher, and three of those were Category 4 or higher when they made landfall, spreading havoc from the Caribbean to Texas,” NPR (National Public Radio) reported.
Rarely do architects, contractors, builders, and manufacturers have the structural integrity of our buildings tested the way it was in 2017. Weather patterns and the hurricanes they produce have always fluctuated in long cycles—very active periods, followed by long periods with mild hurricane seasons. While the number and intensity of storms vary over a period of years, scientists have reason to believe that, in the future, storms may be bigger and more intense. This can lead to increased destruction, particularly in low-lying regions.
Over the past 100 years, population density has increased along coastal areas. The desire to live and work in coastal climates isn’t likely to change, so it is critical to assess how commercial-building products, particularly impact products, stood up to the test in 2017 and what we can do differently moving forward.
Codes and Impact Products
Since the mid-to-late 90s, the objective of impact products has been to protect the building envelope from rapid internal pressurization. Hurricane Andrew changed the game in 2002, resulting in updated codes and changes in impact-product technology. In 2004, when Hurricanes Charley, Ivan, Frances, and Jeanne all hit the state of Florida, those updated codes and impact products were put to the test. But, it wasn’t until Hurricane Irma in 2017 that a storm truly challenged the strength of buildings built to comply with 2002 codes.
“If we look back at the past two decades, impact products have done an excellent job of protecting the building envelope from potentially detrimental consequences, like damage to or full loss of a building’s roof,” said Barry Wampler, Orlando, FL, branch manager for YKK AP America Inc., Austell, GA (ykkap.com). “During the 2004 active hurricane season there were minor instances in which aluminum materials were slightly overstressed but, on a whole, impact products continue to successfully perform.”
Water Still Intrudes
While building codes and impact-resistant products have successfully improved the structural integrity of buildings, an issue that continues to surface is water intrusion. Prior to 2002, water intrusion was not an issue if the building structure itself wasn’t able to survive high and sustaining winds. Now that buildings are built to meet and, in many cases, exceed codes, severe wind-driven rain and heavy flooding have become an increasing challenge.
The speed of a storm can determine the amount of rain a region will experience. In general, fast-moving storms produce less rain and resulting water damage. Hurricane Harvey, which made landfall near the towns of Rockport and Corpus Christi, TX, on Aug. 26, 2017, moved extremely slow over the course of four days and, as a result, caused widespread, unprecedented flooding and severe damage. According to The Weather Channel, rainfall topped out at 60.58 in. near Nederland, TX. Hurricane Irma, on the other hand, moved faster with higher sustained winds than Harvey, and the maximum rainfall topped off at 16 in. near Fort Pierce, FL.
Forensic research after the 2004 and 2005 hurricane seasons led to a greater understanding of severe wind-driven rain by 2010, but most of this knowledge has not yet been worked into the codes. Moreover, building activity continues to take place within FEMA’s (Federal Emergency Management Association, Washington) 100-year floodplain, and buildings that are built above or outside of the 100-year floodplain are still susceptible to flooding.
Windows and doors are critical to preventing water intrusion in a building. However, even when built to meet or exceed state building codes, water resistance is not guaranteed. According to the American Architectural Manufacturers Association (AAMA), Schaumburg, IL (aamanet.org), “In tropical storms and hurricane wind-driven rain conditions, the product selected to meet the state and local code requirements may still experience water leakage because these extraordinary conditions exceed the rated/code requirements for water penetration.” While improvements have been made to reduce water intrusion from wind-driven rain, it is prudent to get back into each building quickly after the storm to dry out the interior.
Danger from rising water due to storm surge or flooding, an issue separate from wind-driven rain, can also be difficult to prevent. Rising water is best controlled by elevating functional areas above predicted flood and wave-action levels or by building outside the floodplain. Existing buildings located inside or below the floodplain pose a dual challenge, especially in areas prone to flash flooding.
Entrance Design Crucial
Commercial entrances are particularly vulnerable to water intrusion. Typically, commercial entrances must meet Americans with Disabilities Act (ADA) Emergency Egress requirements, which ensure that there is an unobstructed entry/exit path to a structure. However, commercial entrances are exempt from water-test requirements, which can be problematic when dealing with severe-weather conditions. While a building may have been built to meet and even exceed strong hurricanes, such as Harvey and Irma, if the entrance is not taken into consideration in the project design and execution, water intrusion may still occur.
One way to better protect commercial entrances from water intrusion is to consider a roof or entrance overhang. Overhangs are well known for their energy-saving properties, as they effectively reduce solar-heat gain by providing additional shade. They can also keep wind-driven rain from entering entrances, windows, and the foundation of the building envelope, reducing overall water pressure.
The Cici and Hyatt Brown Museum of Art in Daytona Beach, FL, is a great example of this. The museum opened to the public in 2015 and serves as a sanctuary for local residents and a destination for visitors interested in exploring Florida history. RLF Architects, Orlando, FL (rlfarchitects.com) designed the building, which was built to resemble an old, rural Florida home and reflect the rich history of the artwork housed there.
Hurricane-resistance was a key component in the design process and impact-resistant products were used throughout the building. The YHS 50 TU impact-resistant storefront, YHC 300 OG impact-resistant curtain wall, and Model 35 H impact-resistant entrances, manufactured by YKK AP America Inc., were used on the building. An overhang was also integrated to add to the character of the building and provide additional protection from wind-driven rain. When Hurricane Irma hit in 2017, the museum served as a shelter for staff that needed to stay on property and those that weren’t able to leave town. Despite nearly 7 in. of rain, combined with 60-to-80-mph wind gusts, the building resisted flooding and damage.
Even overhangs may not be enough to prevent water intrusion from severe wind-driven rain during a hurricane. Another consideration when designing a building entrance is to use hard-surface floors and properly equip the interior of the entrance with strategically placed drains. Ideally this type of drainage will be coupled with an entrance awning or overhang for maximum protection.
In more-extreme situations, rising water from flash flooding or water pooling in low-lying areas is a life-safety concern for entrances and the surrounding fenestration. The rate-of-rise of floodwaters for an at-risk site needs to be determined and paired with adequate warning time to allow evacuation. Specialty flood doors may be used to hold back rising waters and keep the path of egress open for the required warning period.
Sound may not be the first thing to come to mind when thinking of a hurricane-resistant building, but one lesson Hurricane Irma taught us is it’s a wise consideration to keep in mind. When the Papp family sought refuge at the Hyatt House, what they didn’t know, but quickly came to appreciate, was that, in addition to the impact-resistant requirements of the building, stringent acoustical requirements were considered in its design.
While Hyatt House is in a vulnerable location due to its proximity to the coast, it is also in a noisy location, at the end of the Naples Airport runway. YKK AP designers worked closely with glazing contractor Mullet’s Aluminum Products Inc., Sarasota, FL (mullesaluminum.com) to ensure products were developed and installed to deliver the highest sound performance possible. Thermally broken impact-resistant fixed windows and thermally broken architectural terrace doors were used on the building’s facade to provide impact resistance.
Both products were then sealed with an interior secondary access-panel window system to enhance thermal, sound, and privacy performance. As Scott Papp watched Hurricane Irma roll in from his hotel room at Hyatt House Naples, he recalled, “We could see the storm raging, but it was very strange, we could barely hear it.” Acoustics can go a long way in enhancing occupant comfort and providing a feeling of safety and protection during severe weather conditions.
More Work Ahead
The International Building Code is now the base code for all states and is updated every three years to reflect new learning and knowledge. Likewise, the 6th Edition of the Florida Building Code became effective Dec. 31, 2017. Forensic research after an active hurricane season provides the best data on what past measures were successful and where more attention is needed. The 2017 hurricane season tested and proved that the industry’s efforts have been well worth it. However, there is still work that needs to be done.
Pre-2002 buildings did not hold up nearly as well during this past hurricane season and must also be retrofitted to withstand future storms and potential damage. Additionally, rising water from storm surge and short duration over-saturation are areas needing continued technological advancement. Whether it is due to global warming or simply because there is more building in coastal areas, rising water is a more of an issue now than in the past.
Since Hurricane Andrew hit in the ‘90s, the building industry has come a long way in recognizing that codes must evolve to better protect buildings themselves, major sources of property loss, and, most important, building occupants.
Greg Galloway is ProTek brand manager for YKK AP America Inc., Austell, GA (ykkap.com). An ASQ Certified Quality Engineer, his background includes 28 years in residential and commercial fenestration. For the past 14 years, he has been active in the design, building, and marketing of hurricane impact- and blast-mitigation products.