Wind Resistant New Jersey Architecture
New Jersey is a unique state, with one-third of its counties bordering either the Atlantic Ocean or one of the nine rivers in the state. The coastal zone lies along the Atlantic Ocean which moderates its temperature; it is subject to strong coastal storms (nor’easters) and at least one storm a year impacts the region. There are coastal areas where homes are between the ocean and a river, with winds generally sweeping through in a more dramatic way than those that just face a single body of water.
Architects and builders in New Jersey are increasingly tasked with creating appealing homes that are also able to stand up to nature’s whims.
The Insurance Institute for Business & Home Safety (IBHS)’s 2018 report assessing the residential building code systems in 18 hurricane-prone states ranked New Jersey the fourth highest amongst 18 Atlantic and
“What can and must stop is the continued construction, and inevitable destruction, of weak, vulnerable homes built – and too often rebuilt – in questionable locations,” said Julie Rochman, IBHS CEO and president. “We must build stronger, to code standards proven to reduce risk, and stop allowing today’s weather events to become painful, expensive disasters for homeowners, communities, states and the entire nation.”
New Jersey was severely impacted by Hurricane Sandy, one of the most intense storms of the century, with economic losses to businesses of up to $30 billion. Sandy made landfall on New Jersey on October 29, 2012. Over two million households in the state lost power in the storm, 346,000 homes were damaged or destroyed, and 37 people were killed. Dubbed a “superstorm” by weather forecasters, Sandy delivered a lethal brew of rain, wind and ocean storm surge to the coast, focusing its fury on the fragile barrier islands that sit two to seven miles offshore, in some places wiping all existing real estate off the map. On and near the shores of the Atlantic Ocean, Barnegat Bay and Little Egg Harbor, thousands of homes were inundated with seawater, in many cases damaged beyond repair. Storm surge and flooding affected a large swath of the state. Governor Chris Christie said the losses caused by Sandy were “going to be almost incalculable…The devastation on the Jersey Shore is probably going to be the worst we’ve ever seen.”
Design and Building Innovations
“More than ever before, building design and construction can be significantly improved to reduce wind pressures on building surfaces and to help better resist high winds and hurricanes in residential or commercial construction,” said NJIT architecture professor Rima Taher, PhD. Taher, who is also a civil/structural engineer, teaches at the New Jersey School of Architecture.
When it comes to wind-resistant construction, engineers tend to focus on the details: strong connections, tested components, and engineered elements, such as shear walls and diaphragms. But there’s also a benefit to stepping back and looking at the big picture of design. Certain building shapes, for example, are more advantageous in a high wind, and choosing those shapes can reduce the potential stress on the particular framing connections that hold the house together.
Professor Taher recommends the following for anyone building in high wind regions: “Design buildings with square, hexagonal or even octagonal floor plans. Such designs reduce wind loads.”
Roofs with multiple slopes such as a four-sloped hip roof perform better under wind forces than gable roofs with two slopes. Gable roofs are common only because they are cheaper to build. Research and testing show that a 30-degree roof slope has the best result in withstanding wind.
Wind forces on a roof tend to create uplift, which explains why roofs blow off during extreme wind events. To combat uplift, Taher advises connecting roofs to walls with nails, not staples. Stapled roofs were banned in Florida after Hurricane Andrew. Aim for strong connections between the structure and foundation. Structural failure is often progressive where the failure of one structural element triggers the failure of another. Connections can be inexpensively strengthened.
Roof overhangs are subject to wind uplift forces, which could trigger a roof failure. In the design of the hurricane-resistant home, the length of these overhangs should be limited to about 20 inches.
In a 2007 review article in the Journal of Architectural Engineering, Taher notes decades of research showing that hip roofs, for example, are better than gable roofs when a hurricane hits. Wind tunnel testing at France’s Center for Building Science and Technique (Centre Scientifique et Technique du Btiment or CSTB), found that a roof slope of 30 degrees experienced the lowest wind pressures under high-wind conditions.
The latest building codes and products reduce damage from flooding, wind damage and storm surge. Sound hurricane-resistant building basically addresses three problem areas: lift up from high winds, penetration from wind-blown debris and damage from rain and flood waters. These three best practices for building in a hurricane-prone area will help reduce damage to buildings during storms:
1) Tie It Down.
The current New Jersey codes require buildings in coastal areas to have a continuous load path that directs wind loads on the roof and walls down to the foundation. This has led to widespread use of tie-down straps, J-bolts, cable ties, expansion bolts, hurricane clips and plates.
2) Make It Impact Resistant
Reinforced, impact-resistant doors, laminated windows, storm-resistant windows or hurricane shutters, pull-down PVC shutter systems and high-impact synthetic window shades all contribute to a home’s impact resistance.
3) Keep It Dry
Sealants, waterproof membranes, house wrap, rainscreen systems and use of mold and mildew-resistant materials can keep rain and moisture out of the home or reduce resulting damage.
We have all heard the famous proverb: necessity is the mother of invention. Courses offered at the NJIT College of Architecture and Design include options like Environmental Control Systems, that educate students to take environmental threats into account in their design process. As architects’ awareness of our changing environmental reality increases, they are designing for a resilient future. It will be exciting to see the coming innovative home designs that reflect the increasing need for safety and protection from the elements, without sacrificing aesthetic appeal.