This article was originally featured on our sister site BUILDER.
After repairing damage to their waterfront home from Hurricane Irene in 2011, a Southhampton, N.Y., couple was devastated when Superstorm Sandy’s strong winds and storm surge came along one year later and left their 1940s cottage on Shinnecock Bay unlivable for a second time.
They decided to rebuild using resilient and sustainable techniques that would ensure that their new home would never meet the same fate. Designed by local architect Bill Heine and built by Westhampton Beach, N.Y.-based Coastal Management, their new 3,600-square-feet LEED-Platinum beach house was completed in 2015. The state-of-the-art home was the first to register to take advantage of Southhampton’s new property tax exemption for LEED-certified homes, says the home’s sustainability consultant, Kim Erle of Sunset Green Home.
Here, Erle talks with BUILDER about the products and technologies that make the home storm resistant and resilient.
Tell us about the house’s history with coastal storms.
The original home was built in the mid 1940s, less than a decade after the devastating Hurricane of 1938. It stood at five feet above sea level for close to 70 years. The home suffered some damage in Hurricane Irene in the late summer of 2011 and had to be rewired following the storm. Following Superstorm Sandy in October 2012, the house was declared "substantially damaged" which meant that it would have to be rebuilt to comply with current building codes.
Did the homeowner think about not rebuilding?
Choosing not to rebuild wasn't an option because from an economic perspective, abandoning the property didn't make sense. Current building codes required the home to be elevated to 12 feet above sea level, a full 4 feet above the maximum storm surge level from Superstorm Sandy. In fact, the design/build team elected to go 2 feet higher and build the home at an elevation of 14 feet. The team felt this would offer considerable protection against future flood events.
How did you rebuild with resiliency in mind?
We incorporated a variety of resiliency measures into the home's design. The house is built on top of pilings, with breakaway walls underneath. This design would enable flood waters to pass under the house and recede back without causing structural damage to the house itself. Impact-resistant glass protects the home from wind-borne debris.
Our resiliency measures went well beyond storm-resistant construction. The framing of the home was sprayed with FortiCel, a topical application that inhibits the growth of mold and mildew on structural framing surfaces. The wall assembly is protected from damaging effects of trapped moisture with home is protected from damage by mold and mildew by Smartbatt, a fiberglass insulation with a smart vapor retarder, which allows the walls to "breathe" when humidity is high. Landscaping was kept at least 2 feet from the foundation, and wood-to-concrete connections were avoided to minimize the likelihood of damage from pests. For more information about our building techniques, see our blog.
What should builders keep in mind when building homes in storm-prone areas?
Building codes will dictate the minimum requirements to protect the home against wind and flood - including building elevation and hurricane strapping. But builders should think through the measures that might protect the home against the damaging effects of wind and moisture that go beyond simple code compliance. When owners can afford it, builders may want to incorporate impact-resistant glass. If budget doesn't permit specialty glazing, architects and/or builders should consider alternative strategies like hurricane shutters to protect the building envelope from wind-borne debris. Likewise, builders should consider strategies to keep moisture out of the walls and to dry the walls if moisture should find its way inside.
So the home is energy efficient and hurricane proof?
Absolutely! Hurricane resistance starts with well-designed and code-compliant hurricane strapping to create a continuous load path designed to enable the building to withstand hurricane-force winds. Continuous sheathing creates an airtight and water tight shell, which protects the structure from strong winds and driving rain. As a secondary benefit, an airtight envelope is a critical element in the home's drive to be energy efficient. Lastly, impact-resistant windows protect the home from wind-borne debris. And by installing impact-resistant windows, we eliminate the need to install plywood during a major wind event - and that further protects the building envelope integrity and supports the energy efficiency of the home. See our blog at http://www.sunsetgreenhome.com/blog/2014/10/2/wind-resistant-building#
What types of resilient products did you use?
--Zip System Sheathing created an airtight and watertight shell
--AdvanTech subflooring resists warping and other effects of moisture
--FortiCel inhibits the growth of mold and mildew on internal framing members
--Smartbatt insulation with integrated smart vapor retarder allows the walls to "breathe" and prevents moisture from being trapped inside
--Atas aluminum standing seam roofing resists the effects of a coastal environment, and provides an ideal surface for solar PV panel installation without any roof penetration
--Pilings under the home raise it above the base flood elevation and allow water to pass under during a flood event
--Integrity Wood Ultrex windows with impact-resistant glass protect against windborne debris
--Ventgrid 12 forms a drainage plane behind the roof shingles and acts as an air gap to control against heat-related roof degradation such as splitting, cracking, curling, warping, and cupping that create openings for water to get behind the roof shingles