Sandcastle: The House That Can Survive 250-mph Winds

When John Pistorino set out to create the “Sandcastle,” a hurricane-resistant house in Islamorada, Florida, he knew it would need to withstand the high winds and storm surges of the hurricanes that plague the Florida Keys. Florida is the hurricane capital of the nation, and Islamorada has been home to several hurricanes since construction of the Sandcastle began in 1991, including Hurricane Andrew in 1992. Pistorino wanted Sandcastle, which sits 50 feet from the Atlantic Ocean, to withstand battering winds of up to 250mph. Serving as a consultant to FEMA, he had experience with hurricane damage control, building codes, and construction designs that were required for a challenge of this nature. Pistorino designed his home as a 3-story elevated structure with curved lines to deflect wind, a concrete frame, and round cast-in-place concrete support columns that would withstand hurricane-level storm surges. The support columns — rated to withstand 5,000 psi of pressure — extend down to bedrock and the foundation is drilled into hard coral rock, keeping it from being undermined and eroded by storm surge and waves. The bottom floor consists of breakaway walls. He also specified laminated, high-impact glass for the home’s windows and doors, along with 18-gauge solid steel protective shutters. Interior walls are a special form of drywall that won’t dissolve like gypsum-based drywall when saturated with water, and the home’s roof is a solid concrete slab with no shingles or other type of roof coverings. Pistorino’s design and construction strategy paid off when Category 4 Hurricane Irma hit the Keys in 2017. While most buildings in the area sustained heavy damage, Sandcastle stood up to the 120mph winds with no damage at all. All the sand below the house was scoured away down to the bedrock by the storm surge, but the house itself wasn’t impacted.