Withstanding the storm

 Five years ago, Hurricane Ivan tore through Cayman and left in its wake a devastated vista of wrecked homes and shattered buildings.

Despite Cayman’s relatively strict building code, the island’s properties could not withstand the huge sea surges and the flooding that Ivan brought with it.

More than 13,500 homes, or 83 per cent of dwellings in Grand Cayman, suffered some level of damage in the massive storm. As a result, Ivan has coloured the way architects and designers approach the creation of new homes in Cayman.

A drive along South Sound, an area that suffered major surge during the September 2004 storm, reveals how some are taking dramatic steps to make their houses as hurricane-resistant as possible. Across the street from one another stand two partially-constructed houses on high stilts.

“This is the future of Cayman-style houses,” said Lindsay Scott, owner of LAS Development, who is constructing the house on the waterfront side of the road and who also built the similarly elevated Frank Ebanks house, also in South Sound.

“It’s ridiculous for people to build houses on the ground in this area. Everything in South Sound should be elevated. The waves can reach 8-10 feet there, that’s why I built the house 17 feet above sea level.”

To elevate the house, Scott had a running battle with the Planning Department for several months. The house is about 60 feet above sea level at its highest point – a tower that he eventually received permission to erect. According to the Development and Planning Law, a residential building should be a maximum of 33 feet high.

“The planning law discourages elevated houses. That law needs to be rewritten,” said Scott, who showed photos of homes in South Sound destroyed in Ivan at a planning board appeal as evidence of what can happen to non-elevated houses in that area.

Hurricane- and earthquake-resistant, the house rests on 42 steel-reinforced concrete columns that are 20 inches thick and are piled nine to 12 feet into the bedrock below.

It can withstand winds of 200 miles per hour. The walls of the house, made of insulated concrete form blocks, can withstand wind speeds of 325 miles per hour. A parking garage is situated underneath the house, but otherwise it is entirely open, so in strong surge, the water will crash underneath the house.

People building new homes throughout Cayman are trying to ensure that if a catastrophic storm hits again, they will be prepared to sit out the aftermath in more comfort than they did in Ivan, when power was lost in parts of the island for months.

Garth Arch, president of the Cayman Society of Architects, Surveyors and Engineers, explained: “Since Ivan, people are more interested in using standby generators, having cisterns, installing doors and windows that are hurricane-proof or impact-resistant,” he said.

He added: “Mainly what has changed, I think, is houses, near the water especially, are being built on elevations. The ground floor is becoming more of a sacrificed space, with people turning them into garages or drives.”

Scott Gossen of architectural and interior design company DDL Studio agrees. “Most people in Cayman have seen the infamous flood map produced after Hurricane Ivan illustrating flood levels across the island. The construction community and the clients we serve have subsequently incorporated elevated ground floor slabs above the flood plane to protect not only the structure and contents, but the occupants against future storms.”

He explained that roof designs have also changed dramatically since Ivan. “Cayman has almost universally adopted pre-manufactured roof trusses and the utilisation of hurricane straps to combat roof lift under the extreme forces generated by a storm.

“New resilient products have been added to protect the roof trusses like ice and water shield coupled with tighter nailing patterns on the roof sheathing. The building community has moved away from shingles and has turned to more resistant products with the preferred choice being standing seam roof sheeting,” he said.

Other new elements introduced since Ivan have been sea walls at sea-frontage properties and hurricane bunkers within homes where people can seek shelter.

“We’re also seeing people  reserving areas of their home that are isolated for post-hurricane living, with water, electricity and the basic comforts,” said Arch.

He said he would recommend that any building should be at least eight feet above sea level, and higher depending on its proximity to the coast

New developments that have been built higher are Rainbow Realty’s Savannah Grand homes (14 to 25 feet above sea level) and its Northward “Wildfiddle” development (12 to 15 feet above sea level).

“Although it’s always possible to construct homes high, even in swampy or low-lying areas of the island, having high land from the outset allows us to fore-go the expensive exercise of land filling or piling-style construction,” said Rainbow Realty’s Stephen Hislop.

He said the company took all the lessons learned in Ivan and applied them to its Savannah Grand project, installing impact windows, impact sliding doors, ‘standing seam’ roofs, truss roof framing, Hardi-Board soffits, and hurricane-rated front doors.

As more people build homes at higher levels and put down extra fill to elevate structures, there are concerns about water dispersal problems. In bids to ensure they avoid flooding, some home owners are causing their neighbours yards and roads to flood.

Architect Burns Conolly said: “The biggest change made by most people [since Ivan] was to elevate their buildings and sites… the bigger issue there down [the] line is that the neighbours and road system will be increasingly flooded.”

Despite the massive damage caused to buildings in Cayman, no changes have been made to the Building Code or the Development and Planning Law.

Haroon Pandohie, assistant director of planning, said the Building Code, written in 1999, has existing regulations to ensure homes could withstand hurricanes.

“The Building Code, in regards to hurricanes, is quite strict to start with. A lot of the houses that were damaged in Ivan were older buildings that were constructed pre-1999 Building Code. Building constructed according to the code withstood fairly well.

“Obviously, storm surge was not something the Building Code was looking at dealing with. It’s more geared towards hurricane winds and ensuring structures remain intact,” Pandohie said.

Even the strongest, most resilient house is still only as weak as its weakest link. As Lindsey Scott says of the South Sound home he is building, “It’s truly a well thought-out hurricane-resistant home. I’d never say it’s hurricane-proof though. Nothing is hurricane-proof.”

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