As most Long Island and New York homeowners are still waiting for insurance settlements to rebuild after Superstorm Sandy (see this Newsday article), it is imperative that planning for future storms be taken into consideration. Once settlements have been made, it is prudent to avoid the mistakes that were made previously that caused the loss of mechanical and HVAC equipment to flood waters. Of the many homes and businesses we have inspected that experienced damaged HVAC equipment, most were within the flood zone, but still had mechanicals located at ground level or sub-grade in basements. Although this may be standard policy for those residing inland, it can no longer be the norm for those who have decided to live within or near flood zones. Those who are merely replacing what they had in the same locations are asking to go through these losses all over again. This financial burden will continue to be borne by both homeowner and taxpayer until proper disaster planning and construction standards are required in all FEMA flood zones.
FEMA has a Coastal Construction Manual with guidelines for installing mechanical equipment and utilities. FEMA warns that “Minimizing flood damage to mechanical equipment requires elevating it above the DFE. Because of the uncertainty of wave heights and the probability of wave run-up, the designer should consider additional elevation above the DFE for this equipment.” DFE refers to the design flood elevation. Condensing units should be installed on cantilevered platforms above the DFE with restraints to prevent wind damage. Ductwork should not be located in sub-grade crawlspaces or basements and should be installed above the DFE or be made watertight in order to minimize damage. “Many ductwork systems today are constructed with insulated board, which is destroyed by flood inundation.”
Interior HVAC equipment including boilers, furnaces and air handlers should also be located above the DFE. The following methods of reducing flood damage to interior equipment are recommended:
“Elevate the equipment and the ductwork above the DFE by hanging the equipment from the existing first floor or placing it in the attic or another location above the DFE. In areas other than Zone V (where enclosure of utilities below the BFE is not recommended), build a waterproof enclosure around the equipment, allowing access for maintenance and replacement of equipment parts.”
Coastal homes on barrier islands in South Carolina, Georgia and Florida have been built this way for sometime and continue to endure hurricanes. It is obviously time for Long Islanders and New Yorkers to follow suit in the wake of accelarating global climate anomalies.