(Continued from page one) 



members, by using the right type of wall section that 

 we could harden these structures and decrease their 

 vulnerability to the storms." 



With Sea Grant funding, Machemehl is developing 

 minimum foundation, roof and framework stand- 

 ards that will enable coastal builders to construct 

 more storm resistant houses. Eventually Machemehl 

 plans to compile his findings into a model building 

 code which he will present to state officials. 



Machemehl believes that a properly designed 

 house, using the guidelines listed on page one, could 

 stand for 100 years. Today most coastal structures do 

 well to last 30 to 40 years, he says. Some even es- 

 timate average life at only 25 years. Machemehl and 



others believe that the keys to safety are getting the 

 house above storm waters, presenting minimum 

 resistance to those waters, and making the house one 

 solid unit to resist destructive forces. 



Coastal storms subject buildings to basically four 

 types of damage. The most destructive force 

 generated by a hurricane is usually the storm surge. 

 The surge is a mound of water pushed up ahead of a 

 hurricane advancing inland from the water. Ac- 

 cording to Machemehl, the surge causes the greatest 

 property damage and loss of life. Nine out of 10 peo- 

 ple who die during a hurricane are drowned by the 

 storm surge. 



Another major destructive force is flooding both 

 from heightened ocean level and from the torrential 

 rains that accompany hurricanes. Taken together, 

 storm surge and flooding cause structural and foun- 

 dation failures, says Machemehl. 



Then come the winds. Minor damage such as 

 broken windows can be expected with winds of about 

 50 miles per hour. Major structural damage begins to 

 occur when winds exceed 100 miles per hour. If a roof 

 goes, as is often the case in high winds, then walls are 

 also subject to collapse and the entire structure is 

 jeopardized. 



Finally, erosion results from a combination of 

 surge, winds and flooding. Beach structures are often 

 undermined during severe beach erosion, weakening 

 foundations and other structural supports, according 

 to Machemehl. 



The most severe damage to buildings in the coastal 

 zone results from foundation failures, Machemehl 

 reports. Next in severity is roof failures, normally 

 caused by inadequate ties between the structure and 

 the roof. The least severe damage, but largest in 

 terms of monetary loss, involves failure of siding, 

 broken windows, loss of porches and garages. 



A major shortcoming of present construction, 

 Machemehl contends, is that pilings are not placed 

 deeply enough. The North Carolina Residential 

 Building Code appendix on coastal construction 

 specifies that pilings be placed at a depth of eight feet 

 below the natural grade of the lot. But Machemehl 

 says that often isn't deep enough. Erosion can under- 

 mine pilings, leaving the house vulnerable to wind 

 and waves. 



In addition, Machemehl believes more attention 

 should be paid to the joints and connectors which 

 make a beach house one unit. Though the state code 

 Appendix D requires both in coastal construction, he 

 says more precise specifications are needed. When 

 lumber is connected properly with pieces of steel 

 rather than with nails, the structure can withstand 

 more force. 



According to Machemehl, the most dangerous 

 structures are prefabricated buildings and trailers, 

 structures placed directly on the ground rather than 

 on pilings (they float), and buildings which are not 

 tied down with metal connectors. 



The dangers 



North Carolina's coast feels the brunt of both 

 frequent Northeasters and hurricanes. 



Considerable beach erosion, winds and waters 

 damage property during Northeasters. The Ash 

 Wednesday storm, the most severe in recent 

 memory, caused more erosion on the coast from 

 Hatteras northward than any previously known 

 storm. It opened an inlet 200 feet wide on Hat- 

 teras Island and destroyed acres of protected 

 dunes. Miles of highways were either washed 

 out or buried in sand. Beach homes by the hun- 

 dreds were destroyed or damaged. 



A hurricane the force of Hazel is likely to 

 strike once every 100 years. An example of the 

 destructiveness of coastal hurricanes is a 

 National Weather Service report on Hazel, 

 which made landfall in South Carolina on Oct. 

 15, 1954: 



"Wind-driven tides devastated the immediate 

 ocean front from the South Carolina line to 

 Cape Lookout. All traces of civilization on that 

 portion of the immediate waterfront between 

 the state line and Cape Fear were practically 

 annihilated. Grass-covered dune some 10 to 20 

 feet high along and behind which beach houses 

 had been built in a continuous line five miles 

 long simply disappeared, dunes, houses and all. 

 The paved roadway along which the houses 

 were built was partially washed away, partially 

 buried beneath several feet of sand. . . . 



"Of the 357 buildings which existed on Long 

 Beach, 352 were totally destroyed and the other 

 five damaged. Similar conditions prevail on 

 Holden Beach, Ocean Isle, Robinson Beach and 

 Colonial Beach. In most cases it is impossible to 

 tell where the buildings stood. Where grassy 

 dunes stood, there is now only flat, white, sandy 

 beach." 



