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<br />71 <br /> <br />-~ <br /> <br />VIII. CLOSURE OF OPENINGS <br /> <br />8.1 Introduction <br /> <br />Attention should be devoted to any doors, windowL vents, or other openings in a structure <br />that are below the 8FE. If an existing opening belo-J the BFE can be eliminated without mak- <br />ing the building less functional, it should be perman~ntlY closed. The permanent closure <br />should be completely impermeable and may requir~ added reinforcement. All other openings <br />below the BFE must be provided with some type oflclosure that can be put in place easily <br />when needed, This kind of temporary closure equiPfent is called a flood shield. Closures <br />must provide protection to one foot above the BFE,: <br /> <br />Closure of openings, as a flood proofing method, is imost applicable to structures that meet <br />certain criteria. First, the wall of the structure shoulej be brick, brick veneer, concrete, cement <br />block, stone, or other relatively impermeable mat,,,i~ls. The structure should have a small <br />number of openings, unless low outdoor walls are t~e flood proofing method to be used. <br />Another mandate is that the walls themselves have jhe structural strength to resist the water <br />forces up to the top of the closures. Finally, the stru!cture should have a sump pump that can <br />take care of seepage during the flood. ' <br /> <br />A comment on the availability of flood shields is inl order. Some custom sheet metal <br />businesses will make shields if given the proper drajNings and dimensions. Strength <br />requirements should be calculated for such shields. Ifhere is also at least one company that <br />specializes in flood shields and it is listed in the ac~nowledgements, Because flood shields <br />are custom designed and engineered for each applihtion, it is difficult to make any general <br />statements regarding prices. They may vary greatly ffom one manufacturer to another. <br /> <br />8.2 Material for Shields <br /> <br />Any durable material that can withstand the design! flood loads may be used. Aluminum is <br />often the best choice because it has the necessary *trength, is usually readily available, and <br />its relatively light weight permits easy and quick installation. Steel and exterior grade <br />plywood are other materials that are used. <br /> <br />8.3 Installation of Shields <br /> <br />I <br />Shields are usually attached to a metal frame for t 'e most reliable connection. The frame <br />must be capable of evenly transferring the panel 10 ding into the wall. If the frame brackets <br />are an appearance problem, it may be desirable to lave a removable trim covering for the <br />frame. Shields may be set on hinges, slide track roll, rs, or vertical pulley systems, Some cir- <br />cumstances may require that they be stored away f om where they will be used, <br /> <br />In order to assure complete watertightness, gasket~ or other types of seals must be used <br />between contact surfaces of the shield and frame, Seals should be of the pressure type and <br />permanently attached to either the frame or the shi~ld, Inflatable seals are available through <br />some manufacturers. <br /> <br />Another consideration is the type of latching de\lic~' to be used on the shield. Standard <br />bolts, T-bolts, latching dogs, wedge assemblies, or other means may be used. Whichever fas- <br />tener requires the minimum time effort and skill is (he best choice. <br />i <br /> <br />Whether the shield is put on the outside or inside!will depend on the user and each situa. <br />tion. The advantage of putting the shield on the OU\Side is that the water pressure will help <br />create a tighter seal between the shield and frame 10 which it is attached. On the other <br />hand, a shield on the inside will probably be more t1ccessible for placement and correction <br />of any problems, <br />