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[0001]    This is a continuation-in-part of International Application PCT/GB01/04897, with an international filing date of Nov. 2, 2001, published in English under PCT Article 21(2) as International Publication Number WO 02/40818 A1. 
     
    
     
       BACKGROUND TO THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates to a flood protection barrier. In particular, it relates to a flood protection barrier that can be installed to protect premises from an imminent flood risk.  
           [0004]    As is well known, rising floodwater can cause extensive damage to the fabric and content of a building with alarming rapidity. Heavy rain and/or high tides can cause rivers to burst their banks and inundate a large area.  
           [0005]    Traditionally, there has been little contingency action available to premises owners other than building a defensive barrier of sand bags. Sand bags can act as a reasonably effective filter to remove mud from floodwater. However, these are inconvenient, require a large amount of time and labour to install, can be used only once and, most particularly, they do not act as a good barrier to water entering premises.  
           [0006]    2. Summary of the Prior Art  
           [0007]    There have been various proposals for barriers to prevent floodwater from entering premises through a door or window opening. However, these typically require permanent installation of fittings (such as mounting channels) to the building in the region of the doorway to which a removable barrier can be connected in use. While such barriers can provide an effective flood defence, many occupiers do not wish to have permanent fixtures mounted on their premises. These fixtures may detract from the appearance of their premises or be otherwise inconvenient on a permanent basis, while they are needed for use only in the event of a flood; an event that may happen only once in many years. It is also apparent that many of these known devices might be subject to theft or tampering whilst in use.  
           [0008]    An aim of this invention is to provide a flood protection barrier for a door or other aperture in a building that can be deployed rapidly as and when required, yet leave no (or minimal) fixtures in place while the barrier is not required for use in times of normal weather.  
           [0009]    Accordingly, from a first aspect, the invention provides a flood protection barrier that comprises a shield having a sealing element and securing means for securing the shield in place to at least partially close a door or window aperture in a wall of a building, the aperture having a door or window frame; in which: the securing means cooperates with a surface of the building at the periphery of the aperture or the frame, and the sealing element forms a fluid-resistant seal between the barrier the frame at the periphery of the aperture.  
           [0010]    Such a barrier can be deployed as and when required to protect against an imminent flood risk.  
           [0011]    Advantageously the securing means is carried on the shield. More specifically, the securing means may be entirely carried on the shield. This has a twofold advantage, in that no part of the securing means is left in position on a building when the barrier is not in use, and in that the securing means are unlikely to be misplaced; this being especially important because they may be required for use as a matter of urgency.  
           [0012]    For example, it may be adapted to cooperate with the frame. Advantageously, the securing means may be configured to be accessible only from within a building that the barrier is deployed to protect.  
           [0013]    This reduces the likelihood that the securing means will be subject to unauthorised tampering. It is advantageous that the barrier, when deployed, does not prevent closure of the door or window. This may be achieved by providing securing means that cooperate with an outer part of the frame or the reveal adjacent to the frame. Alternatively, in the case of embodiments according to the last-preceding paragraph, the securing means may cooperate with an inwardly directed surface in the region of a recess into which the door or window (as the case may be) is received when closed. Provided that the securing means is suitably dimensioned (i.e. thin enough) it will not prevent closure of the door or window, thereby ensuring that the building upon which the barrier is deployed can be secured.  
           [0014]    Typically, the securing means includes a plurality of clip means. Each clip means can be deployed to secure the shield to a formation of the frame. Each clip means may be adjustable to enable it to be secured to a range of different frames. For example, it may include two mutually adjustable components, one of which is fixed in relation to the shield.  
           [0015]    Most typically, the shield is made of a rigid material, such as suitable plastic, wood or composite material. The shield must have sufficient rigidity to resist pressure of water that it is likely to encounter while distorting by no more than an acceptable amount. The shield may have a generally flat face (or a flat peripheral region of a face) that engages with the periphery of the aperture. An opposite face of the shield may be provided with strengthening formations.  
           [0016]    Each shield is advantageously formed with a dimension that is greater than a corresponding dimension of the aperture. Such a shield may be placed against an external surface of the aperture, such that water in contact with the shield acts to push the shield into engagement with the external surface, and thereby assist in locating it in place.  
           [0017]    The sealing element may include an elongate flexible plastic material element. A portion of sealing element may extend along part of a flat surface of the shield. Such a portion of the sealing element may engage, in use, with a face portion of a frame (such as a door or window frame) of the aperture. A further portion of the sealing element may extend along part of a peripheral surface of the shield. Such a further portion may engage with a sill or step portion of a frame of the aperture. In addition, such a further portion may engage with a portion of another barrier, for example, such that a plurality of such barriers can be stacked one upon the other in order that a user can select the height of a barrier to be deployed. (That is to say, several such barriers may be placed one on top of another to form a barrier of greater total height.)  
           [0018]    From a second aspect, the invention provides a flood barrier assembly comprising a plurality of flood barriers, each according to any preceding claim, disposed adjacent to one another to form a water resistant barrier assembly for an aperture in a wall. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]    [0019]FIG. 1 is a perspective view of a flood barrier being a first embodiment of the invention, in position within a door recess, viewed from outside of a building;  
         [0020]    [0020]FIG. 2 illustrates a securing means being a component of the flood barrier of FIG. 1; and  
         [0021]    [0021]FIG. 3 is a perspective view of a flood barrier being a second embodiment of the invention, in position within a door recess, viewed from within a building. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    With reference first to FIG. 1, there is shown a flood protection barrier  10  being a first embodiment of the invention. This embodiment is intended to resist floodwater entering a building through a door aperture  12  formed in a wall  14  of the building.  
         [0023]    The barrier  10  includes a shield  20 . The shield  20  includes a generally rectangular plate member  22  formed of a stiff, water-resistant material such as a tough polymer, a composite (e.g. glass-reinforced plastic) or suitably treated timber sheet.  
         [0024]    One side of the plate member  22  (disposed to face into the door aperture, as shown in FIG. 1) is generally flat, and carries sealing elements, to be described below. The opposite side of the plate member (disposed to face out from the door aperture, as shown in FIG. 1) is formed with a plurality of strengthening ribs  24 , arranged, in this embodiment, in a grid disposition. As will be understood, strengthening may be included on the plate member  22  as required to impart the shield  20  with sufficient stiffness. This will differ from one embodiment to another. The strengthening ribs (or other elements) may be formed integrally with the plate member or may be separate components applied to it. Upper and lower flanges  26 ,  28  project from upper and lower edge regions of the plate member  22 .  
         [0025]    The shield  20  is installed with the plate member  22  against upright members  30  of a frame of the door aperture  12 . The lower flange  28  is supported upon a sill member  32  of the frame  30 .  
         [0026]    Elongate sealing elements (not shown) are applied to the shield  20  that form a water-resistant seal between the shield  20  and members  30 , 33  of the frame. Typically, the sealing elements are carried on the plate member to seal against upright members  30  of the frame and on the lower flange  28  to seal against the sill member  32 . In alternative frame structures (typically used in aluminium or uPVC doors) there is an upright member extending up form the sill  32  against which sealing elements may seal.  
         [0027]    The sealing elements can be formed as elongate extrusions of flexible plastic material, such as foam plastic or natural or synthetic rubber. These extrusions are secured to the shield  20  by adhesive. The sealing elements may be applied to the shield  20  during its manufacture, or they may be supplied separately for application upon deployment of the barrier.  
         [0028]    With reference now to FIGS. 1 and 2, a system by means of which the barrier  10  is retained in place within a doorframe will now be described.  
         [0029]    The barrier  10  is provided with a plurality (in this case, four) wedge elements  40 . Each of these is tethered to the barrier  10  by a length of flexible rope or wire  42  in order that they will not become separated from the barrier  10 .  
         [0030]    Each wedge element  40  includes a wedge-shaped body within a sloping surface of which is formed a groove  44 . In order to secure the barrier  10  in place, the wedges are driven between the barrier  10  and the periphery of the aperture into which the barrier is to be located.  
         [0031]    In order to deploy the barrier  10 , the shield  20  is placed against the outside of the frame with its sealing elements in contact with members of the frame. The sealing elements therefore form a seal with outwardly-directed elements of the frame. The wedge elements  40  are then driven between the shield and the reveal surrounding the frame to retain the barrier in position against the frame. Each wedge element  40  is located such that an end portion of one of the ribs  24  is located within the groove  44 . This assists in retaining the wedge elements  40  in place.  
         [0032]    An alternative embodiment of the invention will now be described with reference to FIG. 3.  
         [0033]    The barrier  50  of this embodiment of the invention includes a shield  52  that is of substantially the same construction as the shield  20  of the first embodiment. Likewise, the shield  52  carries sealing elements that can form a seal between the shield and a door or window frame.  
         [0034]    In this embodiment, the barrier is retained in position on the frame by a plurality of (in this case, four) clip assemblies  54 . Within the scope of this invention, a large variety of clip assembly structures could be employed, and it should be understood that the clip assembly described is just one of many possibilities.  
         [0035]    Each clip assembly  54  includes a first component  56  that is secured to the shield  52 , for by a fastener such as a nut  58 . A second component  60  is adjustably attached to the first component  56  by a fastener such as a nut  62 . The second component  60  of the clip assembly  54  is shaped to engage with a formation  64  of the frame. The formation with which the clip cooperates is formed by the recess into which the door or window (as the case may be) is received when closed.  
         [0036]    In order to deploy the barrier  50 , the shield  52  is placed against the outside of the frame with its sealing elements in contact with members of the frame. The second component  60  of the clip assembly  54  is then brought into engagement with the recess  64  of the frame. The shield  52  is pushed into contact with the frame, and the second component  60  is pushed against a surface  66  within the recess  64  that faces into the building, and the nut  62  is then tightened. This is then repeated for all four clip assemblies. The second component  60  is sufficiently thin that it can fit between the door or window (shown in ghost lines at  68 ) and the frame, thus allowing the door or window to be closed while the barrier is deployed.  
         [0037]    As can be seen in FIG. 3, access to the clip assemblies can be gained only from within the building, such that they cannot be dislodged by floating articles or deliberately tampered with from outside of the building. Moreover, the presence of the clip assemblies does not prevent the door or window being closed while the barrier is deployed.  
         [0038]    As will be understood, the barrier  50  is retained in place by the clip assemblies  54 . The presence of the sealing elements resists or prevents ingress of water through the aperture. (This applies to both of the described embodiments.) In the event of water rising to the outside of the building, the water pushes against the shield and urges its sealing elements into closer contact with the frame, thereby enhancing their ability to provide a watertight seal.  
         [0039]    In the event that there is a risk that floodwater will rise above the height of the shield  52 , a further shield may be installed above a first shield such that the shields are stacked one upon another within the door or window opening. To enhance the security of such a configuration, the shields  52  may be interconnected by fasteners (for example, nuts and bolts) inserted through suitably placed holes  66  in adjacent horizontally extending members of the shields.

Summary:
A flood protection barrier is disclosed that can be deployed in the event of an immanent flood risk. The barrier comprises a shield having a sealing element and securing means for securing the shield in place to at least partially close an aperture in a wall of a building. The sealing element forms a fluid-resistant seal between barrier and the periphery of the aperture thereby resisting passage of water through the aperture. The barrier can be secured by securing means that require no modification to the building. The securing means may include clip assemblies or, in alternative embodiments, wedges or other suitable components.