Patent Publication Number: US-2011067339-A1

Title: Slate retainer and method of replacing broken slates

Description:
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to a slate retainer and in particular, although not exclusively, to a slate retainer for replacing broken slates and a method thereof. 
     It is extremely common for pitched roofs to be covered in slates or tiles to provide weather proofing. It should be noted that the term slate is used herein to refer to any natural or synthetic slates or tiles used as roof coverings. Conventionally, when covering a new roof or completely replacing an existing roof covering, each slate is drilled with two holes and held in place by driving nails through the holes into target areas of a roof. 
     One known technique is to use batons as target areas. Consequently, as illustrated in  FIG. 1 , roof batons consisting of wooden strips are first secured to the roof. The roof batons are arranged to run across the roof in continuous parallel lines that are generally substantially horizontal. The slates are then added in rows working from the bottom upwards. Each slate is arranged so that an uppermost edge is located on a first free baton (herein the respective head baton). The slate is nailed to a baton immediately below the respective head baton (herein the respective fixing baton) with the nails generally locating slightly above an uppermost edge of an underlying slate. A lowermost edge of the slate being secured, extends beyond a baton immediately below the underlying slates respective fixing baton thereby concealing the nail heads holding the underlying slate in place. The process is continued, working up the roof, until the roof is covered. Consequently, a durable and long lasting weatherproof covering is provided. 
     As an alternative to conventional batoned roofs, it is also known to cover the roof with boards of wooden sheets. On so called boarded roofs, the boards form much larger target areas than the batons. Moreover, the head of a slate rests on an area of the board spaced from the target area rather than a respective head baton. 
     In use, the slates are prone to damage and require replacement. Where only a small number require replacement, it is not practical to remove all higher levels. In this case it is known to use a tool referred to as a “ripper”. The ripper is a flat tool that is slightly thinner than the slates and includes a hooked portion. Thus the ripper can be used to remove the broken slate from the roof and the hooked portion can be used to rip the nails that previously held the broken slates in place from the roof. This can be done without affecting the surrounding slates. It is known to then slide a replacement slate upwardly into position and secure it in place using a strip of lead. For example, the strip of lead is nailed to a fixing baton of the underlying slates before a replacement slate is slid upwardly into position and the strip of lead subsequently bent to form a hook around the replacement slate. However, lead strips are prone to failing over time. Consequently, it is also know to secure the replacement slate in place using a slate retainer. 
     For instance, GB 2 228 502 discloses a two-part slate retainer comprising a fixing member that is secured to the respective fixing baton of the row of underlying slates, and a slate retaining member. The fixing member and slate retaining member are separate and arranged to slidably engage. Here the replacement slate is slid into position when the fixing means is secured. The slate retaining member is then slid into position, at which point the fixing member locks the slate retaining member relative thereto. 
     Know slate retainers can be unsightly. Furthermore, two part slate retainers can be fiddly to assemble, particularly given that roofers often wear gloves for protection from the cold. 
     It is an aim of the present invention to attempt to solve the above or other disadvantages. It is a further aim to provide a slate retainer for replacing broken slates that are less visible during use. It is a further aim of the present invention to provide a slate retainer and method of replacing broken slates that is easy and quick. 
     According to the present invention there is provided a method of replacing a slate and a single-piece slate retainer as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows. 
     According to an exemplary embodiment, there is provided a method of replacing a slate, without affecting the surrounding slates. The method comprises removing the slate. Once removed generally tops of two underlying slates are uncovered. Thus, a target area for a slate fixing of the underlying slates is visible between the abutment of the sides of the two underlying slates. The method comprises securing a first portion of a slate retainer to the target area visible between two underlying slates. Once attached, a replacement slate can be slid upwardly along the underlying slates into position. This is made possible by causing a second portion of the slate retainer to resiliently flex between the two underlying slates when the replacement slate is slid into position. Once the replacement slate is in position, the second portion can flex back in order to retain the replacement slate in position relative to the target area using a second portion of the slate retainer. 
     According to an exemplary embodiment, there is provided a single-piece slate retainer for use in the method of replacing a slate as previously described. Here the slate retainer includes a first portion that is securable to a target area of a roof. Suitably, the target area is a respective fixing baton of underlying slates. Here the baton is visible between the abutment of the sides of two underlying slates. Alternatively, the target area is a board of a boarded roof. The slate retainer also includes a second portion for holding a slate in position on a roof relative to the first portion. The first portion and second portion are separated by an integral middle portion. The middle portion is resilient so that the second portion is resiliently flexible relative to the first portion so that, in use, the second portion is flexible between two underlying slates. 
     Advantageously, because the second portion flexes downwardly between the two underlying slates, the second portion does not interfere with the replacement slate. Consequently, a head of the replacement slate is able to correctly locate on its respective head baton or part of the board of a boarded roof. 
     Preferably, at least a portion of the slate retainer comprises an anchor portion. Here, the anchor portion is arranged above the two underlying slates. The anchor portion is sized so as to extend, relative to an elongate axis of said batons, a greater extent than the gap between the underlying slates so that the anchor portion can not flex between the two underlying slates. Advantageously, the anchor portion improves the resilience of the second part and enables the middle and second portions to be offered at an improved orientation. Suitably, the anchor portion is spaced from the first portion. Suitably, the anchor portion is spaced from the second portion. For instance, the anchor portion may form part of the middle portion. 
     In one exemplary embodiment, the integral middle portion is also able to resiliently extend to locate the second portion further from the first portion. Thus, the method comprises causing the second portion to resiliently move away from the first portion. Here the middle portion may comprise one or more loops. The middle portion may be arranged to locate the second portion above the desired location of a foot of the replacement slate. Advantageously, this allows the slate retainer, to retain the replacement slate in a pre-tensioned state. For example, the slate retainer, in the pretensioned state acts to urge the replacement slate upwardly with respect to the roof. Here, the second portion may comprise a hook. Advantageously, a hook provides better support to the replacement slate. 
     In an exemplary embodiment the first portion includes at least one fixing location for receiving a fixing, such as a nail, in order for the first portion to be secured to the respective fixing baton of the underlying slates or secured to the board of a boarded roof. Suitably, the fixing location is an aperture. Preferably however, it is advantageous to provide at least two fixing locations, particularly when fixing to batoned roofs. Here, each fixing location is arranged so as to be spaced from the second portion a desired distance to accommodate two or more standard baton spacing distances. Thus, one slate retainer can be used to repair roofs having different baton spacings. Alternatively, a number of slate retainers can be designed, each suitable for a specific baton spacing. It will be appreciated that the location of the fixing location is not as critical for boarded roofs as the target area is larger. 
     In an exemplary embodiment, the slate retainer includes a locating portion. The locating portion is arranged, in use, to locate between the two underlying slates when the first part is secured to the target area. Thus, advantageously, the locating portion enables the slate retainer to be quickly and repeatedly positioned and aligned in place. Suitably, the locating portion is arranged on the opposite side of the first portion with respect to the second portion. 
     Preferably, the slate retainer is formed, at least partially, from a sprung wire such as sprung steel wire. More preferably, the slate retainer is formed entirely from sprung wire. Here the fixing locations may be formed by a loop of wire. Furthermore, the second portion may be formed by bending the wire to create at least one elbow. A hook may be formed by creating at least two elbows. Furthermore, the locating portion may be formed by bending the wire. Moreover, the middle portion may be formed by creating a looped section of wire. The loop may be a full loop or a portion thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: 
         FIG. 1  shows a conventionally covered roof; 
         FIG. 2  illustrates using a ripper tool to remove a broken slate from a roof; 
         FIG. 3  shows a pictorial view of a first embodiment of a slate retainer; 
         FIG. 4  shows a pictorial view of a second embodiment of a slate retainer. 
         FIG. 5  shows a pictorial view of a third embodiment of a slate retainer. 
         FIG. 6 and 7  show plan and side elevation views of  FIG. 5 . 
         FIG. 8  shows a side elevation view of a fourth embodiment of a slate retainer. 
         FIG. 9  shows plan and side elevation views of a fifth embodiment of a slate retainer. 
         FIG. 10 and 11  show process steps detailing a method of replacing a broken slate using the slate retainer shown in  FIGS. 5 to 7 . 
         FIG. 12   a  and  12   b  show a perspective and side elevation view respectively of a tool for use in replacing a broken slate using the slate retainer. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE 
     Referring to  FIG. 1 , a conventional roof  10  is shown. The roof  10  has a plurality of batons  20  secured in parallel lines and at a predetermined spacing. The roof  10  is slated by securing a first, lowermost, row of slates  30   a  to the roof. Further slate rows  30   b  and  30   c  are added working up the roof. Each slate is pre-drilled with two fixing holes. Each slate is secured to the roof by locating an uppermost edge or head of the slate on a respective head baton  22   a  (i.e.  22   c  for slate  30   c ). The slates can then be nailed to a respective fixing section  24   c  using nails  40 . It will be appreciated that the respective head baton of a lower slate forms the respective fixing baton of the next upper level of slates. Furthermore, a lowermost edge of each slate extends so as to conceal the nail heads of the row of underlying slates. 
     Referring to  FIG. 2 , a ripper tool  50  is used to remove a broken slate and to pull the redundant nails  40  from the batons (i.e. in nails previously used to hold the broken slate in place). This can be done without affecting the surrounding slates. 
       FIG. 3  shows a first embodiment of a slate retainer  100 . The slate retainer  100  is a single piece. The slate retainer  100  includes a first portion  110  and a second portion  120 . The first portion  110  and the second portion  120  are joined by a middle portion  130 . Here, the first portion is shown as a fixing location  112 . The first portion is sized so as to be greater than the gap between the two underlying slates. Thus the first portion provides an anchor point located, in use, above the underlying slates. Suitably, the slate retainer is formed from a continuous piece of sprung wire. Thus, because the middle portion is formed from a straight piece of wire, the second portion can resiliently flex relative to the anchor portion as indicated by arrow A. Here, the second portion  120  comprises an upwardly bent portion of wire  122 . Consequently, from the description which follows, it will be appreciated that the second end, in use, can flex between two underlying slates. Consequently, as a replacement slate is slid into position, the second portion  120  is able to resiliently flex between the two underlying slates with a distal end  124  pushing upwardly against the replacement slate. When the replacement slate is slid upwardly so that the distal end is clear of the replacement slate, the resiliency of the middle portion causes the second portion to spring upwardly. Thus as the replacement slate is released and urged to slide downwardly under gravity, the replacement slate abuts the upwardly bent portion  122 . Thus the slate retainer holds the replacement slate in position. Advantageously, because only the upwardly bent portion  122  is visible, the slate retainer is very discrete. Moreover, because the slate retainer is one piece, it is easy to install. 
     Referring to  FIG. 4 , a slate retainer  200  according to a second embodiment is shown. The slate retainer  200  is a single piece having a first end  210 , a second end  220  and a middle portion  230 . However, the slate retainer  200  also includes a locating portion  240 . The locating portion  240  extends from the opposite side of the first portion to that of the second portion and comprises a downwardly bent portion of wire. Consequently, the locating portion extends in an opposite direction to the second portion (e.g. one extends in a positive z-direction and the other extends in a negative z-direction). In use, the locating portion  240  is able to locate permanently between the two underlying slates, even when the second portion  220  flexes. 
     Consequently, the locating portion  240  enables the slate retainer  200  to be quickly and correctly located. As will be herein described, the locating portion is aligned with fixing locations  212   a  and  212   b  and the second portion  220  along the same axis (axis y of  FIG. 4 ). 
     The first portion  210  of the slate retainer  200  is shown in  FIG. 4  as suitably including two fixing locations  212   a  and  212   b.  Each fixing location  212  is an aperture formed from a loop of the wire. The distance between the fixing location  212   a  and the second portion  220  is arranged to be suitable for a first standard baton spacing. Whereas, the distance between the fixing location  212   a  and the second section  220  is arranged to be suitable for a second standard baton spacing. Thus, the slate retainer  200  may be used on roofs having either the first or second standard spacing. Referring to  FIG. 4 , the fixing locations  212  lie in the x-y plane. 
     In contrast to the first embodiment, the middle portion  230  of the second embodiment is not only able to flex up and down in the z-direction (indicated by arrow A), but is also resiliently extendable in the y-direction. Suitably, the middle portion is formed from a partial loop of wire. For instance, as shown in  FIG. 4 , the middle portion forms a substantially semi-circular loop of wire. Consequently, the second portion extends on the same axis as the fixing locations. This is necessary in order for the fixing locations  212  and the second portion  220  to locate over the gap between the two underlying slates. Because the middle portion  230  is resilient, the second portion  220  can be moved in the y-direction to extend the distance between the fixing locations  212  and second portion  220 . It will be appreciated that this acts to flatten the loop of sprung wire. When the second portion is released, the resilient nature of the middle portion  230  causes the second portion  220  to return to its initial position relative to the fixing locations  212 . The middle portion  230  is shown as a loop of the sprung wire extending in the x-y plane. Suitably, the loop extends, relative to the length of the batons, a greater distance than the gap between the slates. That is the radius of the middle section may be greater than 10 times or greater than 20 times or greater than 30 times the gap between the underlying slates. Consequently, in this embodiment the middle portion  230  forms an anchor. This is because the middle portion, in use, is arranged on top of the underlying slates and the resilient nature of a bend  232  causes the second portion  220  to flex between the underlying slates. 
     The second portion  200  of the slate retainer  200  is shown in  FIG. 4  as a hook  226 . The hook  226  is shown as a portion of the sprung wire being bent 180° about a bend having a radius r. The radius r is suitably sized so as to be the same as a thickness of the replacement slate. In order to accommodate variances in slate thickness, the radius may be greater than the thickness of the slate. For instance, the radius may be greater than the slate thickness, by less than 50% or by less than 20% or by less than 10% of the slate thickness. Importantly, the hook  226  is sized so that it can flex completely between the two underlying slates. The hook  226  includes a length of wire  228  that runs back toward the fixing location. The length of the wire  228  is less than the distance that the middle section can resiliently expand in the y-direction. Alternatively the hook  216  may comprise an end portion of the sprung wire being bent to extend at right angles and the tip being bent over a further 45 degrees. Consequently, although the hook still springs around the foot of a replacement slate, the slate retainer has to expand a lesser degree. 
     In use, as the replacement slate is slid into position, the hook is able to flex downwardly between the underlying slates. When the slate is in position, the hook  226  remains in contact with the replacement slate as the hook does not move clear of the replacement slate. Thus, a tool can be used to cause the hook  226  to move in the y-direction due to the expansion of the middle portion. Once the hook  226  is clear of the relevant slate, the resilient nature of the middle portion  230  causes the hook  226  to flex upwardly, out of the gap between the two underlying slates and also contract to its original distance from the fixing locations  212 . Thus the hook is arranged about the replacement slate. 
     It may be desirable to cause the hook to hold the replacement slate in a tensioned state. In this case the distance between the second portion  220  and the fixing location  212 , in the unstressed state is arranged to be less than the desired distance between the respective fixing batons and foot of the replacement slate. Thus, when hooked on a replacement slate, the middle portion remains in an extended state along the y-direction and therefore applies a force on the replacement slate acting to urge the replacement slate upwardly. It will be appreciated that this upwardly force would be resisted either by the replacement slate abutting nails in higher rows or it would be insufficient to overcome the gravitational force of the replacement slate so that the replacement slate remains in the correct alignment on the roof. 
     Referring to  FIGS. 5-7 , a third embodiment of a slate retainer  300  is shown. The slate retainer  300  includes a first portion  310 , a second portion  320  and a middle portion  330  formed from a continuous, single piece of sprung wire. The first portion  310  and second portion  320  are substantially the same as the first  210  and second portions  220  of the second embodiment  200 . Moreover, the slate retainer  300  also includes a locating portion  340  substantially the same as the locating portion  240  of the second embodiment  200 . Whilst the middle portion  330  of the slate retainer  300  is able to resiliently expand in the y-direction and also enable the second portion  320  to resiliently flex between the underlying slates, the middle portion  330  is shown in  FIGS. 5-7  as comprising a substantially circular loop  334  and a straight extension  336 . The straight extension  336  extends under (with respect to the replacement slate) the loop  334 . This is advantageous because the substantially circular loop  334  provides the second portion  320  with greater resiliency in the y-expansion. Moreover, the straight extension  336  provides greater distance between resilient bend  332  and the hook  326 . Consequently, to obtain the same movement of the hook  326  between the underlying slates requires reduced twisting of the bend  332 , which further improves the resiliency. As shown in  FIGS. 5-7 , the loop  334  extends in the x-y plane, and the straight section is coincident with the hook  326  such that it is arranged, in use, directly above the gap between two underlying slates. 
       FIG. 8  shows a fourth embodiment of a slate retainer  400 . The slate retainer  400  includes a first portion  410 , a second portion  420  and a middle portion  430 . The slate retainer also includes a locating portion  440 . The slate retainer  400  is substantially the same as the slate retainer  300  of the third embodiment. However, the second and third portions are arranged in a plane angled to the x-y plane of the fixing locations. Consequently, when the slate retainer  400  is secured to a respective fixing baton, the middle portion rises upwardly rather than being parallel to the replacement slate. This provides improved resiliency. 
     Referring to  FIG. 9 , a fifth embodiment of a slate retainer  500  is shown. The slate retainer  500  comprises a first portion  510 , a second portion  520  and a middle portion  530 . A locating portion  540  is also included. The first and second portions are substantially as herein described. The locating portion  540  is substantially as herein described. However, rather than being a loop as described in relation to locating portion  340 , locating portion  540  is a straight piece of wire extending at right angles to the first portion. Whilst the middle portion  530  is able to resiliently expand in the y-direction and also enable the second portion  520  to flex between the underlying slates, the middle portion  530  is shown in  FIG. 9  as comprising a snaking length of a sprung wire. Suitably, the snaking length of sprung wire includes a first, second and third u-shaped bend  538 . Each u-shaped bend causes the sprung wire to turn back on itself through 180°. As with the second through fourth embodiments, the middle portion acts as an anchor and extends a greater extent relative to the length of said batons than the gap between the slates. The resiliency in the bends  538  causes the middle portion  530  to allow the second section  520  to move further away from the fixing locations but biases the second portion to return to the original position once a force is removed. Thus whereas in the second, third and fourth embodiments a single loop of sprung wire are provided. 
     A method of using the slate retainer  300  will now be described with reference to  FIGS. 10 and 11 . It will be appreciated however, that the method will be equally applicable to securing a replacement slate using any of the slate retainers described above. 
     As shown in  FIG. 10 , a broken slate is first removed from the roof. This includes removing the nail fixings previously used to hold the broken slate in place. A ripper tool may be used as in known replacement methods. A slate retainer  300  is then secured to a respective fixing baton of a course of underlying slates. The respective fixing baton is visible through a gap and found between two underlying slates. The slate retainer  300  is secured by driving a nail or other fixing through the fixing location  212 . Once secured, the hook  326  is arranged slightly above the desired level of the foot of the replacement slate. The middle portion  330 , forming the anchor, is arranged on top of the two underlying slates and the second portion  320  arranged spaced above the gap between the two underlying slates. The locating portion  340  locates easily and quickly between the two underlying slates in order to aid assembly to the roof. 
     As shown in  FIG. 11 , a replacement slate  30   r  is slid upwardly with respect to the roof to locate in the space of the removed slate. In sliding the replacement slate upwardly, the replacement slate abuts the hook causing the hook to flex downwards between the slates. Consequently, the hook does not interfere with the replacement slate and as such, the replacement slate can be located correctly on its respective head baton. Once the replacement slate  30   r  is in position a tool, such as a ripper tool  50  can be used to pull the hook  326  downwardly. Here the ripper  50  is slid under the replacement slate and then a barbed portion used to catch the hook  326 . By pulling the hook  326  downwards, it is able to move clear of the replacement slate. When it is clear, the natural resiliency provided by the middle section causes the hook to flex upwards and contract thereby securing the replacement slate in position. 
     As an alternative to causing the hook  326  to move downwardly, clear of the replacement slate using the ripper, a tool may be used. A suitable tool  600  is shown in  FIG. 12 . The tool  600  includes a catch  610  a handle  620  and an elongate middle section  630 . The catch is sized so as to fit about the hook  326  of the slate retainer. Suitably, the catch is shown in  FIG. 12  as an eyelet. The handle  620  is sized so as to be gripped by the fingers of a user. Suitably, the handle is shown in  FIG. 12  as a substantially circular loop of wire. The handle  620  is bent upwardly with respect to the elongate middle section to aid gripping. Suitably, the handle is shown being bent at an angle A of approximately 45°. The elongate middle section is substantially straight. Suitably, the elongate middle section is substantially straight. Suitably, the elongate middle section is formed from a length of wire. Advantageously, the tool may therefore be formed from a single, continuous length of wire. As shown in  FIG. 12 , although not essential, the elongate middle section may include a kink  632 . The kink  632  extends downwardly. In use, once a slate retainer has been secured to the roof but before a replacement slate is arranged is position, a tool  600  is hung from the hook. This is done by causing the catch  610  of the tool  600  to locate about the hook. The kink  632  locates in the gap between the two underlying slates in order to give the tool some positional stability. The elongate middle section  630  is long enough so that the handle is located so as not to interfere with the locating of the replacement slate. Once the replacement slate is arranged in position, the handle can be pulled downwardly in order to extend the slate retainer so that the hook moves clear of the replacement slate and is therefore able to spring upwardly to hook the replacement slate. 
     Advantageously, the slate retainer and method herein described allows replacement slates to be quickly and easily installed. Moreover, the slate retainers provide improved aesthetics as only a minimal portion of the hook is visible. Furthermore, the slate retainers provide improved securing as the replacement slates are less likely to be dislodged.