It is known to provide an overhanging portion at the top of the security fence or wall, as a deterrent to scaling of a fence or wall. Hitherto, the overhanging portions have been formed by strands of wire such as barbed wire or razor wire or by welded wire meshes, which are supported between brackets secured to the top of the fence or wall. Both these options have the drawback that the wire strands or wire meshes provide a grip for scaling the fence or wall or means for engagement of a grappling hook.

In accordance with one aspect of the present invention, a security fence or wall comprises a plurality of brackets secured to the top of the fence or wall at spaced intervals along the length of the fence or wall, each bracket has an upright portion, the lower end of which is secured to the fence or wall, a curved portion extends from the upper end of the upright portion to the side of the fence or wall which is open to attack, the curved portions extending upwardly from the upright portion, the end of the curved portion remote from the upright portion extending downwardly ; characterised in that an expanded metal mesh is secured between the brackets to provide a curved overhang which extends along the top of the fence or wall on the side of the fence or wall open to attack, the expanded metal mesh defining sets of closely spaced louvers running parallel to the top of the fence or wall, the louvers on the portions of the mesh secured to the upright portions of the brackets sloping downwardly towards the side open to attack.

With the security topping disclosed above, the louvers of the expanded metal mesh are spaced sufficiently closely, so that a person trying to scale a fence or wall cannot get their fingers between adjacent louvers.

Moreover, as the louvers slope downwardly towards the side open to attack, they do not provide a grip for scaling the wall or for engagement by a grappling hook.

According to a preferred embodiment of the invention, the vertical separation between the louvers is less then 15mm. More preferably, the vertical separation is from 5 to 10mm. The louvers are preferably angled at from 45° to 20° to the plane of the mesh.

The curved portions of the brackets are preferably arcuate and extend from 130° to 180°. The brackets are preferably made of spring steel so that the overhang will collapse if an attempt is made to scale the inside of the outer portion of the overhang.

A reinforcing layer of mesh may be secured inside the apex of the curved overhang, as an obstacle to the cutting of this portion of the overhang.

The invention is now described by way of example only, with reference to the accompanying drawings, in which:- Figure 1 shows a perspective view of a wall with security topping in accordance with the present invention; Figure 2 shows a section through the security topping of Fig. 1; Figure 3 is a front view of the mesh used in the security topping of the fence shown in Fig. 1;

Figure 4 is a section along the line IV-IV of Fig. 3; and Figure 5 is a view similar to Fig. 2, showing a modification to the fence illustrated in Fig. 1.

As illustrated in the accompanying drawings, a security wall 10 has a plurality of brackets 12 secured to the top of the wall 10, at spaced intervals along its length. The brackets 12 are of inverted'J' configuration having an upright portion 14, which is secured to the wall by suitable, non-releasable fastening means, for example security bolts.

The upper portion 16 of the brackets 12 is of arcuate configuration extending from 130° to 180°, for example 150°. The upper portion 16 of the brackets are disposed substantially at right angles to the wall 10, extending to the side of the wall 10 that is open to attack.

The brackets 12 are made of spring steel so that they will collapse under the weight of an assailant attempting to scale the wall 10.

An expanded wire mesh 20 is secured between the brackets 12 along the length of the wall 10, so as to form an arcuate overhang 22 which extends the length of the wall 10 on the side thereof which is open to attack. The expanded metal mesh 20 is secured to the brackets by a suitable non-releasable fastening means, for example riveting or welding.

The mesh 20 may furthermore be secured on the inside of the overhang 22, to the top of the wall 10, in suitable manner.

As illustrated in greater detail in Figs. 3 and 4, the expanded metal mesh comprises series of parallel louvers 24 interconnected by web portions 26, the louvers 24 running parallel to the top of the wall 10. In a suitable configuration, the louvers 24 are angled at about 40° to the plane of the mesh 20, have a spacing of the order of 7 to 7.5mm and are of the order

of 70 mm long. The mesh 20 is formed from metal sheet of about 3 mm thickness and the louvers 24 are of the order of 6 mm wide. The mesh is made of metal of sufficient strength to resist manual deformation of the louvers 24.

The expanded metal mesh 20 is secured to the brackets 12, so that in the portion 30 secured to the upright portions 14 of the brackets 12, the louvers 24 will be angled downwardly towards the side of the wall 10, that is open to attack. In this manner, the louvers 24 will not provide a grip for scaling of the portion 30 of the mesh 20.

As the mesh 20 goes over the arcuate portion 16 of the brackets 12, the portion 32 on the outside downwardly sloping part of the overhang 22 will again have the louvers 24 angled downwardly to the outside of the overhang 22, again not providing a grip for the scaling of the outside of the overhang 22.

While the louvers 24 will provide a grip on the inside of the outer portion 32 of overhang 22, if an assailant attempts to scale the overhang 22 from inside, the spring steel brackets 12 will collapse, springing back into place when the assailant's weight is removed.

Furthermore, the louvers 24 will be angled upwardly on the side opposite to the side open to attack, on the portion 34 thereof, extending upwardly from the wall 10 and will not consequently provide formations which may be engaged by a grappling hook which is thrown over the overhang 22, from the side of the wall 10 open to attack.

As illustrated in Fig. 5, an additional strip 30 of expanded metal mesh 20 may be secured along the apex of the overhang 20 on the inside thereof.

This additional strip 34 of mesh 20 will provide reinforcement in this area

and act as a deterrent to cutting of the mesh 20. The orientation of the mesh 20 and strip 30 may be reversed with respect to that forming the overhang 22, so that the louvers 24 are angled in opposite directions.

Various modifications may be made without departing from the invention.

For example while in the above embodiment the security topping is mounted on top of a wall, a similar arrangement may be used on top of a security fence. When formed on a security fence, the brackets may be secured to the upper parts of the fence supports. The mesh forming the overhang may be a continuation of the mesh used for the fence itself.