GB2196363A

GB2196363A - Brick wall coping system

Info

Publication number: GB2196363A
Application number: GB08724415A
Authority: GB
Inventors: Colin James Michael Knox; Robin Hood-Leeder
Original assignee: Redland Bricks Ltd
Current assignee: Redland Bricks Ltd
Priority date: 1986-10-20
Filing date: 1987-10-19
Publication date: 1988-04-27
Anticipated expiration: 2007-10-19
Also published as: GB8724415D0; GB2196363B; GB8625098D0

Abstract

A brick wall coping system which is suitable for a cavity wall comprises a first and second top layer of bricks 12 and 14 which define a cavity 15 between them, and a layer of capping units 16, which straddle the top layers of bricks. The second top layer 14 is usually a course of bricks higher than the first top layer 12, with an under surface 19 of the capping units 16 resting on and receiving the second top layer 14. An overhang 20 is provided on the capping units 16 which extends beyond the second top layer 14. Often the second top layer bricks 14 have special profiles which match the profile of the under surface of the capping unit 16. A damp proof course layer is provided in the mortar 17 and this is sandwiched between the capping unit 16 and the top course layers 12 and 14. <IMAGE>

Description

SPECIFICATION Brick wall coping system The present invention relates to a coping system for a brick wall, in particular a cavity wall.

It is standard practice in the case of cavity walls which form a parapet to provide a coping system including a damp proof course (DPC) in order to minimise the downward seepage of moisture, which tends to cause degradation.

Existing coping systems suffer various disadvantages. Those which use simple brick profiles tend to have a line of weakness at the DPC with the result that the overlying layers are susceptible to being dislodged.

Those systems which address themselves to this danger tend to use a number of nonstandard and often complicated brick profiles.

This increases the cost considerably but does not appear satisfactorily to have solved the problem at the line of weakness.

It is an object of the present invention to provide a coping system for a brick wall which minimises downward ingress of moisture and in which the top brick layers are firmly located.

It is a further object of the invention to provide a coping system which is less costly and easier to build than the known arrangement.

According to the present invention, there is provided a coping system for a brick wall comprising a first top layer of bricks, a second top layer of bricks spaced from the first top layer to define a cavity therebetween, and a layer of capping units which straddle the first and second top layers and the cavity; the second top layer being at a higher level than the first top layer, and the capping units each having an under-surface comprising a land at one end arranged to rest on the first top layer, an overhang at the end opposite the said one end and a recess formed between the land and overhang, the recess being arranged to receive the second top layer whereby the overhang extends beyond the second top layer.

The capping unit is fixed to the two top layers preferably by means of mortar joints.

Preferably, the DPC is located in the mortar joints between the capping unit and the two top layers, and to a large extent may therefore follow the contour of the underside of the capping unit.

Thus, the capping unit effectively "grips" the second top layer making it highly resistant to being dislodged.

Preferably, the second top layer is higher than the first top layer by a distance equal to the height of one course of bricks. The first and second top layers may be composed of standard bricks, though bricks having special profiles may be used, particularly in the second top layer.

For example, special profile bricks may have curved or rounded edges, and for sloping or curved sides, and for channels running parallel to and along the sides. Advantageously the recess of the capping unit substantially matches the profile of the top and sides of the special profile brick with which it is to be used. The edges of the capping unit may also be rounded. The special profile bricks may be wider than the supporting standard bricks.

Preferably the capping unit has a front face which is flush with the first top layer. This would normally constitute the front of the wall, while the capping unit overhang would be at the rear of the wall.

Another preference is that the top surface of the capping unit slopes downwardly towards the overhang. Suitably the capping unit has a chamfered edge between the front face and the top surface. The chamfered edge may be concave.

An advantage of the system of the inven tion arises when there is a roof e.g. a flat roof at the rear of the wall. In previous arrangements, it is normal to extend the roof lining, which may be of bitumen or roofing felt for example, up the rear of the wall to an extent and then to render the roof/wall junction waterproof by employing lead flashing.

This is embedded in a mortar joint between two courses of bricks above the lining and is then folded down to overlap the top of the lining.

In the system of the invention, the flashing can be left out altogether. The DPC can be extended out from beneath the overhang and brought down over the top of the roof lining.

This represents a significant economy, since the flashing tends to be very costly.

The invention may be carried into practice in various ways and some embodiments will now be described by way of example with reference to the accompanying drawings, in which: FIGURE 1 is an isometric sketch of a coping system in accordance with the invention; FIGURE 2 is a side elevation of the coping system shown in FIGURE 1; and FIGURES 3 to 7 are side elevations of five alternative embodiments.

Referring firstly to FIGURES 1 and 2, a coping system is shown for a cavity wall. The wall comprises an outer leaf 11 having a top course of standard bricks 12 and an inner leaf 13 having a top course of standard bricks 14.

The two leaves 11, 13 define between them a cavity 15. A series of capping units 16 are located on top of the two top courses 12, 14. The various components are joined together by mortar joints 17.

The inner leaf top course 14 is one course higher than the outer leaf top course 12. Each capping unit 16 has an underside which includes a land 18 which sits upon the outer leaf top course 12. The underside'also has a recess 19 which accommodates the inner leaf top course 14. Beyond the recess 19 there is an overhang 20 which extends to a level below the top surface of the inner leaf top course 14 and serves to protect the joint between the capping unit 16 and the inner leaf 11. Thus, the inner leaf top course 14 is effectively gripped by the capping units 16.

Each capping unit 16 has a vertical front face 21 which is flush with the outer leaf 11 and a chamferred region 22 which leads to a gently backwards sloping top surface 23. A damp proof course 24 is located beneath the capping units 16 and is held in place by the mortar joints between the capping units 16 and the two top courses 12,14.

The embodiment shown in FIGURE 3 differs from that of Figures 1 and 2 in that the recess 39 of the capping unit 36 has a rounded profile.

The embodiment shown in FIGURE 4 is similar to that shown in FIGURE 3 but the capping unit 46 has a concave chamfer 47. In addition, the bricks forming the inner leaf top course 44 each have a curved top surface which matches the profile of the recess 49.

In the embodiment shown in FIGURE 5, the inner leaf top course 54 differs in that the units are wider and have a deep chamfer 57 facing towards the outside of the wall. The capping units 56 have a correspondingly shaped recess 59 which has a short vertical portion 53 and an angled portion 55 which follows the chamfer 57. This arrangement allows for a more-or-less continuous mortar joint along the underside of the capping unit 56.

The embodiment shown in FIGURE 6 is similar to that shown in FIGURE 5 except that the inner leaf top course units 64 have a curved profile 67 replacing the deep chamfer 57 in the previous embodiment. The recess 69 is curved at 65 to match the curved profile 67.

In a further embodiment shown in FIGURE 7 the inner leaf top course 74 differs in that the units are wider than standard bricks and have sides that slope inwardly to the top of the top course 74. The capping unit 76 has a correspondingly shaped recess 79 and an overhang 20 that extends downwards to the same level as the bottom of the top course 74. The edge of the overhang 20 which faces the recess 79 is formed with a chamfer 71.

Each unit forming the inner leaf top course 74 has two semicircular channels 75 that run parallel to and along each side of the units.

Naturally, any number of channels 75 may be provided.

It is to be understood that the various features of the profiles of the inner leaf top course and the capping units as described in the various embodiments may be combined to give further embodiments of the invention.

It will be appreciated that in all the embodiments described, a damp proof course would be provided, in an equivalent position to that shown in FIGURE 2. Furthermore, the concave chamfer 47 shown in FIGURE 4 could be incorporated in any of the other embodiments.

Claims

1. A coping system for a brick wall comprising a first top layer of bricks, a second top layer of bricks spaced from the first top layer to define a cavity therebetween, and a layer of capping units which straddle the first and second top layers and the cavity; the second top layer being at a higher level than the first top layer, and the capping units each having an under-surface comprising a land at dne end arranged to rest on the first top layer, an overhang at the end opposite to the land and a recess formed between the land and the overhang, the recess being arranged to receive the second top layer whereby the overhang extends beyond the second top layer.

2. A system as claimed in Claim 1 in which the capping unit is fixed to the two top layers by mortar joints.

3. A system as claimed in Claim 2 in which a damp proof course is located in the mortar joints between the capping unit and the two top layers.

4. A system as claimed in any of Claims 1, 2 or 3 in which the second top layer is higher than the first top layer by a distance equal to the height of one course of bricks.

5. A system as claimed in any of Claims 1 to 4 in which the first and second top layers of bricks are composed of standard bricks.

6. A system as claimed in any of Claims 1 to 4 in which the units of the second top layer of bricks have rounded edges and/or sloping or curved sides.

7. A system as claimed in Claim 6 in which the units of the second top layer of bricks are provided with semi-circular channels running along and parallel to the sides of the units.

8. A system as claimed in Claim 6 or 7 in which the units of the second top layer are wider than standard bricks.

9. A system as claimed in Claims 6 to 8 in which the recess of each capping unit substantially matches the profile of the second top layer of bricks.

10. A system as claimed in any of Claims 1 to 9 in which the capping unit has a front face which is flush with the first top layer.

11. A system as claimed in any of claims 1 to 10 in which a top surface of the capping units slopes downwardly to the overhang.

12. A system as claimed in Claim 10 or Claim 11 in which the capping units are provided with a chamfered edge in between the front face and the top surface.

13. A coping system for a brick wall constructed and arranged substantially as herein specifically described with reference to and as shown in any one of the accompanying drawings.