IE42561B1 - Lintels - Google Patents

Description

The invention relates to lintels, and concerns metal lintels, particularly though not exclusively for use in cavity walls.

According to the invention there is provided a lintel for spanning an aperture in a wall, having a boundary surface comprising a metal plate and which in use is a rear surface of the lintel and, extending over substantially the whole rear surface of that metal plate, an insulating material.

Two lintels embodying the invention are hereinafter described, by way of example, with reference to the accompanying drawings, in which:Figure 1 shows a side elevational view of one lintel; and 10 Figure 2 shows a side elevational view of a second lintel.

Referring to the drawings in which like parts are indicated by like numerals, Figure 1 shows a metal lintel 1 for spanning an aperture in a cavity wall. The lintel 1 has an upper substantially horizontal plate, part or member 2 for supporting an inner skin of the wall above the aperture and a lower substantially horizontal plate part or member 3 for supporting an outer skin of the cavity wall.

A support plate, part or member 4 connects the plates 2 and 3.

When the lintel is in position in a cavity wall, the plate 4 extends across the cavity. A vertical plate or member 5 extends downwardly from the first plate 2 - 2 at or adjacent a rear edge thereof and connects with a substantially horizontal (in use) plate, part or member 6 which in use extends across the cavity and connects the front and rear surfaces of the lintel 1 as defined by the plates 3 and 4, and 5 respectively.

The lintel thus has a hollow box-like configuration the box being defined by the plates 2, 4, 6 and 5.

The plate 6 between the front and rear surfaces of the lintel has means for preventing or hindering heat transfer in the form of a plurality of holes or perforations 7 through it, as shown in Figure 2. The holes 7 decrease the amount of metal in the plate 6 and thus decrease the heat transfer gradient between the front and rear boundary surfaces (i.e. those parts to the left and right respectively as viewed in Figure 1) of the lintel so that in use the inner skin of the wall is not subjected to a cooling effect owing to the heat transfer property of the metal between the inner and outer surfaces of the lintel.

The holes 7 are generally rectangular with rounded corners.

The holes 7 form a series of straight parallel rows each extending longitudinally of the lintel, the holes in one row overlapping the holes in an adjacent row, so as to lengthen the path between the front and rear boundary surfaces of the lintel. The holes could be oblong as shown at 8, Figure 2, one inch long by a quarter of an inch and with a lengthwise spacing of half an inch. In this case the plate is 8.5 inches wide, the perforations occupying a five inch span which commences at a distance of 3/4 of an inch from one (in use, rear) edge of the plate 6.

The holes 7 could, it will be understood, be of any desired configuration, for example of cruciform shape.

The lintel also has a metal mesh or lathing for facilitating the adhesion of plaster, etc. Between the mesh 10 and the vertical support plate 5 there is means for preventing or hindering heat transfer in the form of a layer of insulating material 11 such as “wood wool i.e. an insulating material formed from wood shavings bonded with a cement slurry. - 3 42561 The wood wool can be forced between the mesh and support using a ram.

Tt could, however, be applied using an adhesive, and/or clamps.

Figure 2 shows a lintel 20 in which the rear plate 5 has downwardly and upwardly directed upper and lower lips or flanges 12 and 13. A block of wood wool 14 having end grooves 15 can then be mounted in position by lining up the grooves and flanges and sliding it into the lintel 20. The wood wool block 14 then projects laterally beyond the rear face of the lintel and plaster etc. can be applied directly thereto. Also, the block 14 does not extend over the full height of the lintel so that recesses 16 and 17 are formed which provide keying means for plaster, mortar or cement.

The lips or flanges could be-formed on the plates 2 and 6. The plate 6 has perforations 7, 8.

Alternative materials such as polyurethane or other foam could also be used in place of wood wool 11, 14. These foams could be injected using a foam gun.

It will be understood that the holes 7 can also provide keying means for mortar, plaster, cement and the like.

It will also be understood that the holes extend over substantially the 2o whole surface area of a plate 6 of a particular lintel.

It will also be understood that the lintels shown and described are by way of example only and that various modifications may be made. For example, the plate 4 may be of any desired shape providing it joins the plates 2 and 3 and in use extends across the cavity of a cavity wall to act as a deflector plate for moisture may condense in the cavity.

The metal lintels may be made of galvanised sheet steel plates. Or they may be made from metal coated with plastics. The holes in the different rows may not be staggered.

Claims (5)

1. A lintel for spanning an aperture in a wall, having a boundary surface comprising a metal plate and which in use is a rear surface of the lintel and, extending over substantially the whole rear surface area 5 of that metal plate, an insulating material.

2. A lintel according to Claim 1, in which the insulating material comprises a wood wool thermal insulating material.

3. A lintel according to Claim 2, in which the insulating material is a block of material and in which the block and the lintel have 10 complementary means for securing the block and lintel together.

4. A lintel according to Claim 3, in which the means of the block comprises a groove and the means for the lintel comprises a lip.

5. A lintel for spanning an aperture in a wall, substantially as hereinbefore described with reference to and as shown in the accompanying 15 drawings.