GB2479219A

GB2479219A - Joist assembly

Info

Publication number: GB2479219A
Application number: GB1013134A
Authority: GB
Inventors: Douglas William Cullen; Andrew Rollo
Original assignee: Intelligent Wood Systems Ltd
Current assignee: Intelligent Wood Systems Ltd
Priority date: 2010-02-26
Filing date: 2010-08-04
Publication date: 2011-10-05
Anticipated expiration: 2030-08-04
Also published as: GB2479219B; GB201013134D0; GB201003303D0

Abstract

The assembly comprises a support member 12 and a solid timber joist 14, the support member includes a channel 18 that has a base 24, and the joist includes an elongate member 30 which defines a first surface 32, the joist and support member arranged so that the base and first surface abut with each other in use. A notch 36 is defined on the joist between the first surface and a second surface 34, a reinforcing member 16 is located at the notch. Also claimed is a reinforcing member comprising a base plate, first and second plates extending therefrom and a connecting means for connecting the member to a joist. The first and second plates may have lips which extend to the underside of a joist. The reinforcing member may be metal and fixed to a joist by using a screw or a number of stabs formed on the reinforcing member.

Description

IL

SOLID TIMBER JOIST ASSEMBLY

The present invention relates to timber building construction and in particular, though not exclusively, to a solid timber joist assembly for hanging a solid timber joist in construction.

In building construction sets of, parallel arranged, supporting walls or beams are typically erected. Joists are then located at intervals, spanning the supports, to provide the necessary structure for laying floors or ceilings. While timber frame construction is widely used, the typical joists are not formed of a solid timber section. Engineered joists are formed as I beams or open web beams.

In each case two strips or chords of wood are arranged to provide upper and lower surfaces, the strips are then joined via either; a slim vertically arranged panel, forming the characteristic cross-sectional I'; or, open webs of metal strips which form a zig-zag arrangement on the sides of the strips.

I-beams and open webs have advantages in construction, for example, I-beams are lightweight and cost effective, whilst open webs allow easy access for services through the joist and by using an extended top chord, they can be top mounted (Top hung) onto most structural supporting members, removing the need to use fasteners or other building components. However, solid timber joists show increased strength, stiffness and acoustic properties over I-beams and open web beams. There is thus a need to provide joists which can combine the advantages.

It is therefore an object of the present invention to enable a solid timber joist to be top mounted onto structural supporting members without drastically reducing its performance.

According to a first aspect of the present invention there is provided a solid timber joist assembly comprising a first supporting member, the first supporting member including a channel located therein with a base of the channel defining a first abutting surface; a solid timber joist, the joist having a portion of an end removed to provide an elongate element protruding there from, the element including a second abutting surface created by removal of the portion and a notch created where the second abutting surface meets the joist; and a reinforcing member located in relation to the notch such that when the element is located in the channel, the abutting surfaces meet, a load is applied across the elongate element and the reinforcing member prevents failure of the joist Jocal to the notch.

In this way a lap joint is created between the supporting member and the joist, so that the joist supports itself. However, a failure mode is known to exist in timber where a notch has been removed and loading is applied. By using a reinforcing member to bridge the fault lines, failure is prevented as the reinforcing member transfers the structural load and thus the solid timber joist can support itself. Thus the advantages of a top hang arrangement are combined with those of a solid timber joist.

Preferably, the channel is of square profile so that it is easily machined and makes a close fit with the elongate element. The close fit ensures that a complete plane is presented for the floor to be laid upon. Preferably also, a depth of the channel is approximately equal to a width of the element. This arrangement provides the square profile.

Preferably, the reinforcing member comprises a plate including fixing means to attach the plate to a surface of the joist local to the notch. Alternatively, the reinforcing member may be a screw located through the joist from an upper surface to pass adjacent to the notch. In this way the reinforcing means can be pre-fitted to the joist before being brought to the construction site.

The plate may be substantially rectangular. Preferably also the plate may include an elongate section sized to locate upon the elongate element with the remaining section of the plate locating on a surface of the joist adjacent the notch. By creating a section of plate which allows the notch to be substantially surrounded on a face of the joist, the plate bridges the typical fracture lines.

There may be a pair of plates located on each side of the joist.

This provides symmetrical load bearing assistance.

Each plate may include a lip arranged to extend perpendicularly from an edge there upon. The lip may be arranged to locate upon the second abutting surface. Advantageously the lip extends along the length of the elongate element. In this way, additional reinforcing support is provided at the notch and the plate is more easily positioned with respect to the joist. A lip may also be arranged to extend over the upper surface of the joist. This provides strengthening vertically across the elongate member and assists in preventing bending of the joist at the notch.

Advantageously, the reinforcing member comprises a single piece plate having a mid-section to locate upon the upper surface of the joist and two opposing end sections which form plates on each side of the joist. This provides a single part member which can be positioned and attached to the joist easily.

The reinforcing member is preferably constructed from thin gauge steel. In this way, the member can be mass produced from sheets with members nested.

The fixing means may comprise a nail located through an aperture in the plate. Preferably, a plurality of apertures are located through the plate. Advantageously, the fixing means is integral to the plate. In this way the plate may be attached without requiring additional screws or nails. Preferably the fixing means comprise a plurality of stabs, wherein each stab is a prong, cut and bent from the plate. Both apertures and stabs may be present on the reinforcing member.

Preferably, the stabs are arranged to lie perpendicular to the plate. Alternatively, the stabs may be angled from the plate. The angle may be about 75 degrees.

According to a second aspect of the present invention there is provided a joist for use in timber frame building construction, the joist comprising an elongate rectangular member of substantially rectangular cross-section, wherein at a first end there is removed at least one portion of the member to provide an elongate element protruding therefrom and at least one reinforcing member is arranged on the joist local to the at least one removed portion.

Removal of a portion of the joist reduces the strength and stiffness of the joist at that position on the joist. By locating a reinforcing member at the vicinity of the removed portion, typical fault lines on the joist can be bridged and thus the joist has comparable strength and stiffness qualities of the same joist before the portion is removed.

Preferably the joist is a solid timber joist. In this way removal of a rectangular portion of the joist provides a notch, where the reinforcing member can be located in relation to.

Preferably a width of the elongate element is less than half a width of the joist. The width is typically taken from an upper surface of the joist to a lower surface, over the longest cross-sectional length. In this way, a substantial portion of the joist is removed at the end. The reduced width of the elongate element assists in designing the location of the joist in a structure.

There may be a pair of plates located on each side of the joist.

This provides symmetrical load bearing assistance.

According to a third aspect of the present invention there is provided a reinforcing member for use with a joist in a timber joist assembly, the member comprising a base plate having first and second plates extending therefrom and means for connecting the member to a timber joist.

In this way, the member can locate over a joist, with the first and second plates positioned over the potential fracture lines.

Preferably, the member is constructed of a thin gauge metal which can be pressed and folded. More preferably, the member is of single piece construction having two fold lines to create the first and second plates. Advantageously the fold is made so that the first and second plates are splayed. This allows the member to be more easily located upon a joist for fitting.

Preferably, the base plate is substantially rectangular and sized to locate across a typical solid timber joist on it's smaller dimension. Advantageously, the base plate may include apertures to facilitate the fixing of the member to a joist by locating nails or other suitable fixings there through.

Preferably, the first and second plates are mirror images of each other. Preferably also, the first and second plates are larger than the base plate. In one embodiment the first and second plates are rhomboid in shape. In a further embodiment the first and second plates are substantially rectangular. Preferably also the plates may include an elongate section protruding from a side of the rectangular section.

Each plate may include a lip arranged to extend perpendicularly from an edge there upon. Preferably, the lip extends from the elongate section. Thus the member can provide a portion which locates on three sides of a joist.

Preferably, the first and second plates include fixing means. The fixing means may comprise a nail located through an aperture in the plate. Preferably, a plurality of apertures is located through the plate. Advantageously, the fixing means is integral to the plate.

In this way the plate may be attached without requiring additional screws or nails. Preferably the fixing means comprise a plurality of stabs, wherein each stab is a prong, cut and bent from the plate.

Both apertures and stabs may be present on the reinforcing member.

Preferably, the stabs are arranged to lie perpendicular to the plate. Alternatively, the stabs may be angled from the plate. The angle may be about 75 degrees. Advantageously, the stabs are arranged such that when a splayed member is located over a joist, stabs positioned closest to the base plate will face the joist substantially perpendicularly. The length of the stabs may also vary across the first and/or second plate, being smaller in length towards the base plate.

Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings, of which: Figure 1 is an exploded view of an illustration of a solid timber joist assembly according to an embodiment of the present invention; Figure 2 is an illustration of the solid joist assembly of Figure 1, when assembled; Figures 3(a)-(e) are illustrations of a reinforcing member, according to a first embodiment of the present invention; Figures 4(a)-(d) are illustrations of a reinforcing member, according to a second embodiment of the present invention; Figures 5(a)-(e) are illustrations of a reinforcing member, according to a third embodiment of the present invention; Figures 6 (a) and (b) are illustrations of a reinforcing member, according to a fourth embodiment of the present invention; Figures 7 (a) and (b) is an illustration of a joist according to an embodiment of the present invention; Figure 8 is an exploded view of an illustration of a solid timber joist according to a further embodiment of the present invention; and Figures 9 (a) to (c) are illustrations of solid timber joist assemblies for different construction arrangements.

Referring initially to Figure 1, there is illustrated a solid timber joist assembly, generally indicated by reference numeral 10, according to an embodiment of the present invention. Assembly 10 provides a supporting wall 12, a solid timber joist 14 and a reinforcing member 16.

The supporting wall 12 may be a beam, block or metal construction, designed to support the weight of the solid timber joist 14. In the illustration, wall 12 is a solid timber joist of typical dimensions, say 210mm tall and 45mm wide. A channel 18 is removed from an upper surface 20 of the wall 12. The channel 18 is of rectangular cross-section having two side walls 22a,b with a width equal to the width of the wall 12 and a height larger than it's width. The height is selected to provide a sufficient bed to support an elongate portion of a further joist 14. The height may be up to one third of the height of the wall e.g. 70mm in this example.

The channel 18 has a base 24, providing a weight bearing surface 26.

Surface 26 is of square cross-section and has a width equal to the width of the wall 12.

A solid timber joist 14 is arranged perpendicularly to the wall 12.

The joist 14 has typical dimensions equal to those of the wall 12.

At a first end 28, a portion of the timber is removed to provide an elongate element 30. Element 30 has dimensions substantially equal to those of the channel 18. The removal of a portion leaves two surfaces 32,34 at the first end 28 of the joist 14. A surface 32 lies on the base of the elongate element 30 and has dimensions substantially equal to the base 24 of the channel 18. A second surface 34 faces the end of the joist 14. Where the surfaces 32,34 meet there is provided a notch 36. The notch 36 is effectively a right angled cut into the joist 14.

Located over the joist 14 is a reinforcing member 16. Reinforcing member 16 will be described in greater detail herein after with reference to the accompanying drawings. Member 16 is a strip of thin gauge steel or aluminium. Member 16 is arranged on the upper surface 38 of the joist 14, and folded such that a base or centre section 40 lies on the upper surface 38, and legs' in the form of extensions 42a,b, lie upon the side walls 44a,b of the joist 14. The centre section 40 spans the width of the joist 14 in one direction and has a sufficient length to span the notch 36 in the other direction. The section 40, however does not extend to the forward surface 46 of the elongate element 30 at the first end 28. Each leg 42 extends for a majority of the side wall 44, so that it spans the notch 36 in the vertical. The reinforcing member 16, thus surrounds the notch 36.

Reference is now made to Figure 2 of the drawings which illustrates the solid timber joist assembly of Figure 1 in an assembled configuration. Elongate element 30 is now located in channel 18.

This is a snug fit with surface 32 abutting and bearing down on surface 26. Upper surface 38 of joist 14 lies on substantially the same plane as upper surface 20 of the wall 12. This provides a working surface on which a floor or other boards can be laid.

It is noted that notch 36 lies against a corner 48 created between the base 24 of the channel 18 and the side wall 50 of the wall 12. A load is applied between the surfaces 32,26 with the result that an upward force acts on the elongate element 30. In a typical arrangement, as shown in Figure 2, two solid joist assemblies lOa,b are provided from a single solid timber joist 14 located between two parallel arranged supporting walls l2a,b. Each wall l2a,b has a channel 18a,b located therein and the channels are arranged to be collinear across the walls 12a,b. During construction, joist 14 is lowered from above to locate within the channels 18a,b. This is a simple construction method without a high degree of skill required.

In solid timber, the notch 36 will act as a point of weakness, and, due primarily to the grains in the timber, the timber will wish to fracture or split along the grain if a load is applied unevenly across the timber. Additionally, fault lines are created between the notch 36 and the upper surface 38 of the joist 14. These fault lines represent the shortest distance through the timber from the leverage point i.e. notch 36. The problem is exacerbated when the width of the elongate element 30 is less than half the width of the joist 14.

Thus while the problem is most alleviated when the width of the elongate section is half the width of the joist, the increased work in creating a deeper channel and in not being able to create channels of a standard depth, means it is more beneficial to have a smaller, standard, width of elongate element.

It is therefore the reinforcing member 16 which prevents the joist 14 from splitting at the notch 36 along one or more of the fault lines. The reinforcing member 16 is arranged to bridge the typical fracture lines and thereby provide reinforcement across the fault lines. Use of a reinforcing member 16 primarily replaces the strength lost in the joist when the portion is removed and the notch created. Ideally, the reinforcing member equalises the strength between a solid timber joist of typical dimensions and the same joist with a portion removed.

Reference is now made to Figures 3(a)-(e) which illustrate a reinforcing member 16, according to an embodiment of the present invention. As shown in Figure 3(a), the member 16 comprises a strip of thin gauge metal, probably steel or aluminium. The material is chosen to be easily cut and folded with a thickness which will not affect the planar surface presented in the solid joist assembly.

The member 16 is shaped in substantially an arrowhead configuration, providing a middle section 40, rectangular in shape and two backward directed legs 42a,b, rhomboid in shape, lying symmetrically from the middle section 40. The member 16 is also symmetrical in the opposite axis. This allows the multiple members to be nested, so that they can economically be cut or pressed from a single metal sheet. The nesting arrangement is shown in Figure 3 (b) . Once cut, the member 16 is folded at lines 52a,b between the middle section 40 and the legs 42a,b. By the nature of the material, the legs 42 will splay', lying naturally at around 15 degrees from the vertical. This is illustrated in Figure 3 (c) . The members 16 can be stacked in the splayed configuration for shipping. They can then simply be located upon a joist 14, with the middle section 40 spanning the width of the joist and the legs 42, locating at the respective sides 44 of the joist 14.

As previously presented, the width of the middle section 40 matches the width of the joist 14. This is typically 38mm or 45mm in solid timber joists. The member is initially held on the joist by nails 54, positioned through apertures 56a,b, located in the middle section 40. The apertures 56 may be 4mm holes drilled through the plate of the member when it is pressed (see Figure 3(b)) . Figure 3(d) illustrates the member 16 located on the joist 14 using the nails 54. The member 16 is positioned to provide a plate 58 close to the notch 36 to lie over the possible fracture lines (not shown) To provide sufficient reinforcement to the joist 14, the plate 58 is fixed to the surface 44 of the joist. Referring now to Figure 3(e), a fixing means between joist 14 and plate 58 is illustrated. Pressed through each plate 58 are stabs 60. Each stab 60 is principally cut as three sides of a rectangle, with the fourth side being a fold line. The rectangular section is then folded inwards, in this case towards the joist 14, to provide the stab 60. The stab 60 can be further shaped to provide a point is desired, but typically the width of the stab will be slim enough to allow the stab to be forced into the surface 44 of the joist 14, to act as a nail. An array of such stabs 60 are located across each leg 42a,b.

The degree of folding of each stab 60 is important in presenting the stab 60 in an ideally perpendicular configuration to the surface 44 of the joist 14. As the member 16 is splayed on the joist 14, stabs closer to the upper surface 38 of the joist 14 require to be arranged at a tighter angle to the plate 58. In the illustration, the first three rows of stabs are arranged at 75 degrees.

Additionally the lengths of the stabs can be varied to assist in positioning the member 16 and in forcing the stabs 60 into the timber joist 14. Thus stabs in these upper rows are also shorter in length.

An array of stabs 160 are shown in a reinforcing member 116, according to an alternative embodiment of the present invention, in Figures 4 (a) -(d) . Parts in Figure 4 similar to those in earlier Figures have been given the same reference numerals with the addition of 100, to aid clarity. Member 116 has a middle section 140 and legs 142, as for the previous embodiment. However, the legs 142 are now shaped to provide an additional portion 62. The portion 62 has a width of 70 mm extending from the fold line 152. A horizontal side section 64 of 45mm, gives the portion 62 a rectangular end sized to locate upon the elongate element 130 of the joist 114. The horizontal side section 64 meets the remaining leg 142 at a point or corner 66. This shape of member 116 provides additional support and easier mounting on the joist 114. Positioning is easier as the point 66 is arranged to locate on the notch 136 while the portion 62 fills the width of the elongate element 130. Thus the notch 136 has a wider spread of reinforcement surrounding it.

The portion 62 includes four rows of knuckle teeth, as are known in the art, for attaching the member 116 to the joist 114. Stabs 160 are provided on the remainder of the leg 142. Over the width, 115.4mm, of the leg 142 there are five staggered rows of fourteen stabs 160. Each stab 160 in this embodiment is formed by cutting two parallel lines representing the long sides of a rectangle; cutting a diagonal line from the one corner of the rectangle to the opposing corner; and folding the two created triangles inwardly over fold lines at the short sides of the rectangle. Effectively two stabs 160 are created by each rectangle cut. By cutting in this fashion and providing staggered rows, the maximum density of stabs 160 are created over the plate 158.

Reference is now made to Figures 5(a)-(e) of the drawings which illustrates a reinforcing member, given reference numeral 216, according to a further embodiment of the present invention. Like parts to those in the earlier Figures have been given the same reference numeral, but with the addition of 200, to aid clarity. In this embodiment the legs 242 are not in an arrowhead configuration, but are arranged vertically. The additional portion 262 is still in place, but the corner 266 is now a right-angle to exactly match and overlay with the right angle of the notch 236. The portion 262 also extends across the entire elongate element 230 to the front face 246 of the joist 214. In this way the middle section 240 is also longer to extend to the face 246 also.

An additional feature in this embodiment of the member 216 is a lip 68. The lip 68 is an extension of the portion 262 on the edge 264.

Edge 264 then becomes a fold line, such that when the stabs 260 are located in the surface 244 of the joist 214, the lip 68 rests on the lower surface 232 of the elongate element 230. The member 216 is symmetrical and this arrangement therefore provides two lips 68 providing additional support around the notch 236. In use, the lips 68 will lie between the abutting surfaces 226,232 of the wall 212 and joist 214, respectively.

An alternative embodiment based on the lip 68, is illustrated in Figures 6(a) and (b) . Like parts in the Figures have been given similar reference numerals but with the addition of 300. Reinforcing member 316, has a straight leg 342 arrangement with an additional portion 362 to lie over the elongate element 330 of the joist 314 (not shown) . Unlike the embodiment of Figure 5, however, member 316 has only a single lip 368 from one side 342a. The lip 368 extends from the fold line 364a across the majority of the element 330 making it as wide as the middle section 340. This is a non-symmetrical arrangement.

Accordingly, the strip forming the member 316 is initially folded only on one side at fold line 364a to form the lip 368 and then at the fold line 352a between the middle section 340 and the first leg 342a. Each fold is made to 90 degrees. The member 316 is then brought to the joist 314 and the leg 342a is located upon a first side 344a of the joist 314. The member 316 is positioned such that point 366a of the member 316 lies on the notch 336 of the joist 314.

Lip 368 will locate against surface 332. When in position, the member 316 is folded on line 352b and the stabs 360 on face 342b are forced into the face 344b of the joist 314. The size, shape and arrangement of stabs 360 can be as described herein before with reference to the earlier Figures.

A joist according to an embodiment of the present invention is shown in Figure 7 (a) . Again, like parts to those of the earlier Figures have been given similar reference numerals but with the addition of 400. Joist 414 is a piece of solid timber with a rectangular cross-sectional portion removed from the end to leave a notch 416, with a narrow elongate element 430. Reinforcing member 416 is a single rectangular plate including an array of stabs 460. A member 416 is located on each side 444 of the joist 414. The member 416 is located adjacent the notch 436. As the member 416 does not extend to the upper surface 438, the plate can be made of a thicker material if desired.

Figure 7(a) illustrates the joist 414 with a decking 70 laid on the surface 438. Referring to Figure 7(b), an exploded view of the assembly 410, joists 414 are arranged in parallel with the members 416 in place. A decking 70 is fixed over the joists 414 and extends to the face 446 proving a floor cassette. The supporting wall 412 is a profiled rim held on a standard timber frame kit 72.

An alternative embodiment of a timber joist including a reinforcing member according to the present invention is illustrated in Figure 8. Again, like parts to those of the earlier Figures have been given similar reference numerals but with the addition of 500. Joist 514 is a piece of solid timber with a rectangular cross-sectional portion removed from the end to leave a notch 516, with a narrow elongate element 530. Reinforcing member 516 comprises two pieces 74a,b. Pieces 74a,b are mirror images of each other and locate on either face 544 of the joist 514. Each piece 74 includes half the middle section 540a,b; a straight leg 542 with an additional section 562, both covered in an array of stabs 560; and a lip 568 extending from the edge 564 with a width equal to approximately half of that of the complete middle section 540.

In this example, pieces 74 are cut from sheet metal and initially folded at right angles on lines 552 and 564, facing in opposite directions. Additionally, the stabs 560 can be formed at this time.

Pieces 74 are then directed at the joist 514 from the sides so that all the stabs 560 can be arranged perpendicularly to the faces 542.

When located on the joist 514 it is preferable that the middle sections 540a,b meet.

Reference is now made to Figures 9 of the drawings which illustrate three configurations for top hanging a joist, according to embodiments of the present invention. Again, like parts to those of the earlier Figures have been given similar reference numerals but with the addition of 600. In each Figure, joist 614a,b,c is a solid timber joist having a portion removed at a first end to provide a notch 636a,b,c and a narrow elongate element 630a,b,c. While elements 630a,c are the same length, it is noted that the length of of element 630b is approximately half that of the others, thus a smaller portion has been removed from the joist 614b. Each Figure illustrates an alternative top-hung arrangement for the joists 614.

In Figure 9(a), the joist 614a is laid directly onto a timber frame 672a. In this arrangement the surface 632a of the underside of the element 630a abuts the upper surface 76a of a crossbar 78a of the timber frame kit 672a. A channel is not required in this arrangement.

In Figure 9(b), the joist 614b is laid upon an internal rimbeam 80a, with the surface 84a of the rimbeam 80a supporting the surface 632a of the joist 614b. An external rimbeam 82a is abutted to the internal rimbeam 80a. The external rimbeam 82a is taller than the internal rimbeam 80a, providing a face 86a against which the face 646b of the elongate element 630b can rest. The rimbeams 80a,82a are arranged on the crossbar 78b of the timber frame kit 672b. A channel 618b can be formed by using an internal rimbeam 80a, of the same height as the external rimbeam 82a, and locating a channel equal in dimensions to the elongate element 630b, therein.

Finally, in Figure 9(c), the joist 614c is laid upon the surfaces 84b,88a, of the internal and external rimbeams 80b,82b, respectively. In this arrangement, the rimbeams 80b,82b are of the same height and thus the load is transferred through the rimbeams 80b,82b to the timber frame 672c. A channel can be optionally used in this assembly.

Such top hung details, as illustrated in Figures 9, provide a number of advantages: * Structurally it is more stable than a bottom support -against overturning due to load; * Easy to locate joists; * Removes lintels from timber kits; * Assists with thermal bridging; * No need to line up joists with timber studs; * No need for double head binders; * If putting straight onto timber kit do not need rimbeam; * Helps minimise shrinkage.

The principle advantage of the present invention is that it provides a solid timber joist assembly where a solid timber joist is in a top hung configuration.

A further advantage of the present invention is that it provides a timber joist wherein a reinforcing member is included to provide an engineered timber joist with a strength comparable to a timber joist of similar overall dimensions.

A still further advantage of the present invention is that it provides a solid timber joist assembly wherein the joist can be fitted with the reinforcing member off-site so that no mechanical connections are required to be made when the joist is located to the support, on-site.

It will be appreciated by those skilled in the art that various modifications may be made to the invention herein described without departing from the scope thereof. For example, while reference has been made to upper and lower surfaces and the figures illustrate an elongate element at the top of the joist, the elongate element may be formed at any location on the end face of the joist, such as from the lower end. Equally, the elongate element could be arranged away from the top and bottom ends, providing a mortise and tenon arrangement. The channel in the supporting wall would then be on the side facing the joist. Two notches would also be present on each side of the joist. The reinforcing members may be any shape and size as long as they provide bridging over the fracture lines in the neighbourhood of each notch. In addition, the elongate element may be located onto or below any type of structural supporting member.

Additionally, any suitable fixing means may be used to hold the reinforcing member to the joist.

Claims

CLAIMS1. A solid timber joist assembly comprising a first supporting member, the first supporting member including a channel located therein with a base of the channel defining a first abutting surface; a solid timber joist, the joist having a portion of an end removed to provide an elongate element protruding there from, the element including a second abutting surface created by removal of the portion and a notch created where the second abutting surface meets the joist; and a reinforcing member located in relation to the notch such that when the element is located in the channel, the abutting surfaces meet, a load is applied across the elongate element and the reinforcing member prevents failure of the joist local to the notch.
2. A solid timber joist assembly according to claim 1 wherein, the channel is of square profile and a depth of the channel is Q2O approximately equal to a width of the element.
3. A solid timber joist assembly according to claim 1 or claim 2 wherein, the reinforcing member comprises a plate including fixing means to attach the plate to a surface of the joist local to the notch.
4. A solid timber joist assembly according to claim 1 or claim 2 wherein, the reinforcing member is a screw located through the joist from an upper surface to pass adjacent to the notch.
5. A solid timber joist assembly according to claim 3 wherein, the plate is substantially rectangular and includes an elongate section sized to locate upon the elongate element with the remaining section of the plate locating on a surface of the joist adjacent the notch.
6. A solid timber joist assembly according to claim 3 or claim 5 wherein, a pair of plates are located, one on each side of the joist.
7. A solid timber joist assembly according to any one of claims 3, 5 or 6 wherein, each plate includes a lip arranged to extend perpendicularly from an edge there upon and locate upon the second abutting surface.
8. A solid timber joist assembly according to claim 7 wherein, the lip extends along a length of the elongate element.
9. A solid timber joist assembly according to claim 7 or claim 8 wherein a lip is also arranged to extend over the upper surface of the joist.
10. A solid timber joist assembly according to any one of claims 6 Q to 9 wherein, the reinforcing member comprises a single piece plate having a mid-section locating upon the upper surface of Q2O the joist and two opposing end sections which form the plates Q on each side of the joist.
11. A solid timber joist assembly according to any one of claims 3 or 5 to 10 wherein the fixThg means comprise a nail located through an aperture in the plate and there are a plurality of apertures are located through the plate.
12. A solid timber joist assembly according to any one of claims 3 or 5 to 11 wherein the fixThg means comprise a plurality of stabs, wherein each stab is a prong, cut and bent from the plate.
13. A joist for use in timber frame building construction, the joist comprising an elongate rectangular member of substantially rectangular cross-section, wherein at a first end there is removed at least one portion of the member to provide an elongate element protruding therefrom and at least one reinforcing member is arranged on the joist local to the at least one removed portion.
14. A joist for use in timber frame building construction according to claim 13 wherein, the joist is a solid timber joist.
15. A joist for use in timber frame building construction according to claim 13 or claim 14 wherein, a width of the elongate element is less than half a width of the joist.
16. A joist for use in timber frame construction according to any one of claims 13 to 15 wherein, the reinforcing member comprises a plate including fixing means to attach the plate to a surface of the joist.
17. A joist for use in timber frame construction according to claim 16 wherein, the plate is substantially rectangular and includes an elongate section sized to locate upon the elongate C element with the remaining section of the plate locating on a surface of the joist adjacent the removed portion. Q2Oo
18. A joist for use in timber frame construction according to claim 16 or claim 17 wherein, a pair of plates are located, r one on each side of the joist. r19. A joist for use in timber frame construction according to any one of claims 16 to 18 wherein, each plate includes a lip arranged to extend perpendicularly from an edge there upon and locate upon a surface of the joist created when the portion is removed.20. A joist for use in timber frame construction according to claim 19 wherein, the lip extends along a length of the elongate element.21. A joist for use in timber frame construction according to claim 20 wherein a lip is also arranged to extend over the upper surface of the joist.22. A joist for use in timber frame construction according to any one of claims 13 to 21 wherein, the reinforcing member comprises a single piece plate having a mid-section locating upon the upper surface of the joist and two opposing end sections which form the plates on each side of the joist.23. A joist for use in timber frame construction according to any one of claims 16 to 22 wherein, the fixing means comprise a nail located through an aperture in the plate and there are a plurality of apertures are located through the plate.24. A joist for use in timber frame construction according any one of claims 16 to 23 wherein the fixing means comprise a plurality of stabs, wherein each stab is a prong, cut and bent from the plate.25. A joist for use in timber frame construction according to Q claim 24 wherein one or more of the stabs lie perpendicular to the plate.Q 26. A joist for use in timber frame construction according to claim 24 or claim 25 wherein, the stabs are angled from the plate at about 75 degrees.27. A reinforcing member for use with a joist in a timber joist assembly, the member comprising a base plate having first and second plates extending therefrom and means for connecting the member to a timber joist.28. A reinforcing member for use with a joist in a timber joist assembly according to claim 27 wherein, the member is constructed of a thin gauge metal which can be pressed and folded.29. A reinforcing member for use with a joist in a timber joist assembly according to claim 27 or claim 28 wherein, the member is of single piece construction having two fold lines to create the first and second plates.30. A reinforcing member for use with a joist in a timber joist assembly according to claim 29 wherein, the fold is made so that the first and second plates are splayed.31. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 30 wherein, the base plate is substantially rectangular and sized to locate across a typical solid timber joist on it's smaller dimensLon.32. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 31 wherein, the base plate includes apertures to facilitate the fixing of the member to a joist by locating nails or other suitable fixings there through.33. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 32 wherein, the Q first and second plates are mirror images of each other.Q2O 34. A reinforcing member for use with a joist in a timber joist Q assembly according to any one of claims 27 to 33 wherein, the first and second plates are larger than the base plate.35. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 34 wherein, the first and second plates are rhomboid in shape.36. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 34 wherein, the first and second plates are substantially rectangular.37. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 35 wherein, the plates include an elongate section protruding from a side of the rectangular section.38. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 37 wherein, each plate includes a lip arranged to extend perpendicularly from an edge there upon.39. A reinforcing member for use with a joist in a timber joist assembly according to claim 38 wherein, the lip extends from the elongate section.40. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 27 to 39 wherein, the first and second plates include fixing means.41. A reinforcing member for use with a joist in a timber joist assembly according claim 41 wherein, the fixing means comprise a nail located through an aperture in the plate.42. A reinforcing member for use with a joist in a timber joist assembly according claim 42 wherein, a plurality of apertures Q is located through the plate.43. A reinforcing member for use with a joist in a timber joist assembly according to claim 40 wherein, the fixing means is integral to the plate.44. A reinforcing member for use with a joist in a timber joist assembly according to claim 43 wherein, the fixing means comprise a plurality of stabs, and wherein each stab is a prong, cut and bent from the plate.45. A reinforcing member for use with a joist in a timber joist assembly according to claim 44 wherein, the stabs are arranged to lie perpendicular to the plate.46. A reinforcing member for use with a joist in a timber joist assembly according to claim 44 wherein, the stabs are angled from the plate.47. A reinforcing member for use with a joist in a timber joist assembly according to claim 46 wherein, the angle is about 75 degrees.48. A reinforcing member for use with a joist in a timber joist assembly according to claim 46 wherein, the stabs are arranged such that when a splayed member is located over a joist, stabs positioned closest to the base plate will face the joist substantially perpendicularly.49. A reinforcing member for use with a joist in a timber joist assembly according to any one of claims 44 to 48 wherein, lengths of the stabs vary across the first and/or second plate, being smaller in length towards the base plate. Co