GB2487969A

GB2487969A - Structural stud channel frame member for reducing thermal transfer

Info

Publication number: GB2487969A
Application number: GB201102456A
Authority: GB
Inventors: Oliver Rogan
Original assignee: ADVANCED COLD FORMED SECTIONS Ltd
Current assignee: ADVANCED COLD FORMED SECTIONS Ltd
Priority date: 2011-02-11
Filing date: 2011-02-11
Publication date: 2012-08-15
Also published as: GB201102456D0

Abstract

The frame member 10 comprises a rigid elongate body portion, a number of holes 20 formed through the body and bridging elements 18 going across the holes from one end of a hole to the other. The holes may be narrow slots; the bridging elements may be unitary with the body and preferably couple one narrow end of a slot to a second end of said slot. The bridging elements may protrude from one face of the body and be arranged in several rows with several holes. The frame member may be a profiled section member such as a C, Z, L or I frame member cold formed from steel and be part of a wall stud. The bridging members/holes may be formed by cutting two sides of a hole and then embossing the frame to form a protruding bridge. Also claimed is a method for making the frame member.

Description

Frame Member

Background

Thermal insulation in a building is an important because it reduces unwanted thermal transfer between the interior and exterior of the building.

Many modem buildings include stud walls. A stud wall in the form of a cold formed steel section frame can be load bearing or non-load bearing. Such a wall generally includes a number of rigid, elongate frame members, such as building studs that are orientated vertically between the floor and the ceiling. An outer wall part, such as insulated board, is connected to one side of the studs by screws, or other suitable mechanical fixing means.

An inner wall part, such as plasterboard, is connected to the other side of the studs in a similar manner. The studs connect the inner and outer wall parts and, accordingly, the width of the studs generally governs the size of a cavity between the inner and outer wall parts.

Insulation material may be provided in the cavity between the inner and outer wall parts to reduce unwanted thermal transfer between the wall parts. However, the screws or the like that are used to connect the wall parts to the studs permit thermal bridging to occur through the body of the stud. This is known as "cold bridging".

It is known that providing holes through C section studs reduces the effects of cold bridging by reducing heat flux across the studs. The holes form air gaps, across which it is more difficult for heat to pass.

It would however be beneficial if an improved frame member, such as a wall stud, was available.

Summary

According to a first aspect of the present invention, there is provided a frame member suitable for a stud wall, the frame member including: a rigid, elongate body portion; one or more holes formed through the body portion; and one or more rigid bridging elements, a bridging element being arranged to bridge one side of a respective one of the holes to another side of the respective one of the holes. Thus, a frame member according to embodiments of the present invention includes one or more holes arranged to minimise cold bridging, to achieve the required thermal performance of a building envelope, without adversely affecting the structural performance of the frame member due to the one or more bridging elements.

A plurality, or each, of the bridging elements may be arranged to bridge one side of a respective one of the holes to another, possibly opposite, side of the respective one of the holes.

One or more of the bridging elements may be unitary with the body. Such embodiments may produce less waste and/or increase manufacturing efficiency.

One or more of the holes may be elongate and one or more of the bridging elements may each couple a first narrow side of an elongate hole to a second narrow side of the elongate hole.

The longitudinal axis of at least some of the elongate holes may extend generally parallel to the longitudinal axis of the body portion. In some embodiments, this improves the reduction of heat flux laterally through the body of the frame member.

The bridging elements may be elongate and may extend along the body, which in some embodiments means the general pathway defined by the bridging element will be less than 45Q with respect to the longitudinal axis of the body and preferably less than 30°, less than 20°, less than 15°, less than 5° or generally parallel with respect to the longitudinal axis of the body. In some embodiments, this reduces the likelihood of a bridging element enabling heat flux to circumvent the hole it bridges in a simple manner.

The body may be generally planar, having first and second major faces that face in opposite directions to one another, and the one or more bridging elements are each arranged to protrude from the same one of the first and second major faces.

The frame member may include a plurality of holes and a plurality of bridging elements.

The holes may be arranged in an array including a plurality of rows.

Each row may include a plurality of holes and a plurality of bridging elements.

The plurality of holes may be arranged such that a straight line pathway extending laterally through the body from one side to another intersects one or more of the holes.

The frame member may be one or more of the following: a profiled-section frame member, such as a C section, Z section, L section or I section frame member; a cold formed member, such as a cold formed steel section; and a wall stud, track or the like.

The frame member may be arranged to be a load bearing frame member for inclusion in, for example, a load bearing stud wall.

hi accordance with a second aspect of the present invention, there is provided a method of forming a frame member, the method including the steps of: providing a rigid, elongate body portion; forming one or more holes through the body portion; and forming one or more bridging elements, a bridging element being arranged to bridge one side of a respective one of the holes to another side of the respective one of the holes.

The step of forming one or more bridging elements may be provided by embossing the body portion to deform the body portion to create unitary bridging elements.

The step of forming one or more holes through the body portion may include making two cuts in the body portion for each hole. The cuts may be made prior to the step of embossing or generally sequentially therewith.

The one or more holes may be elongate.

The step of forming one or more holes through the body portion may include forming a plurality of holes through the body portion.

The plurality of holes may be arranged in an array including a plurality of rows.

Brief Description of the Drawings

By way of example only, certain embodiments of the invention will now be described by reference to the accompanying drawings, in which: Figure 1 is a partial perspective view of frame member according to a first embodiment of the present invention; Figure 2 is a partial cross section view of frame member of Figure 1 through the axis A-A; Figure 3 is a partial plan view of the frame member of Figure 1; Figure 4 is a front view of the frame member of Figure 1; Figure 5 is a partial perspective view of frame member according to a second embodiment of the present invention; Figure 6 is a partial cross section view of frame member of Figure 5 through the axis A-A; Figure 7 is a partial perspective view of frame member according to a third embodiment of the present invention; Figure 8 is a partial cross section view of frame member of Figure 7 through the axis A-A; Figure 9 is a partial perspective view of frame member according to a fourth embodiment of the present invention; Figure 10 is a partial cross section view of frame member of Figure 9 through the axis A-A; Figure 11 is a partial perspective view of frame member according to a fifth embodiment of the present invention; Figure 12 is a partial cross section view of frame member of Figure 11 through the axis A-A; and Figure 13 is a flow diagram of a method of forming a frame member according to an embodiment of the present invention.

Detailed Description

Referring to Figure 1 of the accompanying drawings, a partial perspective view of a frame member 10 according to a first embodiment of the present invention is shown. The frame member in this embodiment is a wall stud 10 is of the type suitable for a stud wall, or partition wall. However, in other embodiments the frame member may be any type of rigid section, such as a cold formed steel section of any suitable section type, a wall stud, a head or floor track, or mezzanine floor cassette section.

The stud 10 in the illustrated embodiment is elongate and formed of a rigid material, such as steel. The stud 10 in this embodiment is unitary. The stud 10 has a central, generally planar web 12, or body portion 12, and a pair of generally planar side portions 14a, 14b.

Fach side portion 14a, 14b extends from a respective side region of the body in a common direction. The side portions 14a, 14b are configured to be generally orthogonal with respect to the body portion 12. The free sides of the side portions 14a, 14b are bent inwardly towards one another to form a pair of flanges 1 6a, 1 6b configured to be generally orthogonal with respect to the side portions 14a, 14b. The stud 10 is therefore what is known in the art as a "C" section stud and may be formed by any conventional process, such as cold rolling.

Referring additionally to Figures 2, 3 and 4, the body 12 of the stud 10 includes a plurality of holes 20 arranged in an array. The purpose of the holes 20 is to reduce the effects of cold bridging across the stud 10 by reducing heat flux across the stud 10. The holes 20 form air gaps, across which it is more difficult for heat to pass. Put another way, the holes form thermally broken sections that increase the thermal path across the stud 10.

In this embodiment, the holes 20 are longitudinal slots 20 having relatively longer sides than relatively narrower ends. The length of the slots is slightly less than length L shown in Figure 3. The width W of the slots is also shown in Figure 3. The longitudinal slots 20 are arranged such that each extends generally parallel with respect to the longitudinal axis of the stud 10. The slots 20 are arranged into five discrete, parallel rows, each row extending along the body 12 in a generally parallel manner with respect to the longitudinal axis of the stud 10. There is a land region 12a between each adjacent slot 20 in a row.

Each land region 12a has a length S, which is preferably less than length L. The slots 20 of one row are staggered relative to the slots 20 of an adjacent row, such that an imaginary line extending laterally through the body 12 and passing through a land region 12a of one row intersects a slot within a different row. In the illustrated embodiment, such an imaginary line would intersect either two or three slots 20, depending on the land region 12a through which it extends. In some embodiments, the slots 20 are arranged such that an imaginary line extending laterally through the body 12 at any point along the body 12 and passing through a land region l2a of one row intersects a slot within a different row.

The stud 10 also includes a plurality of elongate bridging elements 18. Each bridging element is mechanically coupled to the body 12 and spans a hole 20. Preferably, the bridging elements 18 are arranged such that they do not provide a simple pathway for thermal transfer across the respective holes 20 that they bridge. In this regard, one or more of the bridging elements 18 may be orientated at an angle of less than 45° with respect to the longitudinal axis of the body 12. Preferably, the bridging elements 18 may be orientated at an angle of less than 30°, less than 20°, less than 15°, less than 5° or generally parallel with respect to the longitudinal axis of the body 12. A bridging element preferably has two free sides i.e. side which are not coupled to the body 12.

In the illustrated embodiment, each bridging element 18 bridges the narrow end regions of a respective slot 20. Thus, each bridging element 18 provides a rigid mechanical linkage between a region of the body 12 at one end of a respective slot and a region of the body 12 at another end of the respective slot 18. Put another way, a bridging element 18 provides a rigid mechanical linkage between adjacent land regions 12a in a row of slots 20. The holes, or perforations, formed in known C section studs potentially reduce the load carrying capacity of the studs in compressing and bending. One function of the bridging elements 18 is to increase the rigidity of the stud 10 relative to a perforated stud having no bridging elements 18. Thus, restrictions in terms of the number and sizing of slots 20 may be lessened relative to a stud having no bridging elements 18. Thus, a stud according to embodiments of the present invention may have the same or better stiffness than known building studs, in addition to having the same or better thermal insulation in terms of cold bridging.

The bridging elements 18 in the illustrated embodiment each have a raised, planar central portion 1 8b that is generally parallel to the body portion 12, and ramped planer ends 1 8a, 1 8c that extend from the central portion 1 8b to the land portions 12a on either side of the slot 20. When viewed from the side, the bridging elements 18 are generally semi.-hexagonal. This shape enhances the local compression resistance of the body portion 12.

The bridging elements 18 each project from the body 12 in a common direction, into the stud 10 (i.e. towards the flanges 16a, 16b). This has an advantage that that plasterboard or the like can be coupled, flush to the back of the body 12.

The bridging elements 18 may be coupled to the body 12 by any suitable means, such as by welding. However in preferred embodiments of the present invention the bridging elements 18 are integrally formed with the body 12 such that the body 12 and bridging elements are unitary. This can be achieved by a process such as embossing, in which the projections of an embossing roller (not shown) deform the body 12 to create the bridging elements 18. The projections of the embossing roller may also slice the sides of the slots 20, or this may be done in an earlier processing stage. Embodiments of the present invention where at least some of the bridging elements 18 are unitary with the body portion 12 have the advantage of reducing waste created in manufacturing the perforated studs, because the part of the body 12 displaced to create the slots 18 are utilised to form the respective bridging elements 18, rather than being discarded as is the case in the prior art.

Such embodiments may also have the advantage of enabling increased manufacturing efficiency because deforming the body 12 to create the bridging elements 18 is simpler than punching out pieces of the body 12 to form the slots 18 because the body parts are only being deformed, rather than being sheared free.

Referring to Figures 5 and 6 of the accompanying drawings, a partial perspective view of a stud 30 according to a second embodiment of the present invention is shown. The stud 30 of this embodiment is similar to the building stud 10 of the first embodiment and like parts have been given the same reference numerals.

The stud 30 according to the second embodiment differs to the building stud 10 of the first embodiment in that the slots 20 and bridging elements 18 are arranged in three rows, rather than five, and in that the bridging elements 18 project outwardly from the body portion 12 (i.e. away from the flanges 16a, 16b). In some embodiments this may add to the compression resistance of the body portion 12.

Referring to Figures 7 and 8 of the accompanying drawings, a partial perspective view of a stud 40 according to a third embodiment of the present invention is shown. The building of this embodiment is similar to the stud 30 of the second embodiment and like parts have been given the same reference numerals.

The stud 40 according to the third embodiment differs to the stud 30 of the second embodiment in that the bridging elements 18 each define a ramped projection having a pair of planar sides 1 8d, 1 8e leading to an apex there between. When viewed from the side, the bridging elements 18 are generally triangular without having a base.

Referring to Figures 9 and 10 of the accompanying drawings, a partial perspective view of a stud 50 according to a fourth embodiment of the present invention is shown. The building stud 50 of this embodiment is similar to the building stud 40 of the third embodiment and like parts have been given the same reference numerals.

The stud 50 according to the fourth embodiment differs to the stud 40 of the third embodiment in that the bridging elements 18 each define an actuate, or rounded, projection having a radius R which is greater than the slot length L. Referring to Figures 11 and 12 of the accompanying drawings, a partial perspective view of a stud 60 according to a fifth embodiment of the present invention is shown. The stud of this embodiment is similar to the stud 50 of the fourth embodiment and like parts have been given the same reference numerals.

The stud 60 according to the fifth embodiment differs to the stud 50 of the fourth embodiment in that the bridging elements 18 are wider.

Figure 13 shows a flow diagram of a method of forming a stud according to an embodiment of the present invention. The method begins at step 70 by providing a rigid, elongate body portion of a stud. At step 72 one or more holes are formed through the body portion. At step 74 one or more bridging elements are formed, a bridging element being arranged to bridge one side of a respective one of the holes to another side of the respective one of the holes. At step 78 optional additional method steps may be carried out, such as cold rolling the stud into shape, such as "C" section.

The method may utilise an embossing tool including a roller upon which are mounted a plurality of projections shaped to define the bridging elements 18. The method may thus include embossing the body portion to deform the body portion to create unitary bridging elements.

The method may include making two cuts in the body portion for each hole. This may occur prior to, or contemporaneously with, the step of forming the bridging elements.

The method may be used to form a stud according to any of the embodiments of the present invention.

In one specific example, the steel or section is put through a pair of driven rollers arranged as an upper and lower roller. Fully adjustable guide rollers may be used to direct the material into the rollers.

The tooling on the bottom roller includes a series of shaped, hardened D2 tool steel inserts that arc machined into retaining pockets around the circumference of the bottom roller.

The number of inserts would be to suit the embossed pitch of bridging elements 18 in the finished product.

The top roller includes a series of slitting cutters that may be accurately spaced by precision machined spacers. The number of cutters and spacers can be varied to allow for any variation in terms of the number of rows of embossing, such as between 2 and 26 rows of bridging elements 18.

As the profile bottom roller insert makes contact with the material, each side of the insert is opposed by the edge of the top roller acting as a slitting cutter, which would slit the material for the length of engagement. The material that is raised in the base will thus take the shape of bottom roller inserts, to form the bridging elements 18.

The embodiments described herein are specific examples and many modifications will be apparent to a skilled person without departing from the inventive concept of providing a stud having a rigid, elongate body portion, one or more holes formed through the body portion and one or more rigid bridging elements, a bridging element being arranged to bridge one side of a respective one of the holes to another side of the respective one of the holes. Examples of such modifications are: Although in the described embodiments the holes are rectangular in shape, in other embodiments the holes may be of any suitable shape and orientated in a suitable manner.

Although in the described embodiments the stud includes a plurality of holes, in other embodiments the stud may include one or more holes, arranged in any number of rows, or in some embodiments the holes may be arranged in another suitable manner. In some embodiments the stud may include more than 10 row, more than 20 rows, more than 30 rows, more than 40 rows or more than 50 rows.

Although in the described embodiments the stud includes a bridging element for each hole, in other embodiments the stud may include one or more holes that are not bridged by a bridging element.

Although in the described embodiments the bridging elements longitudinally bridge the slots, in other embodiments the bridging elements may be of any suitable configuration.

Although in the described embodiments the stud is a "C" section stud, in other embodiments the stud could have a different configuration, such as "I" section, "L" section "Z" section or the like.

Although in the described embodiments the stud is formed of steel, in other embodiments the stud could be made of any type of material that conducts heat and has the necessary characteristics for a building stud.

A stud according to embodiments of the invention may be any suitable width, such as 100mm, 150mm, 200mm, or 250mm.

It should be noted that the term "rigid" as used herein is intended to mean generally or substantially rigid. The term "planar" is intended to define the overall profile of a part and does not exclude the part in question including ridges or the like.

Claims

Claims 1. A frame member including: a rigid, elongate body portion; one or more holes formed through the body portion; and one or more rigid bridging elements, a bridging element being arranged to bridge one side of a respective one of the holes to another side of the respective one of the holes.
2. A frame member according to claim 1, wherein one or more of the bridging elements are unitary with the body.
3. A frame member according to claim 2, wherein one or more of the holes are elongate and one or more of the bridging elements each couple a first narrow side of an elongate hole to a second narrow side of the elongate hole.
4. A frame member according to claim 3, wherein one or more of the elongate holes and/or the bridging elements are arranged such that their longitudinal axis is orientated at an angle of less than 450 with respect to the longitudinal axis of the body portion.
5. A frame member according to any preceding claim, wherein the body is generally planar, having first and second major faces that face in opposite directions to one another, and the one or more bridging elements are each arranged to protrude from the same one of the first and second major faces.
6. A frame member according any preceding claim, including a plurality of holes and a plurality of bridging elements.
7. A frame member according to claim 6, wherein the holes are arranged in an array including a plurality of rows.
8. A frame member according to claim 7, wherein each row includes a plurality of holes and a plurality of bridging elements.
9. A frame member according to claim 8, wherein the plurality of holes are arranged such that a straight line pathway extending laterally through the body from one side to another intersects one or more of the holes.
10. A frame member according to any preceding claim, wherein the frame member is one or more of the following: a profiled-section frame member, such as a C section, Z section, L section or I section frame member; a cold formed member, such as a cold formed steel section; and a wall stud, track, mezzanine floor cassette component, or the like.
11. A method of forming a frame member, the method including the steps of: providing a rigid, elongate body portion; forming one or more holes throngh the body portion; and forming one or more bridging elements, a bridging element being arranged to bridge one side of a respective one of the holes to another side of the respective one of the holes.
12. A method according to claim 11, whereby the step of forming one or more bridging elements is provided by embossing the body portion to deform the body portion to create unitary bridging elements.
13. A method according to any of claims 11 and 12, wherein the step of forming one or more holes throngh the body portion includes making two cuts in the body portion for each hole.
14. A method according to any of claims 11 to 13, whereby the one or more holes are elongate.
15. A method according to any preceding claim, whereby the step of forming one or more holes throngh the body portion includes forming a plurality of holes through the body portion.
16. A method according to claim 15, whereby the plurality of holes are arranged in an array including a plurality of rows.
17. A method according to any of claims 15 and 16, whereby the plurality of holes are arranged such that a straight line pathway extending laterally through the body from one side to another intersects one or more of the holes.