GB2488100A - Recessed acoustic cross battening - Google Patents

Abstract

A bracing system for use in timber building construction where support members such as joists, studs and trusses are arranged in a framework with at least one batten arranged to overlap at least two support members. The support members each have a recess located in a surface thereof and the batten is dimensioned to sit within the recesses so that the battens do not have to be removed when the framework is in position. The recesses can be sized to match the dimensions of the batten or allow the batten to stand proud and be used to support panels located over the framework. The recesses can be arranged to provide cross bracing.

Description

SPACING SYSTEM

The present invention relates to building construction and in particular, though not exclusively, to an improved bracing system for floors, walls and roof constructions.

In building construction, timber is typically used as a framework upon which other component parts of the build are affixed. For example, timber joists provide a framework for ceilings or floors; timber studs provide uprights against which sheets of material such as plasterboard can be affixed to create walls; and timber trusses provide the fixed structure for making up a roof. To strengthen the timber framework, bracing is used. Bracing usually takes the form of timber battens nailed to a surface of the framework, the battens being arranged to link across the timber support members and thereby stiffen i.e. brace the structure. Bracing is always surface mounted unless it is used as a strongback in open web assemblies, it is then run through the voids created by the open nature of the joist itself.

However, while the bracing strengthens the framework during construction, there is a major disadvantage in its use as it must be removed to allow for the installation of supported components, e.g. floor decking, plasterboard etc. The removal of the battens takes up valuable build time while there disposal or transport for re-use, adds to build costs.

It is therefore an object of the present invention to provide a bracing system which overcomes at least some of the

disadvantages of the prior art.

It is a further object of the present invention to provide a bracing system which does not require to be removed for the installation of supported components.

According to a first aspect of the present invention there is provided a bracing system for use in construction, comprising: a plurality of support members arranged in a framework and at least one batten arranged to overlap at least two support members, wherein the support members each have a recess located in a surface thereof and the batten is dimensioned to sit within the recesses.

By recessing the batten into the support it allows bracing to remain as a permanent part of the structure.

Preferably, a depth of the recess is equal to a depth of the batten. In this way, the batten and support member are at the same finished level which allows for the fixing of nails etc into the batten to provide additional support for the supported components.

Preferably, a width of the recess is approximately equal to a width of the batten. In this way the batten is a close fit in the recess and the recessed batten can be used to align the support members in the framework.

Preferably there are a plurality of battens. This provides additional rigidity, preventing the braced framework from s kew.

Preferably, the support members are solid timber and the recesses are machined from a first side of the member to a second side of the member. The recess may be orthogonal to the support member. Alternatively, the recess may be diagonally arranged to the support member. Such an arrangement provides for cross bracing. The support members may be joists, studs or other timber components as are known in the art.

Optionally, the system may further comprise supported components, the supported components being affixed over the framework and recessed battens. Preferably, the supported components are panel products such as plywood or plasterboard as is known in the art.

Alternatively, a depth of the recess may be less than a depth of the batten. In this way, the supported components will stand proud of the framework. Preferably also, the battens are acoustic battens. In this way, the supported component may be a floor which will have improved acoustic performance.

Advantageously, the joists and battens may be treated with a water repellent. In this way, the joists will not suffer from shrinkage.

Advantageously, the joists and battens may be treated with a fire retardant. In this way, the assembly can have an improved fire rating.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings of which: Figure 1 is a schematic illustration of a bracing system according to an embodiment of the present invention; Figure 2 is a schematic illustration of a support member and a batten according to a further embodiment of the present invention; and Figures 3(a)-(c) are schematic illustrations of a separating floor including bracing systems according to a further embodiment of the present invention.

Referring initially to Figure 1, there is illustrated a bracing system, generally indicated by reference numeral 10, in which joists l2a-c are braced together by battens l4a,b located within recesses l6a-c,l8a-c, according to an embodiment of the present invention.

Joists 12 are solid timber joists as may be found in floor construction. The joists could be I joists as are known in the art. Joists 12 are laid out parallel to each other in spaced apart relationship. On an upper surface 20a-c, of each joist 12, there is machined recesses 16a-c, l8a-c. The recesses 16,18 are spaced apart over the surface 20.

A recess 16 is also illustrated in Figure 2, which shows an exploded side view of the joist 12 and batten 14. Recess 16 is of rectangular cross-section and is formed as a slot from a first side 22 (out of view) to a second side 24 of the joist 12. Recess 16 has a base 26 and side walls 28,30 respectively.

Batten 14 is a plank of solid timber. It also has a rectangular cross-section providing a top surface 32, bottom surface 34 and side walls 36,38 respectively. As shown in Figure 1, battens l4a,b have a length extending across the framework of joists 12a-c. Battens l4a,b are also spaced apart in parallel relation, at a distance equal to the separation distance of neighbouring recesses 16a-c,18a-c on a joist 12a-c.

It is noted that the base 26 of the recess 16 and the lower surface 34 of the batten 14 have the same dimensions.

Additionally the depth of the side walls 28,30, of the recess 16 and the depth of the side walls 36,38 of the batten 14 also match. Thus with the battens 14a,b located in the recesses 16a-c,18a-c, there is a close fit and the upper surface 32 of the battens 14 is flush with the upper surfaces 20a-c of the joists 12a-c.

In use, the joists 12 are laid out in spaced apart relation.

The battens 14 are then located in the recesses 16. As the dimensions of the battens 14, match those of the recesses 16,18, the insertion of a batten 14 across the joists 12a-c, will bring the joists l2a-c, into positive alignment. A nail or other fastener (not shown) can be inserted through the batten 14 and into the joist 12 to hold the framework together for transportation, lifting etc. With the battens 14 in place, the system 10 provides a framework of joists having both restraint and rigidity.

As the joists 12 are braced together, the entire framework can be transported and lifted as a single unit, so speeding up on site construction time. On site the system 10, is lifted and positioned where desired. No specialist tradesmen are reguired for installation as the joists 12 can be fitted by known techniques for floor cassettes. When in position, the battens 14 are left in position and neither detached, nor removed.

This provides a rigidity to the final construction, not found in the prior art. Indeed, in the initial plans for the construction the contribution from the incorporated bracing can be taken account of in the calculated design.

With the system 10 in place, panel prcducts such as OSE, plank, decking can be fastened to the joists 12 and the battens 14. This is illustrated in Figure 2, where a panel 40 is brought up to the upper surface 20 of the joist 12. As the batten 14 resides entirely within the recess 16, the lower surface 42 of the panel 40 will abut the upper surface 20. The panel 40 can then be nailed or otherwise affixed to the joists 12. Additionally, as the surface 32 of the batten 14 is cc-planar to the surface 20 of the joist 12, additional fixings to the panel 40, can be made through the battens 14. This provides a form of bracing to the panel 40 also.

In masonry and timber frame building construction, floors and ceilings are typically assembled by locating joists across the span between masonry or timber frame either supported directly or via joist hangers. A ceiling is created by fixing gypsum board to the underside of the joists. A floor is created by fixing layered decking on the upper side of the joists.

For sufficient sound insulation the floor and ceiling must be isolated from each other. Accordingly, ceiling joists are first arranged on the structure with the floor joists being arranged above the ceiling joists, to create an insulation gap there between. In some constructions, the ceiling and floor joists are interleaved to reduce the space reguired between the floor and ceiling. These timber engineered floors and independent ceilings are typically assembled on site.

Engineered timber floor cassettes have been developed comprising joists, typically I joists or open web joists, with the decking, such as plywood or chipboard, pre-installed. The decking acts to brace the joists. Lifting straps are built-in to the cassettes so that, with the use of a crane, they can be lifted both for transportation to the site and erection on-site. The ceiling, however, are still currently constructed on site by skilled tradesmen cutting joists to size, locating them on joist hangers and then attaching gypsum board to create a ceiling.

Systems comprising both a ceiling cassette and a floor cassette have been presented in Applicants co-pending applications GB 1019659.0 and GB 1100869.5. In these applications the decking or plasterboard is attached directly to the joists to act as a brace while forming the floor or ceiling. Surface mounted bracing is also suggested for the ceiling cassette.

The advantages of the recessed brace of the present invention can be incorporated into these floor and ceiling cassettes.

Reference is now made to Figures 3(a)-(c) of the drawings which illustrate a separating floor, generally indicated by reference numeral 50, formed from a structural floor 52 (Figure 3(a)) and an independent ceiling 54 (Figure 3(c)) . Both the structural floor 52 and the independent ceiling 54 comprise bracing systems according to embodiments of the present invention.

Floor 52 can be considered as an engineered timber floor cassette 56. Floor cassette 56 is manufactured from a series of rectangular cross-sectional floor joists 58 arranged in parallel. The joists 58 are typically I joists or solid timber. Each joist 58 has a series of recesses 60 machined in an upper surface 62. Acoustic battens 64 are arranged to span the joists, aligning and fixing them together, by insertion in the recesses 60. Each acoustic batten 64 is formed from a solid plank of timber having a width matching the width of the recess 60. The batten 64 is deeper than the depth of the recess 60 and so sits proud of the upper surface 62 of the joist 58. The upper edge 66 of the batten 64 includes a dampener, to assist in the acoustic isolation of the decking 70 to the joist 58. Attached to the battens 64, at the upper edge, is the lower side 68 of decking 70. Decking 70 is applied as a sheet across the joists 58, affixed to the battens 64, which are in turn fixed to the joists 58. Decking provides a floor to the floor cassette 56. The decking 70 is typically formed of plywood or ohipboard. Decking 70 can extend around the sides of the cassette 56. Attachments (not shown) can be incorporated so that the cassette 56 can be lifted by a crane using straps.

In a preferred embodiment the joists 58 are of typical dimensions for a floor joist, say, again 220mm tall and 45mm wide. The floor 70 may be a layered structure providing a 19mm plank located upon 75mm deep battens 64 and the floor 70 finished with a 22mm thiok decking.

Separating floor 50 also includes an engineered timber ceiling cassette 72. A ceiling cassette 72 is not known to the industry and is first described in Applicants co-pending application GBl0l9659.0. Ceiling cassette 72 can be considered as a reversed floor cassette and is manufactured in a similar manner to that described with reference to Figures 1 and 2.

Ceiling joists 74 are arranged in parallel with recesses 76 now arranged in a base surface 78. Battens 80 are located in the recesses 76 to form a framework with the battens 80 arranged in parallel to each other and orthogonal to the joists 74. The battens 80 each have a width and depth which matches the dimensions of the recess 76. In this way, the cross-section of the batten 80 matches the cross section of the recess 76 and a lower surface 82 of the batten 80 is thus flush with a lower surface 84 of the joist 74. As with the floor cassette 56, fixing the battens 80 in the recesses 76 brings the joists 74 into positive alignment.

The ceiling cassette 72, could be transported to site with the battens 80 bracing the joists 74. Alternatively a panel 86 can be attached to the lower surface 82 of the batten 80 and the lower surface 84 of the joist 74. The panel 86 can form a ceiling which is braced in a first direction by the battens 80 and a second, orthogonal direction, by the joists 74.

In a preferred embodiment, joists 74 are solid timber joists with a rectangular cross-section. Joist 74 has typical dimensions of a ceiling joist, say, 175mm tall and 45mm wide.

The ceiling panel 86 comprises two layers of Gypsum Board, mm 2Okg/m2. The Board has a thickness of 15mm. The ceiling 54 should therefore provide a 60 minute fire rating.

In the preferred embodiment, the joists 58,74 are solid timber which has been treated with a water repellent to reduce shrinkage. They have also been treated with a fire retardant to increase the fire rating of the floor 52 and ceiling 54.

The floor cassette 56 and the ceiling cassette 72 are designed to have the same iength and breadth, so that they stack on top of each other. More importantly, the joists 58,74 are arranged in the same direction with each joist 58,74 lying between two joists 74,58 of the opposite cassette 72,56. Preferably, the joists are symmetrically arranged, so that a joist 58,74 is located in the centre, an equal distance, from the two neighbouring joists 74,58 of the opposite cassette 72,56. In this way, the cassettes 72,56 interleave. This both reduces the height of the separating floor 50 while still providing an isolating air gap between the floor 52 and the ceiling 54. The height of the separating floor 50 is further reduced by recessing the battens 64,80.

In use, the ceiling cassette 72 is lifted onto the construction and located in the desired position. Skilled tradesmen are not required for this as the independent ceiling 54 is pre-assembied. Once in place, the supporting wall is continued to a height at which the floor cassette 56 can now be positioned directly over the ceiling cassette 72. Again skilled tradesmen are not required for this as the structural floor 52 is pre-assembled.

By using a recessed bracing system in both the floor and the ceiling, the construction time can be greatly reduced as pre-assembled cassettes can be brought on site and there is no requirement to remove any temporary bracing before a floor or ceiling can be laid upon the joists.

The principle advantage of the present invention is that it provides a bracing system for construction which does not require to be removed for the installation of floors, ceiling etc. Further advantages of the present invention are that it provides a bracing system which positively aligns the joists, provides permanent restraint and rigidity in the build, speeds up construction time, removes the requirement for skilled tradesmen on site, produces negligible on-site waste, is simple, inexpensive and does not require any additional on site fitting or construction procedures.

It will be appreciated by those skilled in the art that modifications may be made to invention herein described without departing from the scope thereof. For example, the shape of the recess and the battens can be changed as long as they fit' and provide a flush surface when required. In particular the upper edge of the acoustic battens may be shaped to reduce the contact area with the decking located thereon to improve the acoustic isolation. The supported member may comprise individual sheets or planks and need not cover the entire surface area of the joists and battens.

Additionally the number of battens used may be selected by the designer.

Claims (14)

1. CLAIMS1. A bracing system for use in construction, comprising: a plurality of support members arranged in a framework and at least one batten arranged to overlap at least two support members, wherein the support members each have a recess located in a surface thereof and the batten is dimensioned to sit within the recesses.
2. 2. A bracing system according to claim 1 wherein a depth of the recess is equal to a depth of the batten.
3. 3. A bracing system according to claim 1 or claim 2 wherein a width of the recess is approximately equal to a width of the batten. c\Jr
4. 4. A bracing system according to any preceding claim wherein there are a plurality of battens.
5. 5. A bracing system according to any preceding claim wherein the support members are solid timber and the recesses are machined from a first side of the member to a second side of the member.
6. 6. A bracing system according to claim 5 wherein the recess is orthogonal to the support member.
7. 7. A bracing system according to claim 5 wherein the recess is diagonally arranged to the support member.
8. 8. A bracing system according to any preceding claim wherein the support members are joists.
9. 9. A bracing system according to any preceding claim wherein the system further comprises supported components, the supported components being affixed over the framework and recessed battens.
10. 10. A bracing system according to claim 9 wherein the supported components are panel products.
11. 11. A bracing system according to claim 9 or 10 wherein a depth of the recess is less than a depth of the batten.
12. 12. A bracing system according to claim 11 wherein the battens are acoustic battens.
13. 13. A bracing system according to any preceding claim wherein the support members and the battens are treated with a r water repellent.
14. 14. A bracing system according to any preceding claim wherein the support members and the battens are treated with a fire retardant.