GB2508585A

GB2508585A - Building framework element for location within a cavity wall for supporting windows.

Info

Publication number: GB2508585A
Application number: GB201220143A
Authority: GB
Inventors: James Vaux-Anderson
Original assignee: WATES GROUP Ltd
Current assignee: WATES GROUP Ltd
Priority date: 2012-11-08
Filing date: 2012-11-08
Publication date: 2014-06-11
Anticipated expiration: 2032-11-08
Also published as: GB2508585B; GB201220143D0

Abstract

The element 1 comprises a perimeter edge beam 2 formed from rectangular hollow section (RHS) elongate tube and vertical hollow steel wind posts 3 extending from a horizontal top face 4 at intervals along the surface. The RHS may be a square hollow section and the vertical members may be welded on. The vertical members may be narrower than the horizontal portions they are mounted on but the external faces of a vertical portion may still be flush with the external face 5 of the RHS. Also claimed is a method of constructing a building with the building element. The element may be located within a masonry cavity wall. A floor slab of the building may extend into the cavity so that a concrete infill of the floor abuts the internal faces of the wind posts and around the wind posts. The method may use variable thickness, width blocks which accommodate the wind posts and allow a uniformly flush wall surface.

Description

Building Element The present invention relates to a building element, particularly but not exclusively, to a building element for a steel framed building having ribbon windows, and to a method of constructing such a building.

Traditionally, steel-framed buildings with ribbon windows (i.e. windows that are provided in a continuous horizontal strip consisting of two or more framed windows), require bespoke structural support to be provided for the window, dependent on the particular size, shape and position of the window. Consequently, the structural support must be designed specifically for each window, thereby limiting the scope of changes to window design after the structure is in position.

Furthermore, steel-framed buildings also required support to be provided for the non-window façade of the building, for example masonry or other building panels, to be supported on the building structure. Often this requires some sort of shelf angle to be mounted to the building structure for the external skin, for example a masonry cavity wall, to be mounted thereto.

One traditional method of providing a building element for a steel-framed building is to provide a perimeter edge beam, for example an I-beam or Rectangular Hollow Section (RHS) beam to support an edge of a floor /roof slab. The floor/roof slab is supported by a top face of the edge beam and other support structural members, for example for supporting façade panels, are attached to the beam, often to a vertical face of the edge beam. Generally, with this type of construction, a separate horizontal member is also required, typically spanning between vertical main columns of the structure, to provide support for the windows. As mentioned, these separate horizontal members, and any other structural elements needed to support the windows, therefore need to be specially designed and installed to meet the required specific window locations and sizes.

A building element that minimises the amount of bespoke design and installation, and can standardise the frame design would therefore be desirable in order to provide economies in both production and erection.

Aspects and examples of the invention are set out in the claims and address at least a pad of the above described problem.

In some embodiments, the invention may provide a building element comprising a perimeter edge beam formed of a steel Rectangular Hollow Section (RHS), fabricated with vertical hollow steel wind-posts extending from a horizontal top face thereof at intervals therealong. The element is arranged to be positioned at least partly within a cavity of an external wall of a building, such that an external façade of the building can be laterally constrained by the vertical wind-posts.

In some embodiments, the invention may provide a method of constructing a building by providing a building element comprising a perimeter edge beam formed of a steel Rectangular Hollow Section (RHS), having a plurality of vertical hollow steel wind-posts extending from a horizontal top face thereof at intervals therealong. A floor slab is arranged to be supported by the horizontal top face of the RHS, and a masonry cavity wall is preferably constructed around the building element, such that the wind-posts are arranged wholly or partly within a cavity of the cavity wall.

Windows of the building may be arranged to be supported between the top of the masonry wall, which transposes the load to the wind-posts via, for example, brick ties, and the bottom face of the next storey RHS, so that no further steel support members are required. The floor slab of the building supported on the horizontal top face of the RHS may extend so that concrete infill of the floor slab abuts an internal face of the wind-posts and extends around side faces of the wind-posts.

The steel wind-posts are preferably square hollow sections and may be attached, for example by welding, to the RHS during fabrication. The wind-posts are preferably of smaller cross-sectional extent than the horizontal top face of the RHS and are attached to the RHS at regular intervals. Preferably, external faces of the wind-posts and the RHS are arranged to be substantially flush. Inner blocks of the cavity wall may be arranged to be of full thickness between the wind-posts, but thinner where the wind-posts are located wholly within the cavity, so that internal faces of the inner blocks are flush both between the wind-post locations and at the wind-post locations. Preferably, the building element is installed to an entire perimeter of the building and may be continuous therealong.

It will be appreciated that structural aspects may be applied to method aspects and vice versa. The skilled reader will appreciate that structural embodiments may be adapted to implement features of method embodiments and that one or more features of any of the embodiments described herein, whether defined in the body of the description or in the claims, may be independently combined with any of the other embodiments described herein.

An embodiment of the invention will now be described in greater detail, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a schematic perspective view of a building element according to one embodiment of the invention; Figure 2 shows a vertical cross-sectional view through a building constructed in accordance with one embodiment of the invention taken through a blockwork cavity wall of the building incorporating the building element of Figure 1; Figure 3 shows a vertical cross-sectional view through the building of Figure 2, but taken through a wind-post portion of the cavity wall of the building; Figure 4 shows an enlarged view of a portion of Figure 2; Figure 5 shows a horizontal cross-sectional view taken along line V-V in Figure 3; and Figure 6 shows a horizontal cross-sectional view taken along line VI-VI in Figure 3.

Referring, firstly, to Figure 1, a building element 1 is formed of an RHS steel beam 2 fabricated with a plurality of square hollow section members 3 arranged perpendicularly to the RHS beam 1 at intervals to provide wind-posts. The RHS beam 2 may be, for example, 300mm high x 200mm wide x 8mm thick, but any appropriate size, for example in the range 100 to 500 mm high x 50 to 300mm wide x 4 to 10 mm thick, may be used, depending on the circumstances. The square hollow section members 3 are preferably 80mm x 80mm x 4mm (thick), but, again, any appropriate size, for example 50 to 100mm x 3to 10 mm (thick), may be used depending on the circumstances. The wind-posts 3 are attached to a top face 4 of the RHS beam 2 so as to be flush with a side face 5 of the RHS beam 2, and are preferably welded to the RHS beam 2, but can be otherwise attached thereto, as desired.

Turning now to the remainder of the drawings, in which the same elements are referred to with the same reference numbers, as best seen in Figure 3, the building element of Figure 1 is incorporated into a hollow external wall 6 of a building. It is noted that Figure 3 is a cross-sectional view through the external wall 6 at a location through a wind-post 3, whereas Figure 2 is a similar cross-sectional view through the external wall 6 at a location between two wind-posts. The wall 6 is formed by an outer wall 7 formed of outer masonry 9, preferably of 100mm thickness, and an inner wall 8 formed of inner fair-faced blocks 10, preferably of 140mm thickness in the areas between the wind-posts 3 and of 75mm thickness in the areas adjacent the wind-posts 3. The masonry may be blockwork, brickwork, stonework or other appropriate material. The cavity 11 between the outer and inner walls 7 and 8 is preferably about 150mm wide and is filled, or partly filled, with insulation 12. A render 13 may be provided on the external face of outer wall 7, if desired. Since a space extends around each wind-post 3 by the difference in thickness between the 140 mm and 75mm inner blocks 10 for a length of one inner block, the courses of blocks (of which one is shown in Figure 5), are staggered so that the space is arranged on one side of the wind post 3 in one course and on the other side of the wind-post 3 in the next adjacent course of blocks.

The RHS beam 2 may be arranged such that concrete 15 of a floor member 14 is infilled to pre-cast planks 16 so as to abut and extend around the wind-posts 3.

The RHS beam 2 is cantilevered to encroach into the cavity 11 of the wall 6, preferably by about 60mm. The infill concrete 15 is thus supported on the top face 4 of the RHS beam 2 both between and abutting against the wind-posts 3. A masonry support system 16 for supporting the outer blocks 9 is mounted to an outer side face of the RHS beam 2. The masonry support system 16 includes support brackets 18, which are mounted to the RHS beam 2 using bolts 19 through slotted holes in the support brackets 18 to provide adjustment capability and a continuous masonry support angle 20, mounted to the support brackets 18 for supporting the outer blocks 9.

The wind-posts 3 can be designed and installed or modified on-site to any desired height according to the size and shape of the windows 21. Alternatively, they may be attached to the RHS off-site. The inner and outer walls 7 and 8 are built to the same height and the cavity 11 is closed off cavity closers 22. The windows 21 are generally pre-formed double glazed systems with powder coated aluminium frames 23, which are mounted to the top of the wall 6, supported by the tops of the wind-posts 3. A window head strap 17 extends from the tops of the window frames 23 and is fixed to the underside of the RHS beam 2.

As mentioned above, the wind-posts 3 are fabricated with the RHS beam 2 to be flush with an external face of the RHS beam 2. Since the RHS beam 2 extends into the cavity 11, the wind-posts 3 extend by no more than 60mm into the cavity 11.

The RHS beam 2 is usually joined with similar RHS beams 2 to form one continuous beam 2 around the perimeter of the building. Since the wind-posts 3 are already fabricated on the beam 2 at regular intervals, the windows can be easily positioned, as required. Furthermore, each storey, including the roof can be formed in the same way using the same building structural element 1. The same arrangement can also be used at the roof level, with the spacing of wind-posts dependent on the height of the parapet.

It will therefore be seen that the building structure described above provides a standardised and cost-effective solution that can be applied to the entire façade of the building (leading to economies of scale, simplification of individual building design and repetition of design from building to building), allows for flexibility in the size and placement of windows during initial construction (reducing costs in structural design, labour and materials to change frame if the architectural design changes), that provides a structure suitable for varying façade treatments without the requirement for extensive re-design (which in turn makes it suitable for changes in façade treatment through the building life), and that therefore simplifies construction and air-tightness detailing. This system can be installed to the entire perimeter of the building, which standardises the frame design throughout the building (and across multiple buildings/sites) leading to economies in production and erection. Because the RHS steel edge-beam is a shallower section (height), the windows can be installed closer to soffit/ceiling, which leads to more daylight in the building.

It will further be appreciated that although only one particular embodiment of the invention has been described in detail, various modifications and improvements can be made by a person skilled in the art without departing from the scope of the present invention.

Claims

Claims 1. A building element comprising a perimeter edge beam formed of a steel Rectangular Hollow Section (RHS), fabricated with vertical hollow steel wind-posts extending from a horizontal top face thereof at intervals there along.
2. A building element according to claim 1, which is positioned at least partly within a cavity of an external wall of a building, such that an external façade of the building can be laterally constrained by the vertical wind-posts.
3. A building element according to either claim 1 or claim 2, wherein the perimeter edge beam extends around the perimeter of a building.
4. A building element according to any preceding claim, wherein the wind-posts are square hollow sections.
5. A building element according to any preceding claim, wherein the wind-posts are attached to the RHS beam during fabrication off-site.
6. A building element according to any preceding claim, wherein the wind-posts are attached to the RHS beam during fabrication on-site.
7. A building element according to either claim 5 or claim 6, wherein the wind-posts are attached to the RHS beam by welding.
8. A building element according to any preceding claim, wherein the wind-posts are of smaller cross-sectional extent than the horizontal top face of the RHS beam.
9. A building element according to any preceding claim, wherein the wind-posts are attached to the RHS beam at regular intervals.
10. A building element according to any preceding claim, wherein external faces of the wind-posts and the RHS beam are arranged to be substantially flush.
11. A method of constructing a building by providing a building element according to any preceding claim within a building.
12. A method of constructing a building according to claim 11, further comprising constructing a masonry cavity wall around the building element, such that the wind-posts are arranged at least partly within a cavity of the cavity wall.
13. A method of constructing a building according to claim 12, wherein a floor slab of the building extends into the cavity so that concrete infill of the floor slab abuts an internal face of the wind-posts and extends around side faces of the wind-posts.
14. A method of constructing a building according to claim 13, wherein the floor slab is arranged to be at least partly supported by the horizontal top face of the RHS beam.
15. A method of constructing a building according to any one of claims 11 to 14, further comprising arranging inner blocks of the cavity wall to be of full thickness between the wind-posts, but of reduced thickness adjacent the wind-posts, so that internal faces of the inner blocks are flush both between the wind-post locations and at the wind-post locations.
16. A method of constructing a building according to any one of claims 10 to 15, wherein the building element is installed to an entire perimeter of the building.
17. A method of constructing a building according to any one of claims 10 to 16, further comprising arranging windows of the building to be supported between a top of the masonry cavity wall and the bottom face of a next storey RHS.
18. A building structure substantially as hereinbefore described with reference to the drawings.
19. A method of constructing a building substantially as hereinbefore described with reference to the drawings.