GB2490304A

GB2490304A - Structural beam with insulation located in a cavity within the beam.

Info

Publication number: GB2490304A
Application number: GB201104673A
Authority: GB
Inventors: Ian De Haan
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-03-18
Filing date: 2011-03-18
Publication date: 2012-10-31
Anticipated expiration: 2031-03-18
Also published as: GB201104673D0; GB2490304B

Abstract

The beam 10 has a cross-sectional width to depth ratio in the range 0.25 to 4, or one side is no more than four times greater than the other. The beam is formed from four layers 11, 12, 13, 14 and at least one web 15 located within the beam to define at least two insulation spaces 18, preferably comprising insulation, within the beam. Also claimed are a panel with a number of beams, each with a cross sectional width to depth ratio in the range 0.25 to 4 and include at least one insulation void, arranged parallel to each other and including a facing board on top of the beams. Also claimed is a wall made with at least two beams similar to those in the panel. Also claimed is a floor with beams parallel to each other and each including an insulation space. Also claimed is a structure with the beams, panel, walls and floor as claimed and a method of constructing said structures with beams.

Description

A

Structural Beams And Methods Of Formin Structure The present invention relates to structural beams for use in the construction of temporary and permanent structures. In particular, the present invention relates to structural beams for the construction of wooden structures, It is known to construct temporary and permanent structures from pre-fabricated wall, floor and roof sections. Structural insulated panels (SIPs) are often used for this purpose. SIPs typically comprise two facing layers of orientated strand board (OSB) which are adhered together by an insulating core of pressure injected polyurethane foam and are well known in the construction industry. These panels have a number of benefits including relatively low production costs and good strength and insulation properties. However, these advantages can be diminished when openings for doors and windows are included as any such openings must be reinforced by a timber frame and/or lintel in order to maintain the overall strength and integrity of the panel. This can add considerably to build times or, if the openings are pre-cut into the panels during manufacture, to the cost of the panels.

Structural panels having multiple layers of OSE separated by layers of rigid foam insulation are also known.

Such panels are constructed by gluing the various layers together in a sandwich-like configuration. However, these panels are susceptible to de-larnination under load and therefore have limited application. p

Alternative structural panel designs have been proposed such as that described in GB 2 415 714 and the applicant's own GB 2 450 359. These panels variously comprise layers of structural board, insulation and stiffening. In each case the structural panels are fabricated off site to the specific requirement of a structure and transported to site before being erected. Where openings for doors and windows are required, these are provided in the panels during fabrication adding to build times and the eventual cost of the panels.

In a first aspect, the present invention provides a structural beam having a cross-sectional width to depth ratio in the range 0.25 to 4, the beam comprising: first and second face layers; first and second edge layers; and at least one web, wherein the at least one web is located within the beam and arranged such that it is substantially parallel to and spaced from either the first and second face layers, or the first and second edge layers, to define at least two insulation spaces within the beam.

The structural beams of the present invention are advantageous as they provide standardised sub units from which larger structures or assemblies may be constructed.

They may be used in various ways to form different load bearing sections of a structure thus providing enhanced flexibility of use and reducing fabrication costs.

In a preferred example, the beam has a cross-sectional width to depth ratio in the range 0.33 (one third) to 3, and in a further preferred example, the beam has a cross-sectional width to depth ratio in the range 0.5 to 2.

Insulation material is preferably located in at least one of the insulation spaces to improve the insulation properties of the beam.

Preferably, stiffening ribs are provided to stiffen the beam. The stiffening ribs are at least partially located within each end of each insulation space and substantially close the ends of the insulation spaces.

In a preferred embodiment, the first and second edge layers comprise engagement features to facilitate engagement with adjacent structural beams in use. The engagement features preferably comprise at least one groove in the exterior surface of each of the first and second edge layers.

The present invention further provides a structural panel comprising a plurality of structural beams, each beam having a cross-sectional width to depth ratio in the range 0.25 to 4 and comprising; first and second face layers; first and second edge layers; and at least one insulation space, the beams being arranged side by side such that the edge layers of adjacent beams are substantially parallel and face one another, the panel further comprising at least one panel facing board located over the face layers of at least two adjacent beams.

The panel of the present invention is advantageous as it provides a versatile structural sub-unit which may be used to fabricate all major components of a structure. In particular, floors and roofs.

In a preferred example, the beams have a cross-sectional width to depth ratio in the range 0.33 (one third) to 3, and in a further preferred example, the beams have a cross-sectional width to depth ratio in the range 0.5 to 2.

Preferably, the at least one panel facing board partially overlaps a first beam and partially overhangs a second beam to provide a convenient means of interlocking adjacent panels.

The adjacent beams of the panel are preferably engaged with one another via engagement features located on the exterior surfaces of the edge layers. Preferably, the engagement features comprise at'least one groove in the exterior surface of each of the edge layers, the panel further comprising rails located within the grooves.

In a preferred embodiment, the beams are longitudinally offset with respect to one another to provide further interlocking between adjacent panels.

The beams of the panels preferably comprise beams according to the first aspect of the present invention.

The present invention also provides a floor, a roof or a wall comprising a plurality of the structural panels arranged in an array.

In a further aspect, the present invention provides a wall comprising a plurality of structural beams, each beam having a cross-sectional width to depth ratio in the range 0.25 to 4 and comprising: first and second face layers; first and second edge layers; and at least one insulation space, wherein the beams are arranged side by side such that the edge layers of adjacent structural beams are substantially parallel and face one another. This wall structure is advantageous as openings for doors and windows may readily be provided by adapting the length of the beams in the wall.

The wall preferably further comprises a coping beam to stabilise the wall arid spread the load of overlying structures. The coping beam is located at the top of the plurality of beams and supported by at least two of the plurality of beams.

Preferably, one or more of the structural beams or coping beam of the wall comprise beams in accordance with the first aspect of the present invention.

In another aspect, the present invention provides a floor, a ceiling or a roof comprising a plurality of structural beams arranged in an array, each beam having a cross-sectional width to depth ratio in the range 0.25 to 4 and comprising: first and second face layers; first and second edge layers; and at least one insulation space, wherein the beams are arranged such that the edge layers of adjacent structural beams are substantially parallel and face one another.

In one preferred embodiment the array forming the floor, ceiling or roof comprises a plurality of beams arranged end to end to extend the span of the floor, ceiling or roof.

The structural beams of the floor, ceiling or roof preferably comprise beams in accordance with the first aspect of the present invention.

The present invention also relates to a structure comprising a plurality of structural beams according to the first aspect of the present invention and/or a plurality of structural panels, walls, floors, ceilings or roofs as described above.

The invention also relates to a method of forming at least part of a structure comprising arranging a plurality of structural beams according to the first aspect of the present invention in an array.

Similarly, the present invention relates to a method of forming at least part of a structure comprising placing a plurality of the structural panels in an array.

Further, the present invention relates to a method of forming at least part of a structure comprising forming a wall, a floor, a ceiling or a roof as described above.

Examples of the invention will now be described in greater detail with reference to the following drawings in which: Figure 1 shows a partially exploded view of part of a wall and a panel comprising beams according to the present invention; Figure 2 shows a further partially exploded schematic view of Figure 1; Figure 3 shows a schematic view of a panel according to the present invention; Figures 4A and 4B show possible panel arrangements in a floor or roof array; Figure 5 shows an array of panels comprising surface dowels; Figure 6 shows a view of a partial structure comprising a wall and panels comprising beams according to the present invent ion; Figure 7 shows a wall comprising surface dowels; Figure 8 shows a partially exploded view of a further structure; Figure 9 shows an alternative partially exploded view of the structure of Figure 8; Figure 10 shows a schematic view of a party wall arrangement; Figure 11 shows a schematic view of an alternative party wall arrangement; Figure 12 shows a floor comprising a plurality of beams with connecting dowels; Figure 13 shows an exploded beam suitable for use in the floor of Figure 12; Figure 14 shows a skeleton view of a floor comprising a plurality of beams; Figures iSA to lSC show a door or window frame arrangement; Figures 16A and 168 show beams with additional surface sealing grooves; Figure 17 shows a beam having an alternative configuration of internal webs and additional insulation; Figure 18 shows a panel comprising additional insulation; Figure 19 shows a stiffening insert; Figures 20A and 208 show a steel-T for use with the beams; Figure 21 shows a further alternative structure comprising beam posts and hung walls; and Figures 22A and 223 show part of an example demountable structure.

The basic sub-units of the structures to be described below are structural beams. Example structural beams 10 are shown and described in relation to Figures 1 to 3 and 4.

The structural beams 10 comprise first 11 and second 12 face layers and first 13 and second 14 edge layers. As best shown in Figure 3, the edge layers 13, 14 are connected to the face layers 11, 12 by rebate joints with the rebate cut into the inner surfaces of the edge layers 13, 14. The joints are glued for structural integrity and may also be fixed by mechanical fixings such as stainless steel screws.

The joints between the edge layers 13, 14 and face layers 11, 12 may also be made the other way around such that the rebate is in the face layers 11, 12. Any other type of suitable joint may also be used.

The beams 10 further comprise webs 15 located in spaced relationship to the face layers 11, 12. The webs 15 are substantially parallel to the face layers 11, 12 and define a number of insulation spaces 18 within the beams 10. The webs 15 are jointed to the inner surfaces of the edge layers 13, 14 by housing joints as shown in Figure 3. The joints are glued for structural integrity and may also be fixed by mechanical fixings such as stainless steel screws. Any other type of suitable joint may also be used.

The beams 10 further comprise grooves 16 located on the outer surface of the edge layers 13, 14. The grooves 16 facilitate engagement of adjacent beams 10 in the assembled structures (described in greater detail below). The Figures show two parallel grooves 16 running the length of the beams 10. Alternatively only one groove 16 may be used, or three or more grooves 16 may be used.

Blocks of insulation material 17 are located in the insulation spaces 18. The insulation material is sized to fit within the insulation spaces 18. The insulation material may comprise any suitable material such as polystyrene or wood fibre. The insulation 17 may be selected to have certain beneficial properties such as fire resistance or sound deadening. In one example, the two insulation spaces 18 proximate the face layers 11, 12 may contain a sound deadening material, while the middle insulation space 18 between the webs 15 contains a fire resistant material. Any configuration of insulation material as desired may be used. Insulation material 17 may be located in all of the insulation spaces 18, or only in some of the insulation spaces 18. Alternatively or -10 -additionally, different types of insulation material 17 may be located in different insulation spaces 18. The insulation material 17 may be glued in place if desired.

The open ends of the insulation spaces 18 are closed by stiffening ribs 19. The stiffening ribs 19 seat in the end of the insulation spaces 18 and provide lateral and torsional stiffening. The stiffening ribs 19 are glued and/or screwed in place and may comprise engineered wood. or any other suitable material. Alternatively, the stiffening ribs 19 may comprise a sandwich of orientated strand board (OSE) layers which have been glued and/or screwed together.

Example stiffening ribs of this type are indicated by reference numeral 1618 in Figure 14.

The face layers 11, 12, edge layers 13, 14, webs 15, and optionally stiffening ribs 19 comprise OSE. However, some or all of these components may comprise any other suitable material such as magnesium oxide board.

In one example, the beam 10 has a length of 3m, a face width (defined as the perpendicular distance between the outer surfaces of the edge layers 13, 14) of 400mm, an edge width (defined as the perpendicular distance between the outer surfaces of the face layers Il, 12) of 300mm. These dimensions correspond to a cross-sectional width to depth ratio of 1.33 (or 4/3), where the face width corresponds to the beam's cross-sectional width, and the edge width corresponds to the beam's cross-sectional depth. The 053 has a thickness of 20mm. The inventor has found these dimensions to be suitable for the construction of buildings.

-1]. -However, any other dimensions may be selected in accordance with design requirements.

In an alternative embodiment, described in greater detail below, the webs 15 may be orientated such that they are substantially parallel to the edge layers 13, 14.

The beams 10 may be arranged to form structural panels.

An example structural panel 100 is shown in Figure 3. The structural panel 100 comprises three beams 10 arranged side by side so that the edge layers 13, 14 of adjacent beams 10 are substantially parallel and face one another. The grooves 16 of adjacent beams 10 lie in registration with each other and rails 20 fit within the grooves 16 to provide engagement and location between the beams 10. The rails 20 may comprise any suitable material such as engineered wood, steel or OSS. The rails 20 are glued and/or screwed in place. In the example shown, the rails 20 are 10mm wide and 15mm high.

The panel 100 further comprises panel facing boards 101 located on either side of the beams 10. The panel facing boards 101 overlie the face layers 11, 12 of the beams 10 such that on one side of the panel they overhang the underlying beam 10, and on the other side of the panel they only partially overlap the underlying beam 10. The panel facing boards 101 comprise 20mm thick OSE and are glued and/or screwed to the underlying beams 10. As discussed in greater detail below (Figure 18), insulation material may be placed between each of the beams 10 in the panel and/or between the beams 10 and panel facing boards 101. In an -12 -alternative example (not shown) the panel 100 may comprise only one panel facing board 101.

As with all beams and structures described herein, the S various componedts of the beams 10 and panels 100 are preferably glued together in a vacuum environment. Although the gluing together in a vacuum environment is preferred, it is not essential.

The structural panels 100 may be used in the construction of any part of a building. However, they are particularly suitable for the construction floors or roofs by arranging a plurality of the panels 100 in an array. In such an array, panels 100 are placed side by side such that the overhanging sections of panel facing board 101 on one panel overlap the uncovered section of beam 10 on an adjacent panel 100. The panels 100 may be placed end to end to extend the floor/roof in two dimensions. An example size for the structural panels 100 is 2.5m by l.25m.

The stiffening ribs 19 may be used to connect the ends of beams 10 in adjacent panels 100 together. This can be achieved by omitting the stiffening ribs 19 from some or all of the insulation spaces 18 at one end of the panels 100 and providing elongated stiffening ribs, which protrude from the insulation spaces, at the other end of the panels 100. When the panels 100 are joined end to end in an array, the elongate stiffening ribs of one panel 100 engage with the insulation spaces 18 of an adjacent panel to form a connection. The insulation 17 within the insulation spaces 18 is sized accordingly. The elongate stiffening ribs -13 -provide connection between adjacent beams and improve the bending stiffness of the array, The beams 10 of the panels 100 may also comprise doweled connections which are described in greater detail below with respect to Figures 12 and 14.

It is not necessary that the panels 100 be arranged such that the end to end abutment of one panel 100 is in exact registration with an adjacent panel 100. Figure 4a illustrates an array of panels 100 in which the end to end abutment between panels is in exact registration and Figure 4b illustrates an array in which the end to end abutment is offset such that the ends of the beams 10 in one panel abut or connect to beams in more than one adjacent panel.

A floor or roof may comprise only the panels 100.

Alternatively, the top and/or bottom of the array may be covered by a further layer of OSB boards or any other suitable material. If desired further insulating material may be placed between the outer surfaces of the panel facing boards 101 and the overlying boards. The overlying boards are preferably not in registration with the panel facing boards 101 in order to provide greater stability and rigidity to the final structure. Any conventional floor or roof covering may be applied to the panels 100 or additional covering boards. Any number of layers of additional boards/insulation may be used as desired.

Figure 5 shows an example of a section of floor made up from a plurality of panels 100. In this example the top and bottom of the panels 100 are covered by additional OSE -14 -boards 103 which are fixed to the underlying panel facing boards 101 by glue and/or screws. A plurality of dowels 102 are positioned in pre-drilled holes 104 which extend through the outer covering of OSB boards 103, the panel facing boards 101 and the face layers 11, 12 of the beams 10. The dowels are glued and/or screwed in place. In this example, the OSB boards forming the face layers 11, 12, the panel facing boards 101 and covering boards 103 are 15mm thick.

The dowels 102 are 45mm long, in order to extend through all three layers, and 40mm in diameter. If any additional layers of insulation are placed between the panel facing boards 101 and the beams 10, or the covering boards 103 and the panel facing boards 101, the length of the dowels 102 is increased accordingly.

The dowels 102 arrest movement and deflection in the structure and help to keep the panel facing boards 101 and covering boards 103 rigid and joined to the beams 10. This, in turn, helps the structure to span greater distances or take greater loads.

Figure 5 illustrates that a floor may be made up of a plurality of complete panels 100 and any number of partial panels as required to fit the desired dimensions.

similarly, the panel facing boards 101 and covering boards 103 may be whole or cut to size as necessary. The partial panels may be pre-fabricated or cut to size on site.

Structural panels 100 may be used to form the walls of a structure. However, it is preferred that the walls of a structure be formed from individual beams before being faced with OSB panels, SIPs or similar.

-15 -A section of wall 200 is shown in Figures 1. and 2. The wall 200 comprises four beams 10 identified as A, B, C, ID.

The beams 10 are placed in a substantially vertical orientation side by side so that the edge layers 13, 14 of adjacent beams 10 face each other and are substantially parallel. As with the panel 100 described above, the grooves 16 of adjacent beams 10 lie in registration with each other and rails 20 fit within the grooves 16 to provide engagement between the beams 10.

In order to provide a window space, beams B and C are shorter than the adjacent beams A and P. The top of the beams B and C forming the window space is covered by an OSS window board 201. Space for a door may be provided by omitting beams from the wall array or by providing short sections of beam or other material to form a step.

The top of the wall 200 comprises a coping beam 300 which in this example comprises a beam 10 as described above. In the example shown, the coping beam 300 also forms a lintel over the window space. If it is desired to form a smaller window space, a second horizontal section of beam (not shown) or other material can be used to fill in the top of the window space. In this example, the coping beam 300 is orientated such that the edge layers 13, 14 of the beam are on the horizontal plane. If desired, the coping beam 300 may be orientated such that the face layers 11, 12 are in the horizontal plane.

The wall 200 is faced on either side with 20mm thick OSB panel facing boards 202 cut to size in the factory or on site. If desired, additional layers of insulation may be -16 -used between the beams 10 and the panel facing boards 202.

The panel facing boards may themselves comprise SIPs having an outer layer of OSB glued to an underlying layer of polystyrene or urethane sheets. Furthermore, if desired, S the facing layers of OSB (or other material) may be sized to leave a gap around the edge of the wall, which gap may be filled with insulating material to provide additional heat and/or sound insulation.

Figure 6 shows part of a structure comprising panels and a wall 200, each comprising beams 10. The structure comprises a lower floor 110 comprising an array of structural panels 100 (only one panel shown). A wall 200 rests on top of a load board 400 which comprises 40mm thick 058. The load board 400 helps to spread the load of the wall over the floor 110. Grooves (not shown) may be provided on the lower surface of the load board 400 for engagement with crane webbing. Although a load board 400 is desirable, it is not essential.

A second floor 120 comprising a second array of structural panels 100 (only one panel shown) rests on the coping beam 300. A second load board 401 is provided on top of the floor 120 to help spread the load of any wall built on top of it.

Figure 7 shows an example wall 210 comprising beams 211, a coping beam 310 and facing boards 212. The beams 211 and coping beam 310 are substantially as described above for beams 10. In this example, the wall comprises a plurality of dowels 205 positioned in pre-drilled holes 204 which extend through the facing boards 212 and the face layers of -17 -the beams 211. The dowels 205 are glued and/or screwed in place. In this example, the OSE boards forming the face layers of the beams 211 and facing boards 212 are 15mm thick. The dowels 205 are 30mm long, in order to extend through both layers, and 40mm in diameter. If any additional layers of insulation are placed between the facing boards 212 and the beams 211 the length of the dowels 205 is increased accordingly.

Dowels 102, 205 such as those shown in Figures 5 and 7 may be used in any of the structures described herein. As mentioned above with respect to Figure 5, the dowels help to increase resistance to deflection and increase load capacity. In cases where the wall structures comprise dowels 205 such as those shown in Figure 7, load boards 400, 401 (see Figure 6) may be omitted. As described in greater detail below, dowels may also be used to connect the walls to the underlying structures.

Figure 8 shows a partially exploded schematic view of another structure 500 comprising beams 10. Where like elements are shown, the same reference numerals as used above have been used for clarity.

The structure 500 comprises walls 200 constructed as described above with reference to Figures 1, 2 and 4. In this example the panel facing boards 202 are arranged to cover the vertical beams 10 and the horizontal coping beam 300 of the wall 200. This helps to add stability and strength to the wall structure.

-18 -The walls 200 rest on load boards 402, 403 which comprise a plurality of apertures 405 for receiving wooden or steel dowels 406. The dowels 406 join and locate the various sections of the structure 500.

The structure 500 comprises two floors 600, 601. The floors 600, 601 are made up of an array of structural panels 700 which comprise three beams 10 arranged side by side so that the edge layers 13, 14 of adjacent beams 10 face each other and are substantially parallel. Unlike the arrangement of beams in structural panel 100 described above, the beams 10 of structural panels 700 are longitudinally offset from one another. As before, panel facing boards 701 are located on either side of the beams 10. The panel facing boards 701 overhang one end and one side of the array of beams 10. When the structural panels 700 are arranged together in an array to form the floors 600, 601, the protruding beams 10 of the panels interlock with the spaces of adjacent panels to form an interlocked array. The floors 600, 601 are finished with facing layers of OSB boards 800, 801. The panels 700 at the edge of the floors 600, 601 may include shorter sections of beam 10 to fill the spaces in the panels 700 at the edge of the floor.

The floors 600, 601 comprise apertures 407 at their outer edges for receiving the dowels 406 and the coping beam 300 comprises apertures 408 for receiving the dowels 406.

The dowels 406 connect the walls of the structure 500 to the underlying and overlying floors 600, 601.

Figure 9 shows an alternative view of the structure 500 of Figure 8. Figure 9 additionally illustrates a roof -19 -structure 900 which comprises an array of structural panels 700 arranged as described above with respect to floors 600, 601. The structural panels 700 forming the roof 900 are finished with facing layers of OSE boards 901.

The roof 900 is supported on the upper ends 950 of beams 10 forming the side wall 960 of the structure 500.

the upper ends 950 of the beams 10 have been cut to form a pitched angle which defines the pitch of the roof 900. The upper ends 950 of the beams 10 are covered by beam end facing boards 955 which comprise apertures 409 for receiving wooden or steel dowels 406. The roof 900 is located and attached to the upper ends 950 of the beams 10 by the dowels 406 which engage in the apertures 409 and corresponding apertures (not shown) in the roof 900. Beam end facing boards 955 may also be placed on the top and bottom of beams comprising walls 200, 960.

Figure 9 also shows base boards 410 upon which the floor 600 rests. The base boards 410 rest on stainless steel plates which in turn rest on a concrete base. The base boards 410 comprise apertures 411 for engagement with wooden or steel dowels 406 which in turn locate with and fix to apertures in the floor 600. The entire structure 500 may rest on concrete, or other suitable material, pile foundations (not shown).

Figure 10 shows a party wall arrangement such as may be used between rooms in a building or to separate dwellings in flats or semi-detached houses or the like. The party wall 1000 comprises a plurality of vertical beams 1010 arranged side by side with a coping beam 1300 resting on the top of -20 -the beams 1010. The beams 1010 are similar to the beams 10 described above but comprise no webs 15 such that there is only one insulation space. In this example the beams 1010 have a width of 400mm and a depth of 100mm. This corresponds to a cross-sectional width to depth ratio of 4.

The coping beam 1300 has the same basic structure as the beams 1010. The party wall further comprises panel facing boards 1202 which cover the vertical beams 1010 and the coping beam 1300. The party wall 1000 rests on load board 1400.

Figure 11 shows an alternative arrangement for a party wall 1500. The party wall 1500 comprises two of the party walls 1000 arranged with a gap 1501 between them. The gap helps to prevent noise transmission through the party wall 1500.. The gap 1501 may itself contain insulation, sound deadening material or fire-proof material.

In the embodiments described above, the floors and roofs have been made up from a plurality of thaneis 100, 700 arranged in an array. In an alternative example, floors or roofs may be constructed by forming an array of beams which are then covered by one or more layers of facing boards.

A suitable arrangement for a floor or roof is shown in Figure 12. Figure 12 shows a section of floor 1600 part way through construction. The floor 1600 comprises a plurality of beams 1610 having generally the same constructions as beams 10 described above. The beams 1610 are arranged in an array side by side such that the edge layers 1613, 1614 are substantially parallel and face one another. The beams 1610 are glued and/or screwed together. The floor 1600 also -21 -comprises rails 1620 located in grooves 1616 on the outer surfaces of the edge layers 1613, 1614.

Each beam 1610 comprises a plurality of dowel holes 1602 which are sized to receive dowels 1601. The dowels 1601 are solid wooden dowels having a socket 1606 at one end and a plug 1607 at the other end. Any other suitable material, such as steel or aluminium tubing, may be used f or the dowels 1601. In use, the dowels are placed in a linked chain 1608 through the dowel holes 1602 to help join the beams 1610 in the floor 1600 and provide additional strength and rigidity to the structure. The dowels 1601 are placed so that the joins between adjacent dowels in the chain 1608 are positioned substantially at the midpoint of the beams 1610. The dowels are glued and or screwed together. At the outer edges of the completed floors, half length dowels are used.

An example beam 1610 for use in a floor 1600 is shown in Figure 13. Figure 13 illustrates that the insulation 1617 has holes 1603 which lie in registration with the dowel holes 1602 so that the dowels 1601 may pass through. Figure 13 also illustrates that the insulation 1617 is shorter in length than the beam 1610 so that elongate stiffening ribs 1619 may be placed in the ends of the insulation spaces 1618 to facilitate end to end connection of the beams 1610.

In this example, the elongate stiffening ribs 1619 comprise two holes 1605 to receive the dowels 1601. The stiffening ribs 1619 comprise four layers 1621 of OSB glued and/or screwed together.

-22 -Figure 14 shows a skeletal view of a floor 1600 comprising beams 1610 arranged as described above. The face layers of the beams and the insulation are not shown to clarify the internal connections within the floor 1600.

As shown, a chain 1608 of dowels 1601 pass through each of the dowel holes 1602 across the entire width of the floor 1600. End to end connections between beams are made via the elongated stiffening ribs 1619. At each end to end beam connection extra dowels 1604 are optionally provided to enhance the strength of the connection. The stiffening ribs 1618 at the ends of the floor are flush with the ends of the beams 1610.

The completed floor is faced with layers of OSE, or any other suitable material, which is glued and/or screwed to the underlying face layers of the beams 1610. Insulation may be placed between the face layers of the beams and the overlying boards. Any number of boarding layers/insulation layers may be used. In addition, the facing boards, insulation and face layers of the beams my be connected by dowels 104 such as those shown and described with reference to Figure 5.

The dowel connections described above with reference to the floor 1600 can be also be used in any of the above panel, floor, roof or wall structures. As many or as few dowels as desired may be used and there is no requirement that dowels pass through all insulation spaces in any given beam or structure. One advantage of using wooden dowels, or other poor heat-conducting materials, is that it avoids problems of cold bridging whereby heat is conducted through -23 -an otherwise well insulated structure via heat conductive fixings. This principle applies to all of the dowel ccnnections described herein.

Figures lSA to l5C show one way in which doors and windows may be fitted to a structure. Part of a structure 1700 is shown in Figure iSA comprising a plurality of structural beams 1710 arranged to form a floor 1705 arid wall 1706. The beams 1710 of the wall 1706 are arranged to define a door or window opening 1707. A lintel (not shown) would typically be placed over the top of the door or window opening 1707.

Figure 1SB shows a door or window frame 1708 comprising four frame boards 1701. The frame boards 1701 are sized and arranged to fit within the door/window opening 1707. The frame boards 1701 may be jointed in any suitable manner including abutment or rebate joints and may be glued or screwed together.

The external surfaces of the frame boards 1701 comprise grooves 1709 which are sized and arranged to lie in registration with grooves 1716 on the outer edges of the wall beams and grooves 1715 formed across the edge of the floor beams. In this example the grooves 1709, 1715 and 1716 are provided in pairs. Alternatively, the grooves 1709, 1715 and 1716 may be provided as singles, triples or more, or any combination thereof.

The internal surfaces of the frame boards 1701 comprise a single groove 1711 which lies in registration with a groove 1712 on the external edge of the door or window as -24 -described below. If desired, a pair, or more, of grooves 1711 may be provided.

Figure 15C shows a window unit 1703. The external edges of the window unit 1703 comprise grooves 1712 which are arranged to lie in registration with the grooves 1711 of the frame boards when assembled.

When assembled, the door/window frame 1708 is positioned in the door/window opening 1707 so that the grooves 1711, 1715 and 1716 lie in registration. Sealing strips 1702 are placed in the grooves 1711, 1715 and 1716 to provided an air tight seal. The window unit 1713 is placed within the frame 1708 so that the grooves 1712 lie in registration with the grooves 1711. Sealing strips 1704 are placed in the grooves to provide an airtight seal. The sealing strips 1702, 1704 may comprise any suitable insulating material such as OSB, recyclable plastic or rubber. In one example, the sealing strips may comprise intumescent material.

In the case where a door is to be fitted rather than a window, the door replaces the window unit 1703. The door can be any suitable door but preferably the door has a similar construction to the beams 10 or 1010 described above. The doors may be multi or single core.

In the panels and structures described above, rails 20 have been placed in the grooves 16, 1016, 1616 to provide location and connection between adjacent beams. Any of the rails 20 described above may optionally be replaced by sealing strips to provide enhanced sealing. In particular, -25 -sealing strips may advantageously be used between the tops and bottoms of walls and the adjoining floors/roofs.

Figures 1GA and 1GB illustrate beams 1720 comprising surface grooves 1715 for receiving sealing strips 1702.

Corresponding grooves (not shown) are provided in the stiffening ribs at the ends of the wall beams to accommodate the sealing strips. As shown in Figure 16A, at the corner of a structure/room, the grooves 1715 intersect one another.

Pairs of grooves 1715 are shown in the Figures, however any number of grooves may be used as desired.

Figure 17 illustrates an alternative beam configuration. As with the beams described above, beam 1810 comprises two face layers 1811, 1812 and two edge layers 1813, 1814 jointed together by rebate joints which are glued and/or screwed together. Beam 1810 further comprises webs 1815 which are located within the beam such that they are parallel to, and spaced from, the edge layers 1813, 1814.

The webs 1815 are jointed to the face layers 1811, 1812 by housing joints. As with beams 10 above, beam 1810 comprises two grooves 1816 in the outer surfaces of each edge layer 1813, 1814 for receiving rails 1820. Insulation 1817 resides in insulation spaces 1818 defined by the webs 1815.

The beams 1810 may be used in exactly the same way as described above for the beams 10. In the example shown in Figure 17, the beam 1810 is bounded on one side by additional insulation 1821. This insulation may be placed between the beams in any structure or panel as described above. In the case where additional insulation is placed between beams, the rails 20, 1820 may be wider to accommodate the thickness of the insulation.

-26 -Figure 17 also shows facing boards 1823 located on either side of the beam 1810. Additional insulation 1822 is located between the face layers 1811, 1812 and the facing boards 1823. The facing boards 1823 may be the covering of a floor or wall, or may be the panel facing boards of a structural panel. As above, the beams may be connected side by side by dowels 1601 as shown in Figure 12, and dowels may be used to connect the facing boards to the underlying face layers as described above with respect to Figures 5 and 7.

Figure 18 shows a panel 1850 comprising beams 10 as described above arranged with additional insulation 1821 between the beams, and additional insulation 1822 between the face layers 11, 12 and the panel facing boards 1823.

All components may be glued and/or screwed together. OSE rails 1820 are placed in grooves 16 to located and join the beams 10. In an alternative example (not shown) no rails 1820 are used between the beams 10.

Figure 19 shows an additional stiffening board 1860 which may be used instead of, or in addition to, the additional insulation 1821 between the beams in a structure or panel. Figure 19 illustrates two edge layers 13, 14 of adjacent beams 10. The additional stiffening board 1860 comprises grooves 1862 on each side face which are arranged to lie in registration with grooves 16 in the edge layers 13, 14. Rails 1861 are placed in the grooves 16, 1862 to locate and connect the edge layers to the additional stiffening board 1860. The additional stiffening board 1860 may be made from any suitable material such as OSB, engineered wood, aluminium or steel. The additional stiffening boards 1860 shown in Figure 19 do not include -27 -dowel holes, however, dowel holes may be included if desired to allow side to side dowel connection of the beams.

Figures 20A and 20E show a face layer 11 and an edge layer 14 of a beam 10. A steel-T section 1900 is located at the exterior corner of the joint between the face layer 11 and the edge layer 14. The steel-T 1900 is located in a rebate cut into the exterior surfaces of the face and edge layers 11, 14 so that the base of the T is flush with the exterior surface of the face layer 11, and so that the leg of the T is half way embedded in the edge layer 14. As shown in Figure 20B, one end of the steel-T may be formed so that there is a substantially flat surface 1901 which lies in a rebate in the ends of the face and edge layers 11, 14 so that the surface 1901 is substantially flush with the end of the beam.

A beam (not shown) to be placed adjacent to the beam comprising the steel-T 1900 will comprise complimentary rebates to allow the steel-T to be received, thus allowing a flush connection between beams. Alternatively, the steel-T 1900 may be received in rebates formed in additional insulation or stiffening between beams. Although only one steel-T 1900 is shown in Figures 20A and 20B, it will be appreciated that steel-Ts could be used at any and/or all corners of the beams. The steel-Ts 1900 may be of any suitable length such as the length of the beam, the length * of a panel or the length of a floor/roof span. The steel-Ts provide additional strength to the structures/panels and may be incorporated into any of the structures/panels described herein.

-28 -The structural beams of the present invention may also be used as support posts in a structure having non-structural walls. For example, glass walls. An example structure is shown in Figure 21. The structure 2000 comprises upper 2101 and lower 2100 floors. The upper floor 2101 is supported on lintel beams 2300 which are themselves supported on load bearing walls 2200 and vertical beams 2010. Open spaces 2050 are left in the structure to be closed by glass walls or any other suitable non-load bearing closure.

If desired, any structure made up of beams/panels according to the present invention may be fully demountable so that it may be erected at one location, dismantled, and re-erected at another location. One way of achieving this is illustrated in Figures 22A and 223. Referring first to Figure 22A, an exploded view of part of a structure 2500 is shown comprising a vertical beam 2510, two lintel beams 2300 and a beam 2511 forming part of an upper floor. The structure of the beams 2510, 2300, 2511 shown in Figure 22A is substantially the same as described above with respect to beams 10. However, in the structure 2500 the beams 2510, 2300, 2511 comprise grooves 2516, 2515, 2518 which are wider and/or deeper than the corresponding grooves 16 in the beams 10. similarly, the diameter of the dowel holes 2602 in the beam edge layers are larger than the diameter of the dowels 2601 which pass through them. This increase in groove/hole dimensions is provided to allow edge seals 2517 to be located along the periphery of the grooves/holes. This allows sufficient room for aligning rails 2520 to be positioned in the grooves 2516, 2515, 2518 to align and connect the various beams whilst providing sufficient -29 -sealing. Similarly, the enlarged dowel holes 2602 allow sufficient room for the seal 2517 to surround the connecting dowels 2601 without blocking the holes.

The various parts of the structure 2500 are connected by steel bolts 2530, 2531, 2532 and 2533 which pass through the beams of the structure. In Figure 22A, the floor beam 2511 is connectd to the lintel beam 2300 by a steel bolt 2530 and the lintel beam 2300 is connected to the vertical beam 2510 by a steel bolt 2531. Similarly, the vertical beam 2510 is connected to an adjacent beam 2510 (shown in part) by a steel bolt 2533. An additional steel bolt 2532 connects the two lintels 2300. The steel rod 2533 passes through the face layers of one lintel beam and through the stiffening ribs of the adjacent lintel via hole 2560. As shown in Figure 22A, the steel bolts 2530, 2531, 2532, 2533 may pass through the dowels 2601. In particular, the steel bolts may pass through a central bore 2561 formed in the dowels 2601.

Figure 22B shows an alternative view of the structure 2500. In this view it can be seen that dowel holes 2603 are elongated to facilitate assembly of the structure. The structure is assembled by erecting one end or side wall, then adding two side or end walls, and finally fitting the final end or side wall. The walls are lowered by crane until the dowels fit into the elongated dowel holes 2603.

The wall is then moved sideways to let the dowel fit into the hole at full depth before the wall is gently lowered until the dowels 2601 and aligning rails 2520 align and fit.

-30 -Conduits, pipes and ducts may be incorporated into the structures/panels as desired. These may either be installed into the prefabricated structure in the factory or installed on site. The conduits/pipes/ducts may carry electrical wiring, water pipes, waste pipes and air heating/cooling.

The conduits/pipes/ducts may advantageously be run through the structures/panels inside the insulation spaces within the beams or through any additional insulation used between beams or between the beams and facing board layers. Of particular convenience may be to run conduits/pipes/ducts through the dowel holes in place of the interconnecting dowels. Any of the structures/panels may comprise sealable vents to allow/prevent the ingress/egress of air, smoke etc through ducts in the structure/panels to the exterior of the building. Air ducts may advantageously be deliberately turned through angles to allow the ingress of fresh air from outside without the force of the wind reaching the interior of the structure. If desired, heating air may be circulated through the walls of a structure either through spaces specifically designed for such use, or through insulation spaces which contain no, or open cell, insulation. The panels/structures may be pre-fitted with electric lights or power sockets or the like.

Floors of the structure may be fabricated with an incline to allow waste water to flow towards a drain.

Alternatively or additionally, the floors may be fabricated with different depths. Such an arrangement would be particularly suitable in a shower/wet room.

The floors, roofs, walls and panels of any of the structures described above my be covered with any suitable -31 -covering or coating including SIPs, brick slips, paints, phase change materials, water-proof coatings, tiles etc. In all of the structures described above the beams are arranged side by side so that their edge layers are substantially pa±allel and face one another. If desired, the beams can be used in an orientation whereby the face layers are substantially parallel and face one another.

Although, not a preferred way to se the beams, there is nothing to prevent the beams being used in this way.

Similarly, the beams of wall or roof constructions can be placed with their longitudinal axes in a horizontal orientation if desired. This may be particularly suitable for party wall arrangements.

Claims

-32 -Claims: 1. A structural beam having a cross-sectional width to depth ratio in the range 0.25 to 4, the beam comprising: first and second face layers; first and second edge layers; and at least one web, wherein the at least one web is located within the beam and arranged such that it is substantially parallel to and spaced from either the first and second face layers, or the first and second edge layers, to define at least two insulation spaces within the beam.
2. A structural beam as claimed in claim 1, further comprising insulation material located in at least one of the insulation spaces.
3. A structural beam as claimed in any preceding claim, further comprising stiffening ribs at least partially located within each end of each insulation space, wherein the stiffening ribs substantially close the ends of the insulation spaces.
4. A structural beam as claimed in any preceding claim, wherein the first and second edge layers comprise engagement features to facilitate engagement with adjacent structural beams in use.
5. A structural beam as claimed in claim 4 wherein the engagement features comprise at least one groove in the exterior surface of each of the first and second edge layers.

-33 -
6. A structural panel comprising a plurality of structural beams, each beam having a cross-sectional width to depth ratio in the range 0.25 to 4 and comprising: first and second face layers; first and second edge layers; and at least one insulation space, the beams being arranged side by side such that the edge layers of adjacent beams are substantially parallel and face one another, the panel further comprising at least one panel facing board located over the face layers of at least two adjacent beams.
7. A structural panel as claimed in claim 6, wherein the at least one panel facing board partially overlaps a first beam and partially overhangs a second beam.
8. A structural panel as claimed in claim 6 or 7, wherein adjacent beams are engaged with one another via engagement features located on the exterior surfaces of the edge layers.
9. A structural panel as claimed in claim 8, wherein the engagement features comprise at least one groove in the exterior surface of each of the edge layers, the panel further comprising rails located within the grooves.
10. A structural panel as claimed in any one of claims 6 to 9, wherein the beams are longitudinally offset with respect to one another.

-34 -
11. A structural panel as claimed in any one of claims 6 to 10, comprising beams in accordance with any one of claims 1 to 5.
12. A floor, a roof or a wall comprising a plurality of structural panels as claimed in any one of claims 6 to 11 arranged in an array.
13. A wall comprising a plurality of structural beams, each beam having a cross-sectional width to depth ratio in the range 0.25 to 4 and comprising: first and second face layers; first and second edge layers; and at least one insulation space, wherein the beams are arranged side by side such that the edge layers of adjacent structural beams are substantially parallel and face one another.
14. A wall as claimed in claim 13, further comprising a coping beam located at the top of the plurality of beams, wherein the coping beam is supported by at least two of the plurality of beams.
15. A wall as claimed in claim 14, wherein one or more of the structural beams or coping beam comprise a structural beam in accordance with any one of claims 1 to 5.
16. A floor, a ceiling or a roof comprising a plurality of structural beams arranged in an array, each beam having a cross-sectional width to depth ratio in the range 0.25 to 4 and comprising: first and second face layers; -35 -first and second edge layers; and at least one insulation space, wherein the beams are arranged such that the edge layers of adjacent structural beams are substantially parallel and face one another.
17. A floor, a ceiling or a roof as claimed in claim 16, wherein the array comprises a plurality of beams arranged end to end.
18. A floor, a ceiling or a roof as claimed in claim 16 or 17, comprising a plurality of beams in accordance with any one of claims 1 to 5.
19. A structure comprising a plurality of structural beams as claimed in any one of claims 1 to 5, a plurality of structural panels as claimed in any one of claims 6 to 11, one or more walls as claimed in any one of claims 13 to 15, or one or more floors, ceilings or roofs as claimed in any one of claims 16 to 18.
20. A method of forming at least part of a structure comprising arranging a plurality of structural beams as claimed in any one of claims 1 to 5 in an array.
21. A method of forming at least part of a structure comprising placing a plurality of structural panels as claimed in any one of claims 6 to it in an array.
22. A method of forming at least part of a structure comprising forming a wall as claimed in any one of claims 13 to 15.-36 -
23. A method of forming at least part of a structure comprising forming a floor, a ceiling or a roof as claimed in any one of claims 16 to 18.