GB2455360A - Timber-framed building structures - Google Patents

Abstract

The invention relates to a timber frame structure for a building 10, 12 and 14 e.g. a house, comprising elongate base members (32 and 34 figure 2) extending along lines of respective walls of the building, corner posts 16, 18, 20 and 22 extending upwardly from the base members at intersections of respective walls, elongate head members 24 and 26 extending between the upper end parts of the corner posts; and a plurality of wall panels 70, 72, 74, 76, 78 80 and 82 extending between the head and base members to provide walls for the structure. The wall panels are preferably selected from a number of standard panels. A later embodiment relates to a method of constructing said timber frame structure.

Description

Title: Timber-Framed Building Structures

Description of Invention

This invention relates to timber-framed building structures.

The timber-framed construction is well known for use in relatively small buildings such as houses, offices, hotels and others, and has many advantages when compared with traditional constructional techniques wherein the load-supporting walls of a building are constructed of bricks and/or blocks.

One such advantage is speedy construction and another such advantage is that a timber-framed house can be highly energy efficient compared with one of traditional construction. Timber itself has good thermal insulation properties, and a wall constructed of timber-based materials, with suitable insulating materials, can be highly insulative. Indeed, future requirements for effectiveness of insulation in houses will mean that timber-framed construction becomes much more widely used, to the extent that virtually all newly-built houses will need to be of this type if they are to comply with the applicable regulations. At the same time, timber-framed walls have adequate stability and strength to support the weight of the floors and roof of small buildings as aforesaid, of up to about six storeys, and, when suitably treated and finished using materials such as plasterboard, have sufficient durability including resistance to damage by fire.

In general, timber-framed houses hitherto have taken the design of traditionally-constructed buildings as a starting point, the timber framework being designed and the necessary structural calculations carried out to suit the shape and dimensions of the required building. Components of the timber structure are then factory-made to the required dimensions, and prefabricated into structural sub-assemblies which can be transported to a construction site and erected to form the building. On site, a foundation, for example a concrete raft, is constructed at the required position, and scaffolding erected to enable the timber framework then the rest of the building to be constructed.

Whilst such construction methods enable buildings to be erected quickly compared with traditional constructional techniques (the erection of the timber framework for a timber-framed house might only take a few days) there are disadvantages. One is that from the design and structural engineering viewpoint all the buildings are to some extent individual, so that although some common components can be utilised the extent to which this can be achieved is limited. For each variation in size and design of a house new structural calculations have to be performed and components manufactured to suit the relevant dimensions. It would be desirable if more use could be made of common components, and the need for individual calculations reduced or eliminated, when designing different buildings.

On site, once a foundation has been established, the scaffolding has had to remain in situ not only during the erection of the basic timber framework of the building but during all subsequent building stages including the construction of cladding walls (which may be traditionally built of masonry, i.e. bricks/blocks), roofing, and the installation of high-level external fittings such as guttering and downpipes. Indeed, the scaffolding will have to be reconfigured between the erection of the timber-framed structure and the construction of cladding walls, being disposed further away from the timber-framed structure for the latter operations. Further, fall-arrest systems such as special-purpose airbags have to be provided inside the timber framed structure, until such time as internal floors have been installed. These requirements are expensive.

It is broadly the object of the present invention to address one or more of the above mentioned disadvantages of previously-known timber-framed structures for buildings such as houses. The manner in which the present invention, in its various aspects, deals with this will be described in greater detail hereafter.

According to one aspect of the invention, we provide a timber frame structure for a building, comprising: elongate base members extending along the lines of respective walls of the building; corner posts extending upwardly from the base members at intersections of the respective walls; elongate head members extending between the corner posts at upper end parts thereof, above the base members; and a plurality of wall panels extending between the head and base members to provide walls for the structure.

The wall panels may comprise selected ones from a number of standard panels, which can be placed in relation to one another to provide a length of wall corresponding to each distance between the corner posts.

At least some of the wall panels may be able to overlap one another in the direction lengthwise of the head and base members, to accommodate changes in the distance between the upwardly extending edges of the panels which are remote from one another.

Each wall panel may comprise spaced elements of timber which are upright in use, extending between the head and base members, and a board material connected to the upright elements on one side thereof to provide a wall surface between the head and base members. Preferably the board material of each panel has upper and lower edge portions which extend to cover (at least partially) corresponding side surfaces of the head and base members respectively, and are secured to the head and base members to fix the panel in position.

To provide for the adjustment of the position of adjacent wall panels relative to one another in the direction lengthwise of the head and base members, a panel may include a board portion which extends beyond an upright element at an upright edge of the panel, so that it can overlap with the upright edge of the board portion of an adjacent panel, which is disposed to the opposite side of the head and base members to the board material of the first-mentioned panel.

Each head member may comprise an I-beam, with timber chords and a web, oriented with its chords spaced vertically above one another and its web extending substantially vertically therebetween.

The lower chord of such a head member may be arranged to form a lintel where door or window openings are to be provided in the wall. The corner posts may have portions arranged to support the lower chord of the I-beam at a suitable height for this purpose.

Each head member may comprise two of the I-beams disposed one on top the other in the same orientation as one another. The upper I-beam may provide support for an elongate base member and corner posts to form another storey above the first-erected storey of the building, and for joists for a floor of the upper storey.

Each wall panel may comprise an insulation material, preferably provided on a side of the board material to lie between the upright elements of the panel.

Such an insulation material may comprise, for example, an expanded polyurethane type of material, of a suitable thickness, e.g. 100 mm or greater for higher insulating qualities. A vapour barrier, e.g. a membrane of sheet plastics material, would also be incorporated where the wall panel is for an exterior wall of a building. Where adjustment of the position of adjacent panels is required, the insulation material would be removed as necessary from the board material which is required to extend beyond the edge of the adjacent panel.

In a building structure in accordance with the invention, the corner posts and head members may be dimensioned such that a predetermined maximum span of e.g. 10 metres between adjacent corner posts is acceptable. For any smaller span, the head member may be stronger than is necessary, but this is not disadvantageous since it enables a head member of cross-sectional shape and dimensions suitable for the 10 metre span to be used for all spans up to that limit. If the length of a wall between respective walls extending in different directions exceeds the limit, the same cross-sectional dimensions of head member could still be utilised but an additional upright member, analogous to a corner post, would have to be utilised between the ends of the wall to support a first head member and a further one of the required additional length. If the internal space of the building is divided by an internal wall, the additional upright member would be disposed where the internal wall is required to join the external wall. Any internal walls required in the building would be of analogous construction to the external walls utilising head and base members, and wall panels providing for length adjustment in the direction lengthwise of the internal wall, in the same manner as the panels for external walls.

The head members for a lower storey of the building, which carry the base members for a superposed storey, may be connected together to form a ceiling and floor sub-assembly for the lower and upper storeys respectively, which sub-assembly can be constructed away from the building structure and placed in situ as a unit. Similarly, at the top of the highest storey in a building, head members each comprising a single I- beam may be assembled together with a timber roof structure to form a ceiling and roof sub-assembly which can be fitted as a unit. Such sub-assemblies may be placed in position on a building by use of a crane.

In order to create a building structure in accordance with the invention, the first step, performed on site, would be to install a foundation, for example a concrete raft, of the required overall size of the building. Base members for the external and any required internal walls of the building would then be placed in position on the foundation, and corner posts and any necessary additional upright member positioned at the intersections of the respective external, and any internal, walls. They would be secured to the base members, and supported in the required upright orientation.

Head members, preferably of the configuration above set forth each comprising two I-beams disposed one above the other, would then be assembled to one another in the required positions to form a sub-assembly of the head members for all the walls of the building. Such assembly would not be carried out in situ, but rather at a convenient location near the positioned upright members, e.g. on the ground nearby. This sub-assembly is preferably also provided with joist members to provide flooring for the next storey of the building. Preferably the joists are boarded with floor boards. The entire sub-assembly of head members, joists and floor boarding can then be moved by crane to be positioned as required on the corner posts.

After the sub-assembly of head members, joists and floor boarding has been positioned, the panels forming the walls of the structure can be fitted between the head and base members. Each panel is fitted individually, with appropriate use of panels which can overlap one another as aforesaid in the case where the length of a wall does not permit the use of panels disposed end to end with one another.

Prior to being lifted into position, the sub-assembly of head members and joists for the ceiling structure of the lower storey and floor structure of the upper one may be provided with hand rails so that construction personnel can work on the erection of the structure for the upper storey from the floor structure thereof without requiring any external scaffolding or other safety systems. The hand rails may be secured to the respective head members, to remain in position until their removal is necessitated by the construction of external walls, e.g. of brick outside the timber-framed structure.

Internally of the timber-framed structure, plasterboard would be fitted to the inside surface of the timber frame panels, and to the ceiling beneath the joists of the assembly of head members.

The construction of the next storey of the building would then be commenced by the positioning of corner posts at the intersections between respective external and internal walls of that storey, such corner posts being secured and supported in the upright position relative to the base members fitted to the sub- assembly of head members at the top of the lowermost storey. A sub-assembly of head members for the upper storey would, if this is the uppermost storey, be constructed with a roof truss structure which can be moved into place by a crane. The fitting of wall panels to the walls of this upper storey can, on the inside of the timber framed structure, be carried out from the floor which has been fitted with the head members to the tops of the corner posts of the lower storey, while panels fitted in the exterior of the timber framed construction can be fitted from the scaffolding erected as aforesaid.

Plasterboard to provide the finish of the walls of the upper storey, and for the ceiling thereof, can be fitted to the timber framed structure and to the roof truss structure by standing on the floor of the upper storey, i.e. no scaffolding nor fall-protection systems are required in the interior of the building.

Thus far, if hand rails have been utilised as aforesaid, the erection of the structure has been carried out without requiring the use of scaffolding. Suitable scaffolding would then be erected around the timber-framed structure to enable external walls of bricks, for example, to be built up outside the timber framed structure.

The scaffolding would be raised in height as necessary as the construction of the external walls proceeds.

The invention also provides a method of constructing a timber frame structure for a building utilising the elements of the first aspect of the invention as above described.

The use of a timber frame structure according to the invention, as above described, enables a timber-framed building to be erected extremely rapidly compared with timber-framed building structures and techniques known hitherto. For example, it is estimated that the entire timber frame structure for a relatively small building, e.g. a house with a floor area of about 1000 sq ft, could be erected in a single working day. Since the timber frame structure can be erected as above-described without the use of scaffolding, the time for which scaffolding has to be on site and erected is substantially reduced. Also, there is no requirement for dismantling or partial dismantling of erected scaffolding and re-erecting thereof in a different configuration between the stages of building the timber frame structure and building external walls of brick. Scaffolding might be required to be in use for only, approximately, half the length of time it has been necessary for previously-known timber-framed constructional techniques.

The invention will now be described by way of example only with reference to the accompanying drawings, of which: Figure 1 is a perspective view of an embodiment of timber framed structure, in accordance with the invention; Figure 2 is a perspective view of elements of the lower storey of the structure; Figure 3 is a perspective view of a corner post of the structure; Figures 4, 5 and 6 are perspective views of wall panels for use in the structure; Figures 7, 8 and 9 are perspective views illustrating the disposition of wall panels in relation to one another in a structure; Figures 10 and 11 are perspective views and elements and assemblies of the building structure in accordance with the invention.

Referring firstly to Figures 1 and 2 of the drawings, this shows a timber-framed building structure in accordance with the invention. The structure is for a building (e.g. a house) having two storeys, namely a lower storey 10 and an upper storey 12, surmounted by a pitched roof structure 14. Corner posts for the lower storey 10 are visible at 16, 18 respectively, and for the upper storey at 20, 22. A head member for the visible wall of the lower storey 10 is indicated at 24, which is incorporated as described hereafter in an assembly which also forms the floor of the upper storey 12. A head member for the visible wall of the upper storey is indicated generally at 26, and this head member supports the roof structure 14. The entire structure is constructed on a foundation 30 such as a concrete raft, and on this foundation are supported elongate base members upon which the walls of the structure are carried and accordingly which extend along the lines of such walls. Two adjacent such base members, meeting at the corner post 16, are visible at 32, 34 respectively.

Figure 2 of the drawings shows one of the corner posts 16 or 18 of the lower storey 10. The corner post 16 is shown in greater detail in Figure 3. It comprises two generally U-shaped members 36, 38 disposed at right angles to one another, the member 36 comprising two spaced parallel upright timber elements 40, 42 joined by a board element 44, e.g. of plywood, which extends above the upper ends of the members 40, 42 and a small distance below the lower ends thereof. Similarly the member 38 comprises timber elements 46, 48 and a board element 50, e.g. of plywood connecting the timber elements 46, 48 and also extending above the level of the upper ends of such elements and a small distance below the level of the lower ends of such elements.

Further timber members 52, 54 are disposed to occupy the right-angled corner between the members 42, 46, and suitable fastening elements secure these components together as illustrated.

In Figure 2, it will be seen that the bottom ends of the timber members 40, 42 rest on the base member 34, and the bottom ends of the timber members 46, 48 likewise rest on the base member 32. The lowermost edges of the board elements extend down to the top surface of the foundation 30.

The tops of the corner posts at the intersections of the walls of the building are joined by respective head members. As seen in Figure 1, the tops of the corner posts 16, 18 are joined by a head member comprising an I-beam 60 above which is a further I-beam 62. The lower I-beam 60 is seen in isolation in Figure 7 of the drawings, and it will be noted that it comprises upper and lower chords 64, 66 extending parallel to one another and secured together in such relationship by an upright web 68 extending there between. The upper I-beam 62 is of the same configuration, its lower chord being connected to the upper chord 64 of the I-beam 60. The assembly of I-beams 60, 62 is used in providing an assembly which forms the basis for the ceiling of the room or rooms forming the lower storey 10 and the floor for the upper storey 12. The lower I-beam 60 is supported on the uppermost ends of the upright members 40, 42, 46, 48 and 52, 54, of each of the corner posts.

The timber frame structure further comprises wall panels which fit between the base member and head member of each respective wall of the structure. In Figure 1 the visible wall of the lower storey of the building has a number of wall panels indicated at 70, 72, 74, 76, 78, 80 and 82. These panels are selected ones of a number of standard panels.

Firstly, the panels 70, 72, 74, 76 and 78 are each as shown in Figure 6. This comprises a board 90 of plywood, to which are secured three spaced parallel upright timber stud elements 92, 94, 96. The board 90 extends above the level of the stud elements and below the bottoms thereof, in the same manner as the board elements 44, 50 of the corner post shown in Figure 3. A further type of wall panel is shown in Figure 5, which comprises a board element 98 and two stud elements 100, 102. This panel, used as the panel 82 in the wall shown in Figure 1, is as the panel of Figure 6 but of only half the width thereof.

Yet a further panel is shown in Figure 4. This is as the panel of Figure 6, having a board member 104 of the same dimensions but with only two stud elements 106, 108 of which the later is disposed centrally of the board member and the former at one edge. The stud element 106 could be disposed at the opposite edge of the board member 104 so as effectively to make a left-handed or a right-handed panel according to the edge at which it is disposed.

A panel with the stud element 106 at the opposite edge to that where it is shown in Figure 4 is used as the panel 76 in the wall visible in Figure 1.

Finally, the panel 80 in Figure 1 is as the panel 6 but is cut off at a suitable height above its lowermost end to provide an opening above it for installation of a window.

Although not shown in the illustration, each of the panels above described would also incorporate thermal insulation, e.g. of plastics material such as polyurethane foam, occupying the space between the stud elements of the panel. A vapour barrier, e.g. a plastics membrane, would also be included so that the wall has, in addition to the required thermal insulation, appropriate resistance to passage of water vapour across the wall.

Figures 7, 8 and 9 illustrate the manner in which, in the erected timber frame structure, the wall panels as above described fit in relation to the base and head members 34 to form the walls. Figure 7 shows a panel as shown in Figure 6, with its stud elements 92, 94, 96 extending between the base member 34 and the lowermost chord of head member 60. The board 90 of the panel, where it extends below the lower ends of the stud elements, lies against the side face of the base member 34 while where the board extends above the upper ends of the stud elements it lies against the side of the lower chord 66 and up to the upper chord 64.

Figure 7 shows another panel which is of a type shown in Figure 4, arranged with its board (104) on the opposite side of the base member and the head member to the board 90 of the first panel. Because there is no stud element at the visible upright edge of the board 104, the board 104 is able to overlap the first panel in the direction lengthwise of the base element and head member, up to the point at which the stud element midway between the upright edges of the panel abuts the stud element 96 of the first panel, thereby allowing some adjustment in the total distance between the upright edges of the two illustrated panel.

Referring now to Figures 8 and 9 of the drawings, these show diagrammatically, a base member 34, a head member 60, a panel as shown in Figure 6 whose board is illustrated at 90, and a panel as shown in Figure 4 (but of opposite hand) whose board is indicated at 104 and stud elements at 106, 108. In figure 9, the panel 104, 106, 108 has been slid towards the first panel until it overlaps therewith to virtually the full extent of the board 104 which extends beyond the stud element 108. To enable this to be done, of course, an appropriate amount of insulation has to be removed from the board 104 (although it will be appreciated that no insulation is shown in these figures in any event).

In Figure 1, a space is shown between panels 76, 78. This space may be dimensioned to fit the fixed peripheral frame of a door. Suitable adjustment between the relative positions of panels 74, 76, in the manner shown in Figures 8 and 9, enables the space between the panels 76, 78 to be adjusted to match the width of the door frame.

Hence, whatever is the length of a wall of a timber frame structure, and whatever windows and doors might be included in it, it can be constructed by using a small number of "standard" panels. The head member extends between corner posts at the end of the wall, and provides the lintel above each door and window opening.

Internally of the building, the walls would be finished by the application thereto of plasterboard sheets which can then be plastered, as is done for known timber-framed building structures. Where, on the interior surface of the timber-framed structure, one or more stud elements of wall panels are presented without a covering board, a timber filling element of thickness corresponding to the ply-wood boards of the wall panels has to be secured to each stud element so as to present a surface co-planar with the surface of the ply-wood boards to which the plasterboard can be fixed.

The dimensions of a head member 60, 62 are selected so as to provide adequate structural strength for a wall up to a predetermined length, e.g. 10 metres between corner posts. If a building has a wall longer than this, an additional supporting post or posts may be provided between the corner posts at the ends of the wall, and an additional head member or members of suitable length used. Where a building has one or more structural internal walls, a supporting post analogous to a corner post would be provided where an internal structural wall intersects the external wall of the structure.

Referring now to Figure 10 of the drawings, this shows the lower storey of the timber frame structure, with one wall thereof being seen in detail with a head member comprising two I-beams 120, 122 supported on the ends of the upright members of corner posts at the ends of the wall, and with wall panels in position to provide the timber wall structure with suitable openings for a window and a door. As above described, the lower I-beam 120 of the head member forms the lintels above the doors and window openings. The upper I-beams on opposite sides of the structure have a plurality of spaced parallel joist members as indicated at 124 extending between them to provide a support for floor boarding for the upper storey of the building and to provide for attachment of plasterboard to form a ceiling of the lower storey. The joists 124 may be secured to the opposite I-beams by conventional joist hangers.

Figure 10 also shows that the upper I-beam 122 has secured to the upwardly-facing surface of its upper chord a timber member 126 which forms a base member for the support of corner posts for the upper storey of the structure and for panels to form the wall of that structure. The panels used for the upper storey are the same as for those used for the lower storey, and they are assembled in the same manner as for the lower storey in relation to the base members, corner posts, and head members to form the upper storey. Further storeys of the same configuration could be provided, up to, perhaps, six storeys.

Figure 11 shows a roof truss assembly for the structure, It includes two I-beams 130, 132 which form the head members extending between respective corner posts on opposite sides of the structure. These I-beams are identical to the I-beams 60, 62 and the other I-beams used in the head members of the structure. The beams 130, 132 are joined by a number of spaced parallel joists 134 whose ends are secured to the upper chords of the respective I-beams. The roof structure further comprises rafters 136 and upright and inclined braces 138, 140, all arranged in known manner for such roof structures. In installation of the roof structure, as a final or near-final stage of the erection of the timber frame structure as above described, the structure shown in Figure 11 would be constructed on site at ground level from the respective components as above described. The head members in the form of I-beams 130, 132 for the one pair of opposite walls of the building structure would be assembled with the roof as shown in Figure 11, while the head members of the other pair of opposite walls of the structure would be fitted to the tops of the respective corner posts.

The complete roof assembly, as shown in Figure 11, would then be lifted by crane to be fitted on top of the previously-erected roofless structure.

To construct a timber-framed building structure in accordance with the invention, the first stage to be conducted on site is the preparation of a foundation, e.g. a concrete raft, upon which the base members for the walls of the lower storey would be installed. The corner posts would be connected to the base members where the external walls (and any internal walls) meet, and temporarily supported in an upright orientation.

A structure forming the head members to be supported on the corner posts of the lower storey would be constructed on site at ground level, including the joists which carry the floor of the upper storey and ceiling of the lower storey, and lifted by crane to be positioned as shown in Figure 10, this structure including the base members for the walls of the upper storey. It is then possible to install the panels forming the walls of the lower storey, extending between the base members and head members thereof. Construction of the upper storey including its corner posts, roof structure as above described, and finally panels forming the walls of the upper storey can then be undertaken.

Scaffolding can then be erected for use in building cladding walls, e.g. of brick, roofing, and other external operations at high level. It will be appreciated that such scaffolding is required for much less time than it has to be in place for previously-known timber framed buildings.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof. Title: Timber-Framed Building Structures

Description of Invention

This invention relates to timber-framed building structures.

The timber-framed construction is well known for use in relatively small buildings such as houses, offices, hotels and others, and has many advantages when compared with traditional constructional techniques wherein the load-supporting walls of a building are constructed of bricks and/or blocks.

One such advantage is speedy construction and another such advantage is that a timber-framed house can be highly energy efficient compared with one of traditional construction. Timber itself has good thermal insulation properties, and a wall constructed of timber-based materials, with suitable insulating materials, can be highly insulative. Indeed, future requirements for effectiveness of insulation in houses will mean that timber-framed construction becomes much more widely used, to the extent that virtually all newly-built houses will need to be of this type if they are to comply with the applicable regulations. At the same time, timber-framed walls have adequate stability and strength to support the weight of the floors and roof of small buildings as aforesaid, of up to about six storeys, and, when suitably treated and finished using materials such as plasterboard, have sufficient durability including resistance to damage by fire.

In general, timber-framed houses hitherto have taken the design of traditionally-constructed buildings as a starting point, the timber framework being designed and the necessary structural calculations carried out to suit the shape and dimensions of the required building. Components of the timber structure are then factory-made to the required dimensions, and prefabricated into structural sub-assemblies which can be transported to a construction site and erected to form the building. On site, a foundation, for example a concrete raft, is constructed at the required position, and scaffolding erected to enable the timber framework then the rest of the building to be constructed.

Whilst such construction methods enable buildings to be erected quickly compared with traditional constructional techniques (the erection of the timber framework for a timber-framed house might only take a few days) there are disadvantages. One is that from the design and structural engineering viewpoint all the buildings are to some extent individual, so that although some common components can be utilised the extent to which this can be achieved is limited. For each variation in size and design of a house new structural calculations have to be performed and components manufactured to suit the relevant dimensions. It would be desirable if more use could be made of common components, and the need for individual calculations reduced or eliminated, when designing different buildings.

On site, once a foundation has been established, the scaffolding has had to remain in situ not only during the erection of the basic timber framework of the building but during all subsequent building stages including the construction of cladding walls (which may be traditionally built of masonry, i.e. bricks/blocks), roofing, and the installation of high-level external fittings such as guttering and downpipes. Indeed, the scaffolding will have to be reconfigured between the erection of the timber-framed structure and the construction of cladding walls, being disposed further away from the timber-framed structure for the latter operations. Further, fall-arrest systems such as special-purpose airbags have to be provided inside the timber framed structure, until such time as internal floors have been installed. These requirements are expensive.

It is broadly the object of the present invention to address one or more of the above mentioned disadvantages of previously-known timber-framed structures for buildings such as houses. The manner in which the present invention, in its various aspects, deals with this will be described in greater detail hereafter.

According to one aspect of the invention, we provide a timber frame structure for a building, comprising: elongate base members extending along the lines of respective walls of the building; corner posts extending upwardly from the base members at intersections of the respective walls; elongate head members extending between the corner posts at upper end parts thereof, above the base members; and a plurality of wall panels extending between the head and base members to provide walls for the structure.

The wall panels may comprise selected ones from a number of standard panels, which can be placed in relation to one another to provide a length of wall corresponding to each distance between the corner posts.

At least some of the wall panels may be able to overlap one another in the direction lengthwise of the head and base members, to accommodate changes in the distance between the upwardly extending edges of the panels which are remote from one another.

Each wall panel may comprise spaced elements of timber which are upright in use, extending between the head and base members, and a board material connected to the upright elements on one side thereof to provide a wall surface between the head and base members. Preferably the board material of each panel has upper and lower edge portions which extend to cover (at least partially) corresponding side surfaces of the head and base members respectively, and are secured to the head and base members to fix the panel in position.

To provide for the adjustment of the position of adjacent wall panels relative to one another in the direction lengthwise of the head and base members, a panel may include a board portion which extends beyond an upright element at an upright edge of the panel, so that it can overlap with the upright edge of the board portion of an adjacent panel, which is disposed to the opposite side of the head and base members to the board material of the first-mentioned panel.

Each head member may comprise an I-beam, with timber chords and a web, oriented with its chords spaced vertically above one another and its web extending substantially vertically therebetween.

The lower chord of such a head member may be arranged to form a lintel where door or window openings are to be provided in the wall. The corner posts may have portions arranged to support the lower chord of the I-beam at a suitable height for this purpose.

Each head member may comprise two of the I-beams disposed one on top the other in the same orientation as one another. The upper I-beam may provide support for an elongate base member and corner posts to form another storey above the first-erected storey of the building, and for joists for a floor of the upper storey.

Each wall panel may comprise an insulation material, preferably provided on a side of the board material to lie between the upright elements of the panel.

Such an insulation material may comprise, for example, an expanded polyurethane type of material, of a suitable thickness, e.g. 100 mm or greater for higher insulating qualities. A vapour barrier, e.g. a membrane of sheet plastics material, would also be incorporated where the wall panel is for an exterior wall of a building. Where adjustment of the position of adjacent panels is required, the insulation material would be removed as necessary from the board material which is required to extend beyond the edge of the adjacent panel.

In a building structure in accordance with the invention, the corner posts and head members may be dimensioned such that a predetermined maximum span of e.g. 10 metres between adjacent corner posts is acceptable. For any smaller span, the head member may be stronger than is necessary, but this is not disadvantageous since it enables a head member of cross-sectional shape and dimensions suitable for the 10 metre span to be used for all spans up to that limit. If the length of a wall between respective walls extending in different directions exceeds the limit, the same cross-sectional dimensions of head member could still be utilised but an additional upright member, analogous to a corner post, would have to be utilised between the ends of the wall to support a first head member and a further one of the required additional length. If the internal space of the building is divided by an internal wall, the additional upright member would be disposed where the internal wall is required to join the external wall. Any internal walls required in the building would be of analogous construction to the external walls utilising head and base members, and wall panels providing for length adjustment in the direction lengthwise of the internal wall, in the same manner as the panels for external walls.

The head members for a lower storey of the building, which carry the base members for a superposed storey, may be connected together to form a ceiling and floor sub-assembly for the lower and upper storeys respectively, which sub-assembly can be constructed away from the building structure and placed in situ as a unit. Similarly, at the top of the highest storey in a building, head members each comprising a single I- beam may be assembled together with a timber roof structure to form a ceiling and roof sub-assembly which can be fitted as a unit. Such sub-assemblies may be placed in position on a building by use of a crane.

In order to create a building structure in accordance with the invention, the first step, performed on site, would be to install a foundation, for example a concrete raft, of the required overall size of the building. Base members for the external and any required internal walls of the building would then be placed in position on the foundation, and corner posts and any necessary additional upright member positioned at the intersections of the respective external, and any internal, walls. They would be secured to the base members, and supported in the required upright orientation.

Head members, preferably of the configuration above set forth each comprising two I-beams disposed one above the other, would then be assembled to one another in the required positions to form a sub-assembly of the head members for all the walls of the building. Such assembly would not be carried out in situ, but rather at a convenient location near the positioned upright members, e.g. on the ground nearby. This sub-assembly is preferably also provided with joist members to provide flooring for the next storey of the building. Preferably the joists are boarded with floor boards. The entire sub-assembly of head members, joists and floor boarding can then be moved by crane to be positioned as required on the corner posts.

After the sub-assembly of head members, joists and floor boarding has been positioned, the panels forming the walls of the structure can be fitted between the head and base members. Each panel is fitted individually, with appropriate use of panels which can overlap one another as aforesaid in the case where the length of a wall does not permit the use of panels disposed end to end with one another.

Prior to being lifted into position, the sub-assembly of head members and joists for the ceiling structure of the lower storey and floor structure of the upper one may be provided with hand rails so that construction personnel can work on the erection of the structure for the upper storey from the floor structure thereof without requiring any external scaffolding or other safety systems. The hand rails may be secured to the respective head members, to remain in position until their removal is necessitated by the construction of external walls, e.g. of brick outside the timber-framed structure.

Internally of the timber-framed structure, plasterboard would be fitted to the inside surface of the timber frame panels, and to the ceiling beneath the joists of the assembly of head members.

The construction of the next storey of the building would then be commenced by the positioning of corner posts at the intersections between respective external and internal walls of that storey, such corner posts being secured and supported in the upright position relative to the base members fitted to the sub- assembly of head members at the top of the lowermost storey. A sub-assembly of head members for the upper storey would, if this is the uppermost storey, be constructed with a roof truss structure which can be moved into place by a crane. The fitting of wall panels to the walls of this upper storey can, on the inside of the timber framed structure, be carried out from the floor which has been fitted with the head members to the tops of the corner posts of the lower storey, while panels fitted in the exterior of the timber framed construction can be fitted from the scaffolding erected as aforesaid.

Plasterboard to provide the finish of the walls of the upper storey, and for the ceiling thereof, can be fitted to the timber framed structure and to the roof truss structure by standing on the floor of the upper storey, i.e. no scaffolding nor fall-protection systems are required in the interior of the building.

Thus far, if hand rails have been utilised as aforesaid, the erection of the structure has been carried out without requiring the use of scaffolding. Suitable scaffolding would then be erected around the timber-framed structure to enable external walls of bricks, for example, to be built up outside the timber framed structure.

The scaffolding would be raised in height as necessary as the construction of the external walls proceeds.

The invention also provides a method of constructing a timber frame structure for a building utilising the elements of the first aspect of the invention as above described.

The use of a timber frame structure according to the invention, as above described, enables a timber-framed building to be erected extremely rapidly compared with timber-framed building structures and techniques known hitherto. For example, it is estimated that the entire timber frame structure for a relatively small building, e.g. a house with a floor area of about 1000 sq ft, could be erected in a single working day. Since the timber frame structure can be erected as above-described without the use of scaffolding, the time for which scaffolding has to be on site and erected is substantially reduced. Also, there is no requirement for dismantling or partial dismantling of erected scaffolding and re-erecting thereof in a different configuration between the stages of building the timber frame structure and building external walls of brick. Scaffolding might be required to be in use for only, approximately, half the length of time it has been necessary for previously-known timber-framed constructional techniques.

The invention will now be described by way of example only with reference to the accompanying drawings, of which: Figure 1 is a perspective view of an embodiment of timber framed structure, in accordance with the invention; Figure 2 is a perspective view of elements of the lower storey of the structure; Figure 3 is a perspective view of a corner post of the structure; Figures 4, 5 and 6 are perspective views of wall panels for use in the structure; Figures 7, 8 and 9 are perspective views illustrating the disposition of wall panels in relation to one another in a structure; Figures 10 and 11 are perspective views and elements and assemblies of the building structure in accordance with the invention.

Referring firstly to Figures 1 and 2 of the drawings, this shows a timber-framed building structure in accordance with the invention. The structure is for a building (e.g. a house) having two storeys, namely a lower storey 10 and an upper storey 12, surmounted by a pitched roof structure 14. Corner posts for the lower storey 10 are visible at 16, 18 respectively, and for the upper storey at 20, 22. A head member for the visible wall of the lower storey 10 is indicated at 24, which is incorporated as described hereafter in an assembly which also forms the floor of the upper storey 12. A head member for the visible wall of the upper storey is indicated generally at 26, and this head member supports the roof structure 14. The entire structure is constructed on a foundation 30 such as a concrete raft, and on this foundation are supported elongate base members upon which the walls of the structure are carried and accordingly which extend along the lines of such walls. Two adjacent such base members, meeting at the corner post 16, are visible at 32, 34 respectively.

Figure 2 of the drawings shows one of the corner posts 16 or 18 of the lower storey 10. The corner post 16 is shown in greater detail in Figure 3. It comprises two generally U-shaped members 36, 38 disposed at right angles to one another, the member 36 comprising two spaced parallel upright timber elements 40, 42 joined by a board element 44, e.g. of plywood, which extends above the upper ends of the members 40, 42 and a small distance below the lower ends thereof. Similarly the member 38 comprises timber elements 46, 48 and a board element 50, e.g. of plywood connecting the timber elements 46, 48 and also extending above the level of the upper ends of such elements and a small distance below the level of the lower ends of such elements.

Further timber members 52, 54 are disposed to occupy the right-angled corner between the members 42, 46, and suitable fastening elements secure these components together as illustrated.

In Figure 2, it will be seen that the bottom ends of the timber members 40, 42 rest on the base member 34, and the bottom ends of the timber members 46, 48 likewise rest on the base member 32. The lowermost edges of the board elements extend down to the top surface of the foundation 30.

The tops of the corner posts at the intersections of the walls of the building are joined by respective head members. As seen in Figure 1, the tops of the corner posts 16, 18 are joined by a head member comprising an I-beam 60 above which is a further I-beam 62. The lower I-beam 60 is seen in isolation in Figure 7 of the drawings, and it will be noted that it comprises upper and lower chords 64, 66 extending parallel to one another and secured together in such relationship by an upright web 68 extending there between. The upper I-beam 62 is of the same configuration, its lower chord being connected to the upper chord 64 of the I-beam 60. The assembly of I-beams 60, 62 is used in providing an assembly which forms the basis for the ceiling of the room or rooms forming the lower storey 10 and the floor for the upper storey 12. The lower I-beam 60 is supported on the uppermost ends of the upright members 40, 42, 46, 48 and 52, 54, of each of the corner posts.

The timber frame structure further comprises wall panels which fit between the base member and head member of each respective wall of the structure. In Figure 1 the visible wall of the lower storey of the building has a number of wall panels indicated at 70, 72, 74, 76, 78, 80 and 82. These panels are selected ones of a number of standard panels.

Firstly, the panels 70, 72, 74, 76 and 78 are each as shown in Figure 6. This comprises a board 90 of plywood, to which are secured three spaced parallel upright timber stud elements 92, 94, 96. The board 90 extends above the level of the stud elements and below the bottoms thereof, in the same manner as the board elements 44, 50 of the corner post shown in Figure 3. A further type of wall panel is shown in Figure 5, which comprises a board element 98 and two stud elements 100, 102. This panel, used as the panel 82 in the wall shown in Figure 1, is as the panel of Figure 6 but of only half the width thereof.

Yet a further panel is shown in Figure 4. This is as the panel of Figure 6, having a board member 104 of the same dimensions but with only two stud elements 106, 108 of which the later is disposed centrally of the board member and the former at one edge. The stud element 106 could be disposed at the opposite edge of the board member 104 so as effectively to make a left-handed or a right-handed panel according to the edge at which it is disposed.

A panel with the stud element 106 at the opposite edge to that where it is shown in Figure 4 is used as the panel 76 in the wall visible in Figure 1.

Finally, the panel 80 in Figure 1 is as the panel 6 but is cut off at a suitable height above its lowermost end to provide an opening above it for installation of a window.

Although not shown in the illustration, each of the panels above described would also incorporate thermal insulation, e.g. of plastics material such as polyurethane foam, occupying the space between the stud elements of the panel. A vapour barrier, e.g. a plastics membrane, would also be included so that the wall has, in addition to the required thermal insulation, appropriate resistance to passage of water vapour across the wall.

Figures 7, 8 and 9 illustrate the manner in which, in the erected timber frame structure, the wall panels as above described fit in relation to the base and head members 34 to form the walls. Figure 7 shows a panel as shown in Figure 6, with its stud elements 92, 94, 96 extending between the base member 34 and the lowermost chord of head member 60. The board 90 of the panel, where it extends below the lower ends of the stud elements, lies against the side face of the base member 34 while where the board extends above the upper ends of the stud elements it lies against the side of the lower chord 66 and up to the upper chord 64.

Figure 7 shows another panel which is of a type shown in Figure 4, arranged with its board (104) on the opposite side of the base member and the head member to the board 90 of the first panel. Because there is no stud element at the visible upright edge of the board 104, the board 104 is able to overlap the first panel in the direction lengthwise of the base element and head member, up to the point at which the stud element midway between the upright edges of the panel abuts the stud element 96 of the first panel, thereby allowing some adjustment in the total distance between the upright edges of the two illustrated panel.

Referring now to Figures 8 and 9 of the drawings, these show diagrammatically, a base member 34, a head member 60, a panel as shown in Figure 6 whose board is illustrated at 90, and a panel as shown in Figure 4 (but of opposite hand) whose board is indicated at 104 and stud elements at 106, 108. In figure 9, the panel 104, 106, 108 has been slid towards the first panel until it overlaps therewith to virtually the full extent of the board 104 which extends beyond the stud element 108. To enable this to be done, of course, an appropriate amount of insulation has to be removed from the board 104 (although it will be appreciated that no insulation is shown in these figures in any event).

In Figure 1, a space is shown between panels 76, 78. This space may be dimensioned to fit the fixed peripheral frame of a door. Suitable adjustment between the relative positions of panels 74, 76, in the manner shown in Figures 8 and 9, enables the space between the panels 76, 78 to be adjusted to match the width of the door frame.

Hence, whatever is the length of a wall of a timber frame structure, and whatever windows and doors might be included in it, it can be constructed by using a small number of "standard" panels. The head member extends between corner posts at the end of the wall, and provides the lintel above each door and window opening.

Internally of the building, the walls would be finished by the application thereto of plasterboard sheets which can then be plastered, as is done for known timber-framed building structures. Where, on the interior surface of the timber-framed structure, one or more stud elements of wall panels are presented without a covering board, a timber filling element of thickness corresponding to the ply-wood boards of the wall panels has to be secured to each stud element so as to present a surface co-planar with the surface of the ply-wood boards to which the plasterboard can be fixed.

The dimensions of a head member 60, 62 are selected so as to provide adequate structural strength for a wall up to a predetermined length, e.g. 10 metres between corner posts. If a building has a wall longer than this, an additional supporting post or posts may be provided between the corner posts at the ends of the wall, and an additional head member or members of suitable length used. Where a building has one or more structural internal walls, a supporting post analogous to a corner post would be provided where an internal structural wall intersects the external wall of the structure.

Referring now to Figure 10 of the drawings, this shows the lower storey of the timber frame structure, with one wall thereof being seen in detail with a head member comprising two I-beams 120, 122 supported on the ends of the upright members of corner posts at the ends of the wall, and with wall panels in position to provide the timber wall structure with suitable openings for a window and a door. As above described, the lower I-beam 120 of the head member forms the lintels above the doors and window openings. The upper I-beams on opposite sides of the structure have a plurality of spaced parallel joist members as indicated at 124 extending between them to provide a support for floor boarding for the upper storey of the building and to provide for attachment of plasterboard to form a ceiling of the lower storey. The joists 124 may be secured to the opposite I-beams by conventional joist hangers.

Figure 10 also shows that the upper I-beam 122 has secured to the upwardly-facing surface of its upper chord a timber member 126 which forms a base member for the support of corner posts for the upper storey of the structure and for panels to form the wall of that structure. The panels used for the upper storey are the same as for those used for the lower storey, and they are assembled in the same manner as for the lower storey in relation to the base members, corner posts, and head members to form the upper storey. Further storeys of the same configuration could be provided, up to, perhaps, six storeys.

Figure 11 shows a roof truss assembly for the structure, It includes two I-beams 130, 132 which form the head members extending between respective corner posts on opposite sides of the structure. These I-beams are identical to the I-beams 60, 62 and the other I-beams used in the head members of the structure. The beams 130, 132 are joined by a number of spaced parallel joists 134 whose ends are secured to the upper chords of the respective I-beams. The roof structure further comprises rafters 136 and upright and inclined braces 138, 140, all arranged in known manner for such roof structures. In installation of the roof structure, as a final or near-final stage of the erection of the timber frame structure as above described, the structure shown in Figure 11 would be constructed on site at ground level from the respective components as above described. The head members in the form of I-beams 130, 132 for the one pair of opposite walls of the building structure would be assembled with the roof as shown in Figure 11, while the head members of the other pair of opposite walls of the structure would be fitted to the tops of the respective corner posts.

The complete roof assembly, as shown in Figure 11, would then be lifted by crane to be fitted on top of the previously-erected roofless structure.

To construct a timber-framed building structure in accordance with the invention, the first stage to be conducted on site is the preparation of a foundation, e.g. a concrete raft, upon which the base members for the walls of the lower storey would be installed. The corner posts would be connected to the base members where the external walls (and any internal walls) meet, and temporarily supported in an upright orientation.

A structure forming the head members to be supported on the corner posts of the lower storey would be constructed on site at ground level, including the joists which carry the floor of the upper storey and ceiling of the lower storey, and lifted by crane to be positioned as shown in Figure 10, this structure including the base members for the walls of the upper storey. It is then possible to install the panels forming the walls of the lower storey, extending between the base members and head members thereof. Construction of the upper storey including its corner posts, roof structure as above described, and finally panels forming the walls of the upper storey can then be undertaken.

Scaffolding can then be erected for use in building cladding walls, e.g. of brick, roofing, and other external operations at high level. It will be appreciated that such scaffolding is required for much less time than it has to be in place for previously-known timber framed buildings.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims (25)

1. Claims 1. A timber frame structure for a building, comprising: elongate base members extending along lines of respective walls of the building; corner posts extending upwardly from the base members at intersections of respective walls; elongate head members extending between the corner posts at upper end parts thereof; and a plurality of wall panels extending between the head and base members to provide walls for the structure.
2. 2. A structure according to claim 1 wherein the wall panels comprise selected ones from a number of standard panels.
3. 3. A structure according to claim 2 wherein at least some of the wall panels are able to overlap one another in the direction lengthwise of the head and base members, to accommodate changes in the distance between upwardly extending edges of the panels which are remote from one another.
4. 4. A structure according to any one of the preceding claims wherein each wall panel comprises spaced elements of timber which are upright in use and which extend between the head and base members, and a board material connected to the upright members on one side thereof to provide a wall surface between the head and base members.
5. 5. A structure according to claim 4 wherein the board material has upper and lower portions which extend to cover, at least partially, corresponding side surfaces of the head and base members respectively.
6. 6. A structure according to claim 5 wherein the upper and lower portions of board material are secured to the head and base members to fix the panel in position.
7. 7. A structure according to claim 3, or any of claims 4, 5 and 6 as appendent thereto, wherein a panel includes a board portion which extends beyond an upright element of the panel, for overlapping with the upright edge of an adjacent panel disposed with its board material on the opposite side of the head and base members.
8. 8. A structure according to any one of the preceding claims wherein each head member comprises an I-beam, oriented with its chords spaced vertically above one another and its web extending substantially vertically therebetween.
9. 9. A structure according to claim 8 wherein the lower chord of the head member forms a lintel where door or window openings are provided in the wall.
10. 10. A structure according to claim 9 wherein the corner posts have portions arranged to support the lower chord of the I-beam.
11. 11. A structure according to any of claims 8 to 10 wherein a head member comprises two said I-beams disposed one on top of the other in the same orientation as one another.
12. 12. A structure according to claim 11 wherein the upper I-beam supports an elongate base member and corner posts to form another storey above a lower storey.
13. 13. A structure according to any one of the preceding claims wherein each waIl panel comprises an insulation material.
14. 14. A structure according to claim 13 as appendent directly or indirectly to claim 4 wherein the insulation material is disposed on a side of the board material, to lie between the upright elements of the panel.
15. 15. A structure according to any preceding claim further comprising one or more additional upright members provided between corner posts of a wall.
16. 16. A structure according to claim 15 wherein an additional upright member is provided where an internal wall of the building joins an external wall.
17. 17. A structure according to any one of the preceding claims wherein head members for a lower storey of the building, which carry base members for a superposed storey, are connected together to form a ceiling and floor assembly for the lower and upper storeys.
18. 18. A structure according to claim 17 wherein the ceiling and floor assembly is placed in situ as a pre-assembled unit.
19. 19. A structure according to any one of the preceding claims wherein, at the upper end of the highest storey of a building, head members therefor are assembled with a timber roof structure to form a roof assembly placed in situ as a unit.
20. 20. A method of constructing a timber frame structure for a building, comprising: providing elongate base members along the lines of walls of the building; providing corner posts extending upwardly from the base members at intersections of the respective walls; providing elongate head members extending between the corner posts at upper end parts thereof, above the base members; and providing a plurality of wall panels extending between the head and base members to form walls for the structure.
21. 21. A method according to claim 20 further comprising adjusting adjacent wall panels in respect of the distance by which they overlap one another in the direction lengthwise of the head and base members, to provide a required length in said direction between edges of the panels which are remote from one another.
22. 22. A method according to claim 20 or claim 21 comprising assembling head members for a storey of the building into a unit which forms at least part of a ceiling structure for that storey and a floor structure for a further superposed storey, and fitting the assembly to the corner posts of the first said storey as a unit.
23. 23. A timber frame structure for a building substantially as hereinbefore described with reference to and/or as shown in the accompanying drawings.
24. 24. A method of constructing a timber frame structure for a building substantially as hereinbefore described.
25. 25. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.

    25. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.

    Claims 1. A timber frame structure for a building, comprising: elongate base members extending along lines of respective walls of the building; corner posts extending upwardly from the base members at intersections of respective walls; elongate head members extending between the corner posts at upper end parts thereof; and a plurality of wall panels extending between the head and base members to provide walls for the structure.

    2. A structure according to claim 1 wherein the wall panels comprise selected ones from a number of standard panels.

    3. A structure according to claim 2 wherein at least some of the wall panels are able to overlap one another in the direction lengthwise of the head and base members, to accommodate changes in the distance between upwardly extending edges of the panels which are remote from one another.

    4. A structure according to any one of the preceding claims wherein each wall panel comprises spaced elements of timber which are upright in use and which extend between the head and base members, and a board material connected to the upright members on one side thereof to provide a wall surface between the head and base members.

    5. A structure according to claim 4 wherein the board material has upper and lower portions which extend to cover, at least partially, corresponding side surfaces of the head and base members respectively.

    6. A structure according to claim 5 wherein the upper and lower portions of board material are secured to the head and base members to fix the panel in position.

    7. A structure according to claim 3, or any of claims 4, 5 and 6 as appendent thereto, wherein a panel includes a board portion which extends beyond an upright element of the panel, for overlapping with the upright edge of an adjacent panel disposed with its board material on the opposite side of the head and base members.

    8. A structure according to any one of the preceding claims wherein each head member comprises an I-beam, oriented with its chords spaced vertically above one another and its web extending substantially vertically therebetween.

    9. A structure according to claim 8 wherein the lower chord of the head member forms a lintel where door or window openings are provided in the wall.

    10. A structure according to claim 9 wherein the corner posts have portions arranged to support the lower chord of the I-beam.

    11. A structure according to any of claims 8 to 10 wherein a head member comprises two said I-beams disposed one on top of the other in the same orientation as one another.

    12. A structure according to claim 11 wherein the upper I-beam supports an elongate base member and corner posts to form another storey above a lower storey.

    13. A structure according to any one of the preceding claims wherein each waIl panel comprises an insulation material.

    14. A structure according to claim 13 as appendent directly or indirectly to claim 4 wherein the insulation material is disposed on a side of the board material, to lie between the upright elements of the panel.

    15. A structure according to any preceding claim further comprising one or more additional upright members provided between corner posts of a wall.

    16. A structure according to claim 15 wherein an additional upright member is provided where an internal wall of the building joins an external wall.

    17. A structure according to any one of the preceding claims wherein head members for a lower storey of the building, which carry base members for a superposed storey, are connected together to form a ceiling and floor assembly for the lower and upper storeys.

    18. A structure according to claim 17 wherein the ceiling and floor assembly is placed in situ as a pre-assembled unit.

    19. A structure according to any one of the preceding claims wherein, at the upper end of the highest storey of a building, head members therefor are assembled with a timber roof structure to form a roof assembly placed in situ as a unit.

    20. A method of constructing a timber frame structure for a building, comprising: providing elongate base members along the lines of walls of the building; providing corner posts extending upwardly from the base members at intersections of the respective walls; providing elongate head members extending between the corner posts at upper end parts thereof, above the base members; and providing a plurality of wall panels extending between the head and base members to form walls for the structure.

    21. A method according to claim 20 further comprising adjusting adjacent wall panels in respect of the distance by which they overlap one another in the direction lengthwise of the head and base members, to provide a required length in said direction between edges of the panels which are remote from one another.

    22. A method according to claim 20 or claim 21 comprising assembling head members for a storey of the building into a unit which forms at least part of a ceiling structure for that storey and a floor structure for a further superposed storey, and fitting the assembly to the corner posts of the first said storey as a unit.

    23. A timber frame structure for a building substantially as hereinbefore described with reference to and/or as shown in the accompanying drawings.

    24. A method of constructing a timber frame structure for a building substantially as hereinbefore described.