GB2465365A

GB2465365A - Method and apparatus for constructing timber-framed buildings

Info

Publication number: GB2465365A
Application number: GB0820795A
Authority: GB
Inventors: Colin Michael Oakley
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-11-13
Filing date: 2008-11-13
Publication date: 2010-05-19
Also published as: GB0820795D0

Abstract

The invention relates to a method for constructing a timber-framed building comprising the steps of erecting a wall structure of a lower storey (12 figure 1) of the building, constructing a floor assembly, and assembling a roof truss assembly (18 figure 1) on top of the floor assembly. The roof truss (18 figure 1) is releasably connected to the floor assembly using a releasable connecting means 60 and placing the connected floor and roof assembly on top of the wall structure of the lower storey (12 figure 1). The roof truss assembly (18 figure 1) is then disconnected from the floor assembly and the roof truss is removed from the floor assembly. A wall structure is then constructed on an upper storey (16 figure 1) on top of the floor assembly, and the roof truss assembly (18 figure 1) is placed on top of the wall structure of the upper storey (16 figure 1). A later embodiment relates to a releasable connecting means 60 for connecting a roof truss assembly (18 figure 1) to a floor assembly.

Description

Title: Method for Constructing Timber-Framed Building Structures, and Apparatus to Facilitate Same

Description of Invention

The present invention relates to a method for constructing a timber-framed building, and securement / safety apparatus to facilitate the construction of a timber-framed building by the method.

Timber-framed construction is well known for use in relatively small buildings such as houses, and has many advantages over traditional construction techniques wherein bricks or blocks are used to construct load-bearing walls.

Not least of these advantages is the relatively light weight of timber frames, and the fact that parts of the frame can be pre-fabricated rather than having to be constructed on site, which allows houses to be built relatively cheaply and quickly.

Typically, once the foundation has been established, the construction of a timber-framed house requires scaffolding to be erected which must remain in situ for the duration of the construction. The scaffolding is not only required for IS..

the construction of the walls and roof, but also for the installation of high-level external fittings such as guttering and downpipes. Additionally, the use of : 25 scaffolding requires fall-arrest systems, such as airbags, to be used in order to prevent workmen suffering injuries through falls from upper storeys. The provision of scaffolding for extended periods of time, and the provision of the 5....

* necessary safety apparatus to be used in conjunction with the scaffolding, can be expensive.

It is broadly the object of the present invention to solve or reduce one or more of these problems.

According to one aspect of the invention we provide a method for constructing a timber-framed building including the steps of: erecting a wall structure of a lower storey of the building; constructing a floor assembly, and assembling a roof truss assembly on top of the floor assembly; releasably connecting the roof truss assembly to the floor assembly using releasable connecting means; placing the connected floor and roof assembly on top of the wall structure of the lower storey; disconnecting the roof truss assembly from the floor assembly and removing the roof truss assembly from the floor assembly; constructing a wall structure of an upper storey on top of the floor assembly; and placing the roof truss assembly on top of the wall structure of the upper storey.

The method may further include constructing the floor assembly and roof truss assembly at ground level, adjacent the wall structure of the lower storey of the building. * **

Preferably the releasable connecting means comprises a number of connecting assemblies, each comprising a connecting member and a receiving member with which the connecting member is releasably engageable; the connecting member being provided on one of the roof truss assembly and the floor assembly and the receiving member on the other S...

thereof, the connecting member and receiving member engaging and disengaging with one another by relative vertical movement between the roof truss assembly and the floor assembly.

Preferably the method further includes providing a guard structure on a part of the releasable connecting means engaging the floor assembly. The method may include displacing the guard structure relative to the connecting assemblies of the releasable connecting means, between a first position in which the guard structure is positioned relative to the or each connecting assembly so as to enable the roof structure to be connected and disconnected from the floor assembly, and a second position in which it is effective to guard against falls from the upper storey. Displacing the guard structure relative to the or each connecting assembly may comprise pivoting the guard structure between the first position and second position.

The method may include storing the materials for use in the construction of the wall structure of the upper storey on the floor assembly prior to assembling the roof truss structure on top of the floor assembly, so that when the roof truss structure is disconnected from the floor assembly, the materials are disposed on the upper storey for use in the construction of the wall structure.

1 5 The method may further include providing a plurality of spaced parallel joist members between opposite beams of the upper beam assembly, and laying a floor over the joists, during the construction of the floor assembly.

According to a second aspect of the invention, we provide a releasable connecting means for connecting a roof truss assembly to a floor assembly, S..... including a number of connecting assemblies, each of which comprises a connecting member and a receiving member, each connectable to the roof *.*...

* truss assembly and floor assembly respectively. * .

Preferably the receiving member has an opening within it, with which at least a part of the connection member is engageable, and the or each connecting assembly further includes a fastening means for holding the connection member in engagement with the receiving member.

Preferably the releasable connecting means may further include a guard structure which is provided on a part of the releasable connecting means engaging the floor assembly. The guard structure may include two legs, each leg being connected to a respective receiving member. The guard structure may be is displaceable relative to the connecting assemblies, between a first position in which the guard structure is positioned relative to the or each connecting assembly so as to enable the roof structure to be connected and disconnected from the floor assembly, and a second position in which it is effective to guard against falls from the upper storey. Displacing the guard structure relative to the or each connecting assembly may comprise pivoting the guard structure between the first position and second position. The guard structure may be a handrail assembly which may be extendable lengthwise (e.g. telescopically).

According to a further aspect of the invention, we provide a roof truss assembly disposed on top of a floor assembly, releasably connected to one another by releasable connection means according to the second aspect of the invention.

The invention will now be described by way of examp'e on'y with reference to the accompanying drawings, of which: * ** Figure 1 is a front view of receiving members and attached guard structure **..

shown in connection with a timber-framed building construction; Figure 2 is a perspective view of a releasable connecting means shown in * connection with a floor/roof assembly; * S.. 50 Figure 3 is a perspective view of a first storey of a building construction having ** 25 an attached floor assembly, with attached receiving members and guard structures, and a roof truss assembly having attached connecting members.

Referring first to figure 1, this shows a timber-framed building structure 10 of the type that may be erected using the method and apparatus in accordance with the invention. The structure comprises a lower storey 14 and an upper storey 16, on top of which is disposed a roof truss assembly 18.

The lower storey 14 is constructed on a foundation 12 such as a concrete raft.

Elongate base members are disposed on top of the foundation 12, extending along the lines of the walls of the structure and upon which the walls of the structure are carried. Corner posts 26 are located at junctions of base members, providing a support between the base members and a lower beam assembly 20, comprising wooden beams with an I-shaped cross-section, which lies generally parallel to the base members along the lines of the walls.

A wall structure is erected on the base members and extends up to the lower beam assembly 20, the wall structure including panels 28 formed from boards of plywood, which are secured to spaced upright timber elements. Panels 28 may be cut off at a suitable height to provide an opening for installation of a window, and a space may be left between panels 28 to allow for installation of a doorframe. The lower beam assembly 20 forms the lintels above doors and window openings.

The upper storey 16 includes a floor structure at its base which includes an upper beam assembly 22 which is connected to and lies above the lower beam assembly 20 of the lower storey 14. The beams comprising the upper 20 beam assembly 22 on opposite sides of the structure have a plurality of * *** spaced parallel joist members 30 extending between them (which may be connected by conventional joist-hangers) which provide a support for the floor **** 0s * of the upper storey 16, and to provide a surface onto which plasterboard may S....

be attached to form a ceiling of the lower storey. **5*

Base members are positioned on the upper beam assembly 22 to form a base for the wall structure of the upper storey 16, in a similar way to that disposed on the foundation 12 for the lower storey 14. A wall structure is erected in the same manner as for the lower storey 14, in relation to the base members, corner posts 26, and beams 24 which form part of the roof truss assembly 18, to form the upper storey 16.

The roof truss assembly 18 includes two beams lying parallel one another which extend between respective corner posts 36 of the upper storey of the structure. The beams 24 are joined by a plurality of joists 46 which are secured to the top surface of the beams, running parallel one another between the two beams. Rafters 40 extend upwards from either side of the structure, spaced from one another along the length of the beams 24 so as to align with the joists 46, held in connection with the joists 46 on either side of the structure, and defining a ridge 48 over the centre of the roof truss assembly 18. The lower ends 40a of the rafters 40 overhang the beams 24 downwardly and outwardly so as to form the eves of the roof structure. The roof truss assembly 18 further includes upright 42 and inclined 44 braces, arranged in a known manner for such roof structures.

Releasable connecting means 60 are used to secure the lower 20 and upper 22 beam assemblies to the roof truss assembly 18 during construction. The releasable connecting means 60 includes a number of connecting assemblies, each comprising a receiving member 52 and a connecting member 54. Each receiving member is connected to a guard structure, which is a handrail in this case, and shall hereafter be referred to as a handrail assembly. * .e

* I. * *" 20 *.** Each receiving member 52 is generally box-shaped, having a flat rectangular front face 74 upon which brackets 70 are provided, holding a pin to provide a pivotable connection between the respective receiving member 52 and a respective first end 72a of a leg 72 of a handrail assembly 50. The receiving member 52 has an aperture inset from each corner of its face, so that the receiving member 52 can be attached to the connected upper 22 and lower 20 beam assemblies by way of fastening means (such as bolts). A further aperture 68 is disposed towards the bottom of the face 74 of the receiving member 52, and extends through the receiving member to allow insertion of a bolt.

For each receiving member 52 there is provided a connecting member 54, which is a generally rectangular plate, having a first aperture 64, a second aperture 62 and a third aperture 58 provided centrally across its width and spaced along its length, the first aperture 64 being in close proximity to a first end 54a of the connecting member 54 and the third aperture 58 being in close proximity to a second end 54b. The connecting member 54 is attached to one of the beams 24 of the roof truss assembly 18 by way of a bolt which is inserted through the second (central) aperture 62 of the connecting member 54. When in connection with a beam 24 of the roof truss 18, the first end 54a of the connecting member 54 protrudes above the truss, so that the aperture 64 is unblocked by the beam.

Each receiving member 52 further includes an opening 76 extending downwardly through it from an elongate slot in its upper surface, for receiving the second end 54b of a connecting member 54. The location of the aperture 68 in the face of the receiving member 52 is such that when the connecting member 54 has been inserted to its full extent, the aperture 68 in the receiving member 52 aligns with the third aperture 58 in the connecting member so as to receive fastening means in the form of a bolt to hold the receiving member 52 * *S relative to the connecting member 54. S... * . * I.

The handrail assembly 50 includes a pair of legs 72, a first end 72a of each of *5***S * : which is pivotably connected to the respective front face 74 of a receiving S.....

member 52, by the brackets 70 and pin held thereby. The second end 72b of each leg 72 is connected to the upper rail 68a of a pair of elongate rails 68, which extend parallel one another in a direction transverse to the alignment of the legs 72 so as to be in parallel alignment with the surface of the beams 20, 22 to which the receiving members 52 are connected. The elongate rails 68 are hollow, and inside each is connected a generally C-shaped end rail 66.

Each end rail 66 has a smaller cross-section than the elongate rails 68, and has two elongate portions 65 which extend parallel to one another and perpendicular to a straight back section 67. The elongate portions 65 of the end rails engage with the hollow elongate rails 68, such that they are slidably connected to the elongate rails 68, allowing the rail to be extended at both ends. To prevent the end rails 66 from disconnecting from the elongate rails 68, stop formations are provided.

The handrail assembly 50 is pivotably moveable between a first position, in which the legs 72 of the handrail assembly define an angle of roughly sixty degrees with the plane of the surface of the beams 20, 22 to which the receiving members 52 are connected, and a second position wherein the legs 72 are in an upright orientation.

To provide for the pivotal movement of the handrail assembly 50, an aperture is provided adjacent the first end 72a of each leg 72 of the handrail assembly 50, extending across its width, the aperture being elongated in the direction lengthwise of the leg 72, and engaged by the pin held by the brackets 70 on *. the face of the receiving member 52. As the handrail assembly 50 is moved from the first position to reach the second position, the first end 72a of each leg is allowed to drop, as the leg is allowed to move downward relative to the S.....

* : 20 position of the pin within the aperture. The leg 72 can move no further

SS

* downward once the pin meets the top of the aperture in the leg, and as the wall of the leg 72 lies adjacent the face 74 of the receiving member 52, the **.

handrail assembly 50 cannot pivot about the pin. In order to release the handrail assembly 50 so that it can be moved back to its first position, the legs 72 must be lifted so that the pin lies against the lower end of the elongate aperture, so that the wall of the leg no longer lies adjacent the face 74 of the receiving member 52. It is then possible to move the leg 72 pivotably back to the first position.

A timber frame building 10 as shown in figure 1 may be constructed by the method described hereafter, which involves a substantially reduced use of scaffolding, compared with previously-known construction methods, and requires land not much greater in size than twice the footprint of the building itself.

First a concrete raft or other foundation 12 is laid on the site where the building is to be erected. Base members for the lower storey 14 are laid on top of this foundation 12, extending along the lines of the external walls between the corners of the building. Corner posts 26 are erected where the base members meet one another. A wall structure is erected along the lines of the base members by connecting panels 28 to the base members and holding them in an upright position using temporary braces.

Once the lower storey 14 of the building has been constructed, the beams and other components used in the construction of the upper storey 16 of the building, and the roof truss assembly 18, are assembled on the ground next to the partly constructed building. This assembly of beams and roof truss assembly 18 shall be referred to as the connected floor and roof assembly. * S ****

The connected floor and roof assembly includes the lower beam assembly 20, S.....

* 20 which is an arrangement of beams matching the layout of the base members * laid on the foundations 12 of the building, so that each beam has the same length and relative position as a corresponding base member of the lower 0*** storey 14. The beams are connected to one another so that they form an outline of the perimeter of the building structure.

On top of the lower beam assembly 20 lies an upper beam assembly 22, each beam in the upper beam assembly 22 having a corresponding beam in the lower beam assembly 20 (in terms of length) to which it is secured, so that the upper beam assembly 22 matches the lower beam assembly 20 and is connected to it so as to lie directly above it, forming what shall be referred to as the floor assembly. A plurality of spaced parallel joist members 30 is connected between opposite upper beams, which provides a support for the floor surface of the upper storey 16.

Flooring boards or panels are now laid over the joist members 30. A cover is placed over the stair well, i.e. the opening where the stairway of the building will open onto the floor of the upper storey, so the floor is uninterrupted. The arrangement of connected upper 22 and lower 20 beam assemblies, complete with its flooring, shall be referred to as the floor assembly. Once the floor has been laid, the panels 38 which will make up the wall structure of the upper storey are laid over the flooring, so that they will be available when it is necessary for them to be fitted.

A roof truss assembly 18 is constructed on top of the floor assembly, as hereinbefore described, so that the two main beams 24 of the roof truss assembly 18 are disposed above the equivalent beams of the upper beam structure 22, to align the length of the roof with the wall structure running the length of the building structure as required. The roof truss assembly 18 further includes rafters 40, joists 46 and support braces 42, 44 as described above. S...

*.**.. . * 20 Pairs of connecting assemblies are used to secure the floor structure and roof *.**** * * truss assembly 18 to one another. Each connecting assembly includes a connecting member 54, which is attached to a beam 24 of the roof truss S...

assembly 18 by the insertion of a bolt through the second aperture 62 and into a corresponding aperture in the beam. Pairs of connecting members 54 are spaced from one another so that they align with pairs of receiving members 52.

The receiving member 52 of each connecting assembly is attached to the upper 22 and lower 20 beam assemblies by way of bolts, so that the front face 74 of the receiving member 52 faces outwards from the upper 22 and lower 20 beam assemblies. The second end 54b of each connecting member 54 engages with the opening 76 extending from the upper surface of the corresponding receiving member 52 of the connecting assembly, so that the aperture 68 in each receiving member 52 aligns with the third aperture 58 of the connecting member 54. A fastening means is inserted through the apertures in order to hold the connecting members 54 in engagement with the receiving members 52, and in doing so, hold the beam 24 of the roof truss structure in attachment to the underlying upper 22 and lower 20 beam assemblies.

Once the floor and roof assembly has been connected using the connecting assemblies, the first aperture 64 in each connecting member 54 protrudes between the rafters 40 of the roof truss assembly 18, allowing it to be connected to a hook of a crane 56. Each of the connecting members 54 is connected to the crane hooks in this way, allowing the crane to lift the connecting members 54, and in doing so lift the entire floor and roof assembly.

The crane positions the floor and roof assembly over the lower storey 14 of the *. building which has been erected, and lowers the floor and roof assembly onto the walls which are supported by braces. Whilst being held in place by the * 20 crane, the lower beam assembly 20 can be connected to the corner posts 26 S.....

* of the lower storey, and the panels 28 of the lower storey wall structure can then be secured to the lower beam 20 so that the braces supporting the wall SI..

structure on the lower storey can be removed.

Having connected the floor and roof assembly to the lower storey 14 of the building, workmen are able to walk on the upper storey 16 due to the fact that the upper storey floor has already been laid out on the joists 30 connected to the upper beam assembly 22.

The bolts connecting the receiving member 52 and the connecting member 54 of each connecting assembly can be removed by being pulled inwards by workmen on the upper storey 16. This means that the roof truss assembly 18 is no longer attached to the upper 22 and lower 20 beam assemblies.

The crane lifts the roof truss assembly 18 from the top of the construction, allowing the workmen to work on the upper storey 16.

In order to meet safety requirements concerning the provision of fall prevention apparatus to allow the workmen to safely work on the upper storey 16, the handrail assemblies 50 must be moved into their second (i.e. upright) positions. This can be achieved from ground level outside the building, by using a rod of sufficient length to push the handrail assemblies 50 so that they stand upright. Once the handrail assemblies 50 reach an upright position, they are able to drop downwardly owing to the elongate configuration of the apertures in the legs, through which the pins extend.

The end rails 66 at either end of each handrail assembly 50 may then be extended so as to provide a barrier along the edges of the upper storey 16 ** where the receiving members 52 are connected. This enables the workmen to 0** arrange the panels 38 and corner posts 36 on the upper storey, as the panels * .*S..

* : 20 38 and corner posts 36 themselves were stored on the upper beam assembly * *.*** * 22 once the floor was laid prior to being lifted into position on the building structure, so there is no need for any of the parts to be lifted to the upper **.* storey 16.

The wall structure on the upper storey 16 is erected in the same manner as that on the lower storey 14.

Once the wall structure is in place on the upper storey 16, and has been secured by braces so as to hold it in position, the crane moves the roof truss assembly 18 back into position above the upper storey 16. The beams 24 of the roof truss assembly 18 can be secured to and supported by the corner posts 36, allowing the wall structure to be secured to the beams 24, and the braces to be removed.

With the roof truss assembly 18 in place and secured to the rest of the construction, the bolts holding the connecting members 54 (through their second apertures 62) to the beams 24 in the roof truss assembly 18, are pulled inward, releasing the connecting members 54 from the roof truss assembly 18. The connecting members 54 remain attached to the hook of the crane by way of their first apertures 64, and may be lifted away from the sides ofthe building.

Once the construction on the upper storey 16 has been completed, all that remains is to remove the receiving members 52 and the attached handrail assemblies 50 from the sides of the building. To do this, workmen can stand on a step placed against the sides of the building, in order to undo the connection bolts holding the receiving members 52 to the upper 22 and lower ** 20 beam assemblies. Before detaching the receiving members 52, the hooks of the crane 56 may be connected to the handrail assemblies 50 in order to lift the apparatus away to safety rather than letting it fall to the ground.

S..... * 20

It should be noted that once the floor and roof assembly has been fixed in *:** place on top of the lower storey 14, it is safe for workmen to begin work on the I...

upper storey 16 due to the fact that the upper storey has a floor in place to prevent debris falling on those working below. As soon as the roof truss assembly 18 has been fixed in position, roofing can be laid to provide cover for the upper storey, which allows work to start on the upper storey of the building.

Once the timber frame structure has been completed, scaffolding may be erected in order to apply masonry to the outside of the structure, and to erect guttering. Due to the fact that the building structure has been completed prior to the scaffolding being erected, the scaffolding is in use for a much reduced length of time in comparison with standard building techniques.

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. a.. * . a * a. * . a...

a..... * . *... a. * *.* *. a. a a.... a *

Claims

Claims 1. A method for constructing a timber-framed building including the steps of: erecting a wall structure of a lower storey of the building; constructing a floor assembly, and assembling a roof truss assembly on top of the floor assembly; releasably connecting the roof truss assemb'y to the f'oor assembly using releasable connecting means; placing the connected floor and roof assembly on top of the wall structure of the lower storey; disconnecting the roof truss assembly from the floor assembly and removing the roof truss assembly from the floor assembly; constructing a wall structure of an upper storey on top of the floor assembly; and placing the roof truss assembly on top of the wall structure of the upper storey. * .. * * * * **
2. A method according to claim 1, further including constructing the floor assembly and roof truss assembly at ground level, adjacent the wall structure * 20 of the lower storey of the building.

****** * *
3. A method according to claim 1 or claim 2, wherein the releasable I...connecting means comprises a number of connecting assemblies, each comprising a connecting member and a receiving member with which the connecting member is releasably engageable; the connecting member being provided on one of the roof truss assembly and the floor assembly and the receiving member on the other thereof, the connecting member and receiving member engaging and disengaging with one another by relative vertical movement between the roof truss assembly and the floor assembly.
4. A method according to any of the preceding claims, further including providing a guard structure on a part of the releasable connecting means engaging the floor assembly.
5. A method according to claim 4, including displacing the guard structure relative to the connecting assemblies of the releasable connecting means, between a first position in which the guard structure is positioned relative to the or each connecting assembly so as to enable the roof structure to be connected and disconnected from the floor assembly, and a second position in which it is effective to guard against falls from the upper storey.
6. A method according to claim 5, wherein displacing the guard structure relative to the or each connecting assembly comprises pivoting the guard structure between the first position and second position.
7. A method according to any of the preceding claims, further including *:..,. storing the materials for use in the construction of the wall structure of the *::::* upper storey on the floor assembly prior to assembling the roof truss structure on top of the floor assembly, so that when the roof truss structure is * 20 disconnected from the floor assembly, the materials are disposed on the upper * S....* storey for use in the construction of the wall structure. *
8. A method according to any one of the preceding claims, further including providing a plurality of spaced parallel joist members between opposite beams of the upper beam assembly, and laying a floor over the joists, during the construction of the floor assembly.
9. A releasable connecting means for connecting a roof truss assembly to a floor assembly, including a number of connecting assemblies, each of which comprises a connecting member and a receiving member, each connectable to the roof truss assembly and floor assembly respectively.
10. A releasable connecting means according to claim 9, wherein the receiving member has an opening within it, with which at least a part of the connection member is engageable, and the or each connecting assembly further includes a fastening means for holding the connection member in engagement with the receiving member.
11. A releasable connecting means according to claim 9 or claim 10, further including a guard structure which is provided on a part of the releasable connecting means engaging the floor assembly.
12. A releasable connecting means according to claim 11, wherein the guard structure includes two legs, each leg being connected to a respective receiving member.
13. A releasable connecting means according to claim 11 or claim 12, wherein the guard structure is displaceable relative to the connecting assemblies, between a first position in which the guard structure is positioned *.**. relative to the or each connecting assembly so as to enable the roof structure to be connected and disconnected from the floor assembly, and a second * S....* 20 position in which it is effective to guard against falls from the upper storey.*..... * .
14. A releasable connecting means according to claim 13 wherein displacing the guard structure relative to the or each connecting assembly comprises pivoting the guard structure between the first position and second position.
15. A releasable connecting means according to any one of claims 11 to 14, wherein the guard structure is a handrail assembly.
16. A releasable connecting means according to claim 15 wherein the handrail assembly is extendable lengthwise (e.g. telescopically).
17. A releasable connecting means substantially as hereinbefore described with reference to and / or as shown in the accompanying drawings.
18. A roof truss assembly disposed on top of a floor assembly, and releasably connected thereto by releasable connecting means according to any one of claims 9 to 17.
19. A method for constructing a timber-framed building substantially as hereinbefore described with reference to and/or as shown in the accompanying drawings.
20. Any novel feature or novel combination of features substantially as described herein and/or as shown in the accompanying drawings. * ** * * * * ** * *** * * I. ******* * * * * * I. * ** S. *5*S** S *