The present invention relates to a kit of parts for the construction of a building and a method of construction of a building using a kit of parts. Particularly, though not exclusively, the invention relates to a building system comprising precision manufactured timber parts that are transported to a building site and assembled on-site without the requirement for scaffolding.

The construction industry is a major contributor to carbon emissions. Traditional building methods and the materials utilised have a high adverse impact on the environment. Furthermore, the building process is typically slow and the environment of a building site can be hazardous due to working at height, dropped objects etc. Modular building is an alternative technique and enables the building to be constructed in modules offsite and transported to the required location where elements are craned into place and appropriately joined. Modular buildings are only suitable for approximately 10% of building sites since the site must have the space required to accommodate a crane to lift and deliver a large modular structure.

Accordingly, it is an object of the present invention to provide a building system that alleviates one or more of the aforementioned disadvantages.

According to a first aspect of the invention there is provided a kit of parts for the construction of a building comprising: building parts, including at least one ground floor element, at least one upperlevel floor element, a roof, structural columns, non-structural panels; and temporary reusable parts, including a supporting structure adapted to support at least one upper level floor element or other building part at a precise predetermined height and configured for assembly on the ground floor element(s) within a footprint of the building, such that the assembled structure is configurable to a precise predetermined height to support the upper-level floor element(s) during construction of the building.

Advantageously, the invention provides a component-based building system using a kit of parts that is manufactured offsite and constructed onsite. Furthermore, the building is erected using a temporary support structure that is adapted to be assembled within the footprint of the building enabling a new method of building construction.

The building parts may be transportable and movable using vehicle mounted lifting equipment. The building parts may be manufactured having a size and weight that enables transfer using a telehandler, a truck mounted crane arm, a hydraulic platform and the like.

The building parts may be timber based building parts. The upper-level floor element(s), the roof, structural columns and non-structural panels may comprise timber-based components.

The building parts may be at least partially constructed from raw timber, which is processed into the required form. Preferably, the building parts are precision manufactured to predetermined acceptable tolerances.

The building parts may be formed from timber to an accuracy of between +/- 2mm and +/- 8mm.The building parts may be formed from timber to an accuracy of around +/- 5mm.

Preferably, at least a portion of the building parts are formed from timber using a computerised manufacturing process in which pre-programmed software and code controls the movement of production equipment. The building parts may be formed from timber using computerised numerical control (CNC) machining.

The building parts may be stored in a controlled environment. The building parts may be maintained within a predetermined temperature and humidity range. The building parts may be maintained at a pre-set temperature and humidity. The building parts may be maintained within a humidity of between around 9 and 15%.

Thus, a large proportion of the building parts such as the upper-level floor element(s), roof, columns and panels may comprise precision manufactured timber resulting in a more ecologically sustainable building. The ground floor element(s) may comprise a number of interlocking cassettes such as those described in UK Patent Application No: 2107219.4, the entire contents of which are incorporated herein by reference. The building parts may comprise a plurality of interconnected ground floor elements. The ground floor elements may be interconnectable to form a flooring of the required shape and surface area. The ground floor element(s) may be formed from a composite material such as glass reinforced plastic.

The building parts may comprise a plurality of interconnected upper-level floor elements. The upper-level floor elements may include first floor-level elements, second- floor level elements and/or attic floor elements. The upper-level floor elements may be interconnectable to form a flooring of the required shape and surface area.

Each upper-level floor element may comprise at least one timber I-beam. Each upperlevel floor element may comprise timber I-beam(s) with upper and lower decking boards fixed thereto. The upper and/or lower decking may comprise oriented strand board.

The timber l-beam(s) may be provided to act as structural joists within the upper-level floor element(s). The timber I-beam(s) may comprise engineered timber joists conforming with the B220 engineering standard.

The at least three lengths of timber forming the structural I-beam may be precision manufactured to a tolerance of around +/- 2mm.

The building parts may comprise a plurality of roof portions interconnectable to form a roof. The roof portions may be interconnectable to form a pitched roof. The roof portions may be interconnectable to form a pitched roof with an incline of between around 15 degrees and 60 degrees. The roof portions may be interconnectable to form a pitched roof with a centrally disposed ridge line. The roof portions may be interconnectable to form a pitched roof with an asymmetric ridge line.

Alternatively, the roof portions may be interconnectable to form a substantially planar roof with an angle of incline of less than 5 degrees. The building parts may comprise a plurality of structural columns. The structural columns may be constructed to transfer load from other building parts. For example, loads from the roof and upper-level floor elements may be transferred along the structural columns and interconnected floor elements to the ground floor element.

The structural columns may comprise linear columns to bear line loads. The structural columns may comprise elongate columns to control lateral loads.

The building parts may comprise a plurality of non-structural panels. The non-structural panels may span the distance between floor elements of the building. The non- structural panels may be arranged substantially vertically between floor elements.

The building parts may further comprise connection brackets to connect the non- structural panels to the building, wherein the connection brackets are rated to support the weight of the non-structural panels. The connection brackets may be load bearing connection brackets. The connection brackets may be formed from steel. Thus, the non-structural panels may hang from the structural columns and/or the upper-level floor element(s).

The non-structural panels may include, but are not limited to: I panels, glazing panels, door panels, non-load bearing wall panels, insulation panels, cladding and the like.

The number, dimensions and relative arrangement of the building parts may be preselected to form a building with the required size and structure. The kit of parts for the construction of the building may be a parametric design such that specific input parameters and rules determine the relationship between the intended building construction and the design response.

Preferably, the reusable supporting structure comprises a braced prop structure to temporarily support the building parts during the construction of the building from the kit of parts. Thus, the supporting structure is specifically designed to support parts of the building during construction and is not designed to carry or host construction workers.

The supporting structure may be movable between an assembled configuration in which the supporting structure is arranged to structurally support elements of a building, and a transport configuration in which the supporting structure is disassembled for ease of transport.

The supporting structure may comprise a plurality of structural supports interconnectable in the assembled configuration to support the load from the upperlevel floor element(s) on the ground-floor element(s) and to support the load of the roof on the upper-level floor element(s).

The supporting structure may comprise a plurality of inter-connectable structural supports comprising load bearing leg supports, load bearing cross members and bracing members. The load bearing leg supports may be arranged for substantially vertical orientation when in the assembled configuration. The load bearing cross members may be arranged for substantially horizontal orientation when in the assembled configuration.

The support structure may comprise adjustable length structural supports. The load bearing leg supports may be adjustable to enable use of the supporting structure at different heights. The load bearing leg supports may be incrementally adjustable.

The load bearing leg supports may comprise a threaded extension member to allow incremental adjustment of the height of the supporting structure. Advantageously, incremental adjustment of the leg supports enables the accurate positioning of the supporting structure in a predetermined location and allows a gradual release of load following use as a temporary reusable part.

Alternatively, the adjustable structural supports may be telescoping.

The structural supports may be formed from aluminium. The structural supports may comprise aluminium tubing.

The supporting structure may comprise a substantially cuboid form in the assembled configuration. The supporting structure may comprise at least four load bearing leg supports and at least four load bearing cross members extending perpendicular to and between the load bearing leg supports.

The load bearing leg supports and load bearing cross member structural supports may be linked using crosswise bracing members in the assembled configuration. The structural supports may be braced using bracing members angled relative to the load bearing leg supports and load bearing cross members to form the supporting structure in the assembled configuration. Thus, the bracing members reinforce the supporting structure to support the load of the upper-level floor element(s) and/or the roof in the assembled configuration.

The supporting structure may comprise feet to act as a base at a lower end of the load bearing leg supports in the assembled configuration. The feet may comprise support pads to substantially spread load carried by the supporting structure in use in the assembled configuration. The feet may be removably connectable the supporting structure.

The supporting structure may comprise locating features to accurately position the supporting structure relative to one or more of the building parts.

The locating features may be provided on both the supporting structure and the building parts to enable accurate location of the supporting structure on the building parts in the assembled configuration.

The locating features may comprise a plurality of pre-drilled holes on the building parts and the supporting structure. The predrilled holes enable accurate location of the supporting structure relative to the building parts and may be alignable in the assembled configuration such that a fixing member may be inserted through each hole to secure the supporting structure to at least one of the building parts. The fixing member may comprise a suitably sized screw.

The locating features may comprise a plurality of pre-drilled holes on an upper surface of the ground floor element(s) and an upper surface of the upper-level floor element(s) and on the feet of the supporting structure. The locating features may also be provided to accurately position an underside of the upper-level floor element and/or the underside of the roof on the supporting structure. An underside of the upper-level floor element and/or the roof may comprise locating features to accurately position the upper-level floor element and/or the roof on the supporting structure.

The locating features may be provided on both the supporting structure and the upperlevel floor element(s) to enable accurate location of the upper-level floor element(s) on the supporting structure in the assembled configuration.

The load bearing cross members may comprise a level support portion to support an underside of the upper-level floor element(s) or the roof in the assembled configuration. The level support portion may comprise a portion that is substantially planar with a relatively large surface area to spread load carried by the structural support in use in the assembled configuration.

The level support portion may comprise a wooden pad.

The temporary reusable parts may further comprise an edge protection system. The edge protection system may be detachably connectable with the building parts to provide a protective barrier along open edges of the building during construction.

Advantageously the edge protection system provides a safety barrier spaced from the outer edges of the building being constructed so that construction workers working above ground on the upper-level floor elements will not be exposed to open edges which present a health and safety hazard.

The edge protection system may comprise a plurality of interconnectable barrier members arranged for connection to a building part in a preselected location. The barrier members may comprise a plurality of interconnectable upright and horizontal posts when in an assembled operational position to provide edge protection on the building.

The edge protection system may comprise a plurality of barrier members arranged vertically in use and connectable to a pre-formed feature on the upper-level floor element(s). Thus, the vertical barrier members may be fastened into the building parts.

The edge protection system may further comprise a plurality of barrier members arranged horizontally in use. The edge protection system may comprise a handrail.

The edge protection system is preferably lightweight and portable. The edge protection system may be formed from aluminium. The edge protection system may comprise aluminium tubing. Thus, the edge protection system may be configured for easy manual handling.

The edge protection system may comprise a plurality of interconnectable barrier members arranged for connection in a preselected location on the upper-level floor element(s). The edge protection system may comprise a plurality of barrier members arranged for erection on the upper-level floor element(s) spaced from any open edge of the floor element(s) by a predetermined distance.

The preselected distance at which the edge protection system is spaced from any open edge of the floor element(s) may be greater than the depth of the panels and columns. Advantageously, this allows the load bearing columns and the non-structural panels to be inserted and affixed to the exterior of the building external to the edge protection system, so that construction workers are not endangered by removal of safety barriers to add wall features or fixings at any stage in the construction process.

The preselected distance at which the edge protection system on the upper-level floor element(s) is spaced from an outer edge may be between around 30cm and 55cm. The The preselected distance at which the edge protection system on the upper-level floor element(s) is spaced from an outer edge may be between around 35cm and 45cm. The preselected distance at which the edge protection system on the upper-level floor element(s) is spaced from an outer edge may be approximately 40cm.

The edge protection system may comprise locating features to accurately position the safety barrier on part of the building. Selected portions of the building parts may comprise locating features to accurately position the edge protection system thereon. The edge protection system and selected building parts may comprise complementary locating features that enable engagement of the edge protection system to the building in an assembled operational position providing edge protection on the building.

At least one of the edge protection system and the building parts may comprise locking features to securely attach the edge protection system to the building.

The locating features may also comprise a locking feature. The locating features may also comprise a locking feature actuable by twisting the vertical barrier members into position during assembly.

The locking feature may be part of the locating feature such that coupling of the edge protection system to the building inherently ensures that the edge protection system is locked into position on the building. Thus, use of the locating features to connect the edge protection system to the building automatically results in the secure locking of the edge protection system in position towards the edge of the building.

The edge protection system may be between around 105cm and 150cm in height. The edge protection system may be at least 90cm in height.

The edge protection system may be utilised at any open edge of the building that would otherwise be open or unprotected and present a hazard to construction workers, such as exposed external edges and internal stairwell gaps.

Thus, the first aspect of the invention enables the construction of high performance, low-carbon dwellings with improved safety at a range of different potential building sites. The pre-fabrication of a number of precision engineered smaller building parts advantageously means that the prefabricated building parts may be stored more efficiently within a warehouse or other storage space. Additionally, haulage costs are reduced for the building kit of parts compared with a modular building, which may require the specialist transportation of wide loads.

According to a second aspect of the invention there is provided a building constructed from the kit of parts of the first aspect of the invention. The building of the second aspect of the invention may conform with Passivhaus standards. The building may be for domestic or commercial use. The building may be a home or an office.

According to a third aspect of the invention there is provided a method of construction of a building using a kit of parts, the method comprising the steps of:

(i) providing a kit of parts including at least one ground floor element, at least one upper-level floor element, a roof, structural columns and non- structural panels;

(ii) providing temporary reusable parts including a supporting structure;

(iii) locating the ground element(s) in a predetermined position;

(iv) assembling the supporting structure on the ground element(s);

(v) assembling the upper-level floor element(s) on the supporting structure and fixing structural columns in predetermined positions between the ground floor element(s) and the upper-level floor element(s);

(vi) assembling the supporting structure on the upper-level floor element(s);

(vii) assembling the roof on the supporting structure;

(viii) fixing structural columns in predetermined positions between the between the upper-level floor element(s) and the roof;

(ix) fixing the non-structural panels in predetermined positions between the ground floor element(s) and the upper-level floor element(s), and between the upper-level floor element(s) and the roof; and

(x) removing the temporary reusable parts including the supporting structure between the ground floor element(s) and the upper-level floor element(s), and between the upper-level floor element(s) and the roof.

Advantageously, building using a kit of parts and the temporary reuseable supporting structure enables the building to be constructed without the need for scaffolding and in this way differs from conventional building methods. Thus, with the method of the invention, the intermediate floor level(s) and the roof are constructed before walls are added to the building. As a result, there is unfettered access to the exterior of the building. Additionally, the footprint required for the construction of the building is reduced, since the supporting structure is located on floor elements within the footprint of the building

The method may include constructing a building within a predetermined building footprint using the kit of parts in step (i) and temporary reusable parts of step (ii).

Step (i) may comprise providing timber-based building parts. Step (i) may comprise forming the upper-level floor element(s), the roof, structural columns and non-structural panels from timber-based materials.

The method of step (i) may involve at least partially forming the building parts from raw timber. Prior to step (i) the timber may be kiln-dried.

The method may involve maintaining the timber-based building parts under controlled conditions. The method may involve maintaining the timber-based building parts within a predetermined temperature and/or humidity range.

The method of step (i) may involve precision manufacturing the building parts from timber. The method of step (i) may involve manufacturing the timber-based building parts to an accuracy of between around +/- 2mm and +/- 8mm. The method of step (i) may involve manufacturing the timber-based building parts to an accuracy of +/- 5mm or less.

The method may comprise wrapping the timber-based building parts in moisture control wraps to maintain the timber in predetermined conditions prior to use in the building construction process. The method may comprise storing the timber-based building parts in a location elevated above ground level to maintain the timber in controllable conditions prior to use in the building process.

The method of step (ii) may comprise providing a supporting structure in the form of load bearing propping structures. The method of step (ii) may comprise providing a supporting structure with feet to spread load carried by the supporting structure. The feet may also facilitate temporary attachment of the supporting structure to the building.

The method of step (ii) may comprise providing a supporting structure with visually identifiable markers to enable accurate assembly of the supporting structure.

The method of step (ii) may comprise providing an incrementally adjustable supporting structure to enable accurate vertical positioning of the supporting structure on the ground floor element(s). The method of step (ii) may comprise providing a supporting structure with threaded legs to enable accurate incremental vertical positioning of the supporting structure on the ground floor element(s).

The method of step (iii) may comprise locating the ground element(s) in a predetermined position on a pre-prepared foundation. All subsequent method steps (v) to (ix) may be performed entirely within the area defined by the preprepared foundation such that the construction of the building is achieved within the predefined building footprint.

The method of step (iv) may comprise connecting the supporting structure at a predetermined location on the ground floor element(s). The method of step (iv) may comprise setting the supporting structure at a predetermined height to support the upper-level floor element(s) at a known spacing from the ground floor element(s).

The method may include providing pre-formed locating features allowing the accurate location of the supporting structure on the ground floor element(s). The method may include providing pre-drilled pilot holes in an upper surface of the ground floor element(s) and attaching the feet of the supporting structure to the ground floor element(s).

The method of step (v) may comprise lifting the first-floor element(s) into position on the supporting structure using lifting equipment. The lifting equipment may include a vehicle mounted crane, telehandler or the like. The method of step (v) may comprise assembling the first-floor element(s) on the supporting structure such that the first-floor element(s) are entirely supported by the supporting structure.

The method may comprise providing temporary reuseable parts in the form of an edge protection system. The method may comprise installing the edge protection system in a predetermined location surrounding exposed edges of the first-floor element(s) to form a protective barrier.

The method may comprise installing the edge protection system in a predetermined location spaced at a known distance from outer edges of the first-floor element(s). The predetermined spacing may allow the installation of the structural columns and non- structural panels to the exterior of the building with the edge protection system in an assembled position.

The method of step (v) may comprise temporarily attaching the supporting structure to an underside of the first-floor element(s).

The method may comprise temporarily connecting the supporting structure at a predetermined location on an upper surface of the first-floor element. The method may comprise setting the supporting structure at a precise predetermined height to support second-floor element(s) at a known spacing from the first-floor element(s).

The method may comprise lifting the second-floor element(s) into position on the supporting structure using lifting equipment. The method may comprise assembling the second-floor element(s) on the supporting structure such that the second-floor element(s) are entirely supported by the supporting structure.

The method may comprise installing edge protection around exposed edges of the second-floor element(s). The method may comprise temporarily attaching the supporting structure to an underside of the second-floor element.

The method of step (vi) may comprise temporarily connecting the supporting structure at a predetermined location on an upper surface of the second-floor element(s). The method of step (vi) may comprise setting the supporting structure at a precise predetermined height to support at least one attic floor element at a known spacing from the second-floor element(s).

The method of step (vi) may comprise lifting the attic floor element(s) into position on the supporting structure using lifting equipment. The method may comprise assembling the attic floor element(s) on the supporting structure such that the attic floor element(s) are entirely supported by the supporting structure.

The method may comprise installing edge protection around exposed edges of the attic floor element(s). The method may comprise temporarily attaching the supporting structure to an underside of the attic floor element(s).

The method may comprise temporarily connecting the supporting structure at a predetermined location on an upper surface of the attic floor element(s). The method may comprise setting the supporting structure at a precise predetermined height to support the roof at a known pitch and spacing relative to the attic floor element(s).

The method of step (vii) may comprise lifting the roof into position on the supporting structure using lifting equipment. The method may comprise assembling the roof on the supporting structure such that the roof is entirely supported by the supporting structure.

The method of step (viii) may comprise lifting the structural panels into predetermined positions between the ground element and the upper-level floor elements, and between the upper-level floor elements and the roof. The method of step (viii) may comprise fixing the structural panels into predetermined positions such that the structural panels transfer load from the building through the structural columns and floor element(s) to the foundation.

The method of step (viii) may comprise fixing the structural columns in predetermined positions to form a grid system with a load bearing capacity that transfers line and point loads through predetermined parts of the building, supported by the building foundation. Thus, the load bearing capacity of the building is provided by the structural columns that channel loads into a supporting grid comprising the structural columns and floor elements spanning between the columns so that loads are deliberately distributed in specific locations.

The method of step (ix) may comprise hanging the non-structural panels in predetermined positions between the ground floor element(s) and the upper-level floor element(s), and between the upper-level floor element(s) and the roof. The method of step (ix) may comprise hanging the non-structural panels using load-bearing brackets applied to a structural building part such that the mass of the non-structural panels is carried via the load bearing bracket connection at their upper end.

The method may include finishing steps such as: securely interconnecting building parts; tying in building parts; adding vapour protection; tightening fixings; adding pipework; installing electrical, heating and/or plumbing systems; incorporating further insulation; filling and/or covering gaps where access and/or fixings were required; sealing any remaining gaps; incorporating fire retardant features; installing cladding, and the like.

The method may include constructing a building that is Passivhaus compliant. The building method may be constructed using a process that generates net-zero emissions.

The method may include following the method steps in the listed order. Alternatively, some method steps may be followed in a different order. Preferably, the method of the invention involves locating the floor elements prior to the completion of the walls.

According to a fourth aspect of the invention there is provided a reusable supporting structure, wherein the supporting structure is movable between an assembled configuration in which the supporting structure is arranged to structurally support elements of a building and a transport configuration is which the supporting structure is disassembled for ease of transport, the reusable supporting structure comprising: a plurality of inter-connectable structural supports comprising load bearing leg supports, load bearing cross members and bracing members; wherein the structural supports are connectable into the assembled configuration for placement on a substantially level floor element and configurable at a specific predetermined spacing from the floor element to support the load of a building element thereabove.

Further optional features of the reusable supporting structure are set out in numbered paragraphs 1 to 18.

According to a fifth aspect of the invention there is provided an edge protection system to provide a protective barrier along open edges of a building, the edge protection system comprising a plurality of interconnectable upright and substantially perpendicular barrier members, and locating features to accurately position the safety barrier on part of a building; wherein the edge protection system is detachably connectable to a floor element of a building at a predetermined location using the locating features.

Further optional features of the reusable supporting structure are set out in numbered paragraphs 19 to 24.

Any of the first, second, third, fourth, or fifth aspects of the invention may be combined with any other aspect, feature or embodiment described in the specification or shown in the figures where appropriate.

Embodiments of the invention are now described with reference to the following drawings in which:

Figures 1 a to 1 h are sequential perspective views of one embodiment of a building construction method according to the invention;

Figures 2a to 2f are perspective and side views of a supporting structure in the form of a cassette propping system;

Figures 3a to 3e are perspective views of the cassette propping system in use on the building;

Figures 4a and 4b are perspective views of structural columns in the form of plybox square section columns;

Figures 5a and 5b are perspective views of non-structural panels in the form of glazing cassettes;

Figure 6 is a perspective view of a partially constructed building; Figures 7a to 7e are perspective views of an edge protection system; and

Figure 8 is a load bearing connection bracket.

The building system using the method of construction of the invention allows off-site facilities to fabricate non-volumetric precision manufactured building parts and components which are assembled on a building site using simple assembly processes. The building is formed from a prefabricated kit of building parts including a collection of floor elements or cassettes 10, 12, a roof 14, structural columns 16 and non-structural panels 18. According to the present embodiment, the kit of parts is used for the construction of a single dwelling 20 of two storeys plus a loft area. The resulting building has a ground floor level, a first-floor level and a pitched roof 14 with a centrally located ridge line and an attic floor defining a loft space.

Floor elements or cassettes

There are two primary types of floor element or cassette: perimeter cassettes having three external edges; and intermediate cassettes with two cassette interfacing edges. The cassettes are variable in length and width are configured on the building plan based on a joist spacing which is variable according to the size of the building.

The ground-floor level cassettes shown generally at 10 in the figures are formed from glass-reinforced plastics (GRP), which provide a low carbon moisture resistant alternative to traditional ground level construction materials. Multiple cassettes 10 are bolted together to form a ground level flooring onto which the rest of the building is constructed. The ground-floor level cassettes 10 act as an interface between the foundations shown generally at 11 in figure 5a. The foundations 11 are built on site, whereas the rest of the building is fabricated in parts off site is transported and assembled on site. The ground floor cassette structure 10 is formed from GRP channels with GRP cleats. The ground floor cassettes 10 are of a fixed depth due to the GRP channels, but are variable in length and width. GRP panels on the bottom surface are glued with low strength flexible adhesive. GRP panels along the perimeter and in structurally critical zones are glued with high strength structural epoxy or similar. A structural deck is formed from tongue and groove oriented strand board (OSB). Pre-drilled holes are provided for onsite cassette connection with GRP cleats. Cavities are left open to provide access to foundation fixings.

Upper-level floor elements 12 (including first-floor, second-floor and/or attic cassettes) are formed from timber. Each cassette comprises timber engineered I-section joists fixed to upper and lower sheets of 18mm tongue and groove oriented strand board (OSB). All joints of the upper-level floor elements are fully glued and the boards are screwed to the I -section joists. Two 10mm layers of Fermacell® boarding with taped joins provide fire resistance to the upper-level floor structure. Edges of the OSB sheet overlap adjacent cassettes to form a lap joint. Upper-level floor cassettes are of a fixed depth based on the selected engineered I-beam depth of 220mm. Multiple upper-level cassettes 12 are fixed together to form a structural horizontal floor panel.

Roof

The roof 14 is formed from a series of interconnected roof elements or cassettes. Roof cassettes are formed from 350mm deep timber engineered I-joists with upper and lower OSB. The roof cassettes are designed to completely cover the building with no joints between different types of cassette on the roof surface. Ridge detail is a simple bearing connection which is fixed together on site with screws.

Structural Columns

The structural columns 16 act as shear walls and provide both vertical load bearing action and resistance to horizontal wind loads. Examples of structural columns are shown in figures 4a and 4b. Structural columns 16 in the form of plybox and square section columns are the building parts primary structural components that are designed to support the building in its finished state. The structural columns 16 are designed to be manufactured in different heights to accommodate different floor level spacing and the plybox column is manufactured in different widths in fixed increments.

Each structural column 16 has an attached load-bearing steel connection bracket 50 fixed at the upper edge (shown in figures 4a, 4b and 8). The load-bearing connection brackets 50 are provided for attaching non-structural panels to the building such that the non-structural panels 18 are ‘hung’ from the brackets 50 rather than supported from beneath. Structural columns 16 form the primary load bearing structure, while non- structural wall cassettes 18 are secondary infill elements.

Surface column boarding presents a uniform internal surface to the building. Fire boarding is provided on a lower section of ground-floor structural columns 16 only, to protect the GRP ground floor cassette connection bracket.

Non-structural panels

The wall cassettes are non-structural panels 18 which provide the performance layers of the facade as well as supporting the cladding. Wall cassettes are designed to be manufactured in a plurality of different dimensions to achieve varied architectural layouts. Vertical facade cassettes form one type of the non-structural wall panel or cassette. Vertical facade cassettes comprise a timber-based infill panel. The ground floor variant of the vertical facade cassettes have a non-timber footing to ensure longevity.

Glazing and doorway panels or cassettes are shown in Figures 5a and 5b are other examples of non-structural cassettes 18 providing framing to windows and doors. The glazing cassettes have an external framing zone with counter orientated batons of 45x45mm to create a rigid frame with an 18mm plywood sheath. All cavities are filled with mineral wool insulation. Doorway cassettes are non-structural panels 18 providing openings to floor level to create a preinstalled doorway. Doorway cassettes have a GRP threshold structural member providing a timber free solid base to increase doorway and frame stiffness. Threshold height is matched to the finished floor level at the bottom of each doorway. In order to minimise the thickness of the external walls, the structural and facade cassettes are designed to integrate together effectively to allow the structure of the building to disappear into the wall.

Wall cassettes have two insulation zones - an outer insulation zone (which is continuous around the outside of the building) and an inner insulation zone, which is broken by the structure of the building. In order for the insulation to be continuous, the cassette has a recessed form, so the cassette can overlap the structure on the outside. In order for the window or door to penetrate the building envelope, the wall cassette is used to provide insulation behind the structure, which then stops at the window framing. The tolerance strategy ensures that the wall cassettes always have adequate movement between structural members whilst prioritising closer gaps on the external component. This ensures the high performance of the building envelope.

Tolerances

The building method of the invention using a kit of parts demands high tolerances when compared to the site-based construction industry. The high accuracy of prefabricated timber building parts is achievable by off-site precision manufacturing processes such as the use of jigs, dedicated work surfaces and repeatable processing. In addition, computer numerical control (CNC) processes ensure accurate sizing of components and siting of features such as pre-drilled holes for locating and aligning construction components.

The building system of the present invention relies on multiple elements in panel form being assembled on site with a high degree of accuracy. Predetermined acceptable tolerances are attributed to building parts so that all the building parts fit together on site without clashes or gaps.

Guiding strategies have been developed to ensure the tight tolerances required for the building. The ground floor elements 10 or cassette assembly can accommodate loose tolerances of the foundation as well as the tighter tolerance of the remaining building parts. The location of the upper-level floor cassettes (including the roof) are carefully controlled by the assembly of the supporting structure in the form of an installation propping system 20. Vertical levels of the installation propping system 20 are controlled and laser measured to ensure high accuracy.

A specified and repeatable construction sequence ensures the correct assembly and consistent performance of the finished building.

Parts structure - Installation

The supporting structure is provided in the form of an installation propping system shown generally at 20 in figures 2a to 2f. The installation propping system 20 is not a permanent building component, but provides a cassette propping system to temporarily support upper-level floor cassettes 12 during the installation phase of the building. The installation propping system 20 is a braced 4-prop or 6-prop structure creating the form of a cuboid when assembled.

The installation propping system 20 is formed from modular prop components which have a high load capacity when assembled. Legs or vertical supports 26 are provided in a range of sizes, each with continuous vertical slots to allow horizontal frames or timber spread beams 22 to be fitted quickly and securely at the optimum height. Screw jacks can be fitted at the top and bottom of each leg 26, offering vertical adjustment. A range of horizontal frames 22 are available in different sizes.

Vertical supports, props or legs 26 use a threaded system to give continuous adjustment and allow for multiple different ceiling heights. The threaded system also advantageously provides an ability to gradually release a load. The installation propping system 20 has inherent flexibility. Multiple props can be bolted together to make an extra-long propping solution for double height spaces. Retaining clips are provided to lock the length of a prop. A lower end of each leg 26 is provided with a detachable foot 24 to spread the load carried by the installation propping system 20 and stabilise the structure. All props are made from aluminium so they are lightweight and corrosion resistant. The installation propping system 20 system is designed to be assembled and dismantled by operatives on site allowing easy transport and storage.

The temporary installation propping system 20 makes it necessary for operatives to be working on an elevated upper-floor cassette 12 while installing the wall cassettes 18 and structural columns 16. Until all vertical columns and panels 16, 18 are fully installed, exposed edges of the building and around stairwells require edge protection to eliminate the risk of falling from height.

Temporary works in the form of an edge protection system is shown generally at 40 in figures 7a to 7e. The edge protection system 40 consists of upright posts 44, each post 44 provided with two mounting brackets 45 located centrally and towards the upper end of the vertical post 44. The mounting brackets 45 are arranged to receive horizontal barrier struts 47, which act as barriers and/or a handrail. The edge protection system 40 further comprises a mounting plate 49 having a bayonet fitting 48 extending therethrough. The bayonet fitting 48 receives a lower end of the upright post 44, which is twisted to interlock the vertical post 44 and the mounting plate 49. The mounting plate 49 is fixed to an upper surface of the upper-level floor element 12 by aligning pre-drilled holes in the floor element(s) and the mounting plate 49 and adding screws to secure the mounting plate to the structure of the building. The mounting plates 49 for the edge protection system 40 are spaced from the edge of the floor element(s) to allow space to accommodate and install the structural columns 16 and non-structural panels 18.

The edge protection system 40 is formed from aluminium so it is lightweight and easy to manipulate. The edge protection system 40 is quick to install and advantageously does not obscure the working areas where vertical panels 16, 18 are to be installed.

Construction

According to one embodiment of the invention the sequential method of building construction using a kit of parts is shown in figures 1 a to 1 h. The first step required prior to building from the kit of parts is substructure/foundation construction. Prior to work commencing on site, geotechnical surveys are undertaken. Generic specifications for the available foundation options are selected and designed according to site specific conditions.

Foundations are designed based on the specific site conditions in the locality of each building. The building system may be used with all traditional domestic foundation solutions. All foundations require attention to dimensional accuracy. The construction of the building from a kit of parts is based on an optimised model where significant amounts of the construction process happen off site with certain processes finished onsite. The onsite assembly and fixing processes are undertaken quickly in chronological order and are based upon delivering a building from a kit of parts of optimal quality and considered design.

Substructure elements are constructed on site, including any levelling of the site and laying down drainage. Both during and post construction, foundations are surveyed to ensure they are within the site assembly tolerances for the cassettes 10. Although the GRP ground-floor cassette 10 is intended to act as an intermediary between the modular system and the site-built foundation, it is important that the structurally critical elements are adequately supported. Cassette 10 locations are marked onto the foundations 1 1 to simplify the positioning of the GRP ground floor element cassettes. The ground bearing location for the cassettes 10 must be accurately level prior to the arrival of the cassettes 10 on site. Once foundation construction is complete, the GRP ground floor cassettes 10 are placed and levelled.

It is common that the ground around the building transitions into an unclean or muddy area on traditional residential building sites due to the high traffic and use of large machinery. The building system of the invention is designed to avoid a messy worksite and use of traditional scaffolding. A muddy site is unsafe and unpleasant, potentially creating the need for cleaning due to transfer of mud under foot and splashback. This extends build time and creates the additional task of landscaping and/or cleaning after the building construction is complete. Temporary roadway matting can be used to protect the ground surrounding the building site. The ground-floor structure is formed using the sealed composite ground-floor cassettes 10 formed from pultruded GRP. The GRP ground-floor cassettes 10 may form a suspended floor where cassettes 10 span perpendicular to the predetermined ridge direction. The maximum span of the ground floor cassette 10 is 6m; the floor is supported at ends (and centrally if required) by linear foundation members (strip footings, ground beams on top of screw piles, and the like). If the site conditions are suitable, ground floor cassettes 10 may be laid directly on compacted hardcore.

As cassettes 10 are laid down, foundation anchor points are engaged and cleats between cassettes are connected in the following order. The central intermediate cassette is placed onto the foundations 11 and surveyed as necessary to ensure accuracy and foundation anchors are engaged. The cassette 10 is locked into position. An intermediate cassette 10 is placed onto the foundations 1 1 , and cleats used to fix cassettes 10 together are engaged. After the cleats are attached, the foundation anchor points are engaged. Once all cassettes 10 are laid, cleated together, and fixed to foundations 1 1 , the ‘trenches’ between each cassette 10 are sealed and filled. Areas around the cleat and foundation fixing bracket are painted with brushed on, liquid- applied waterproofing damp proof membrane. Joining tape is applied to internal gaps between cassettes 10. All space in the trench cavity is filled with mineral wool insulation. Top panels are adhered to the exposed area of joists with low strength flexible glue of the same type as used to stick the top panels to the joists. Sealing tape is applied to the top surface of the panel to finish the joint.

The next step is the erection of installation propping system 20. The installation propping system 20 is shipped to site in component form and requires assembly. The propping system 20 is designed to work at fixed heights and the dimensions of the building determine the level at which the propping system 20 should be set. The feet alignment pads 24 should be fixed to the GRP ground floor cassette 10 on arrival at site, or off-site in the factory prior to transportation. Installation propping system 20 head alignment guides should also be installed on the underside of the timber of the first-floor cassettes 12, and feet alignment pads 24 on the top surface (for later location of roof propping). Props 26 are fully adjustable and 4 props per cuboid are required for the installation propping system 20. A jig is manufactured to be used by operatives on site to quickly and accurately set the height of each individual prop 26.

The installation propping system 20 components (props and ledger frames) are manoeuvred onto position on GRP floor element 10, assembled in place on the feet alignment pads and bolted together. Each foot plate of the installation propping system 20 should be fixed into the pre-attached foot alignment pad. The foot 24 of the prop 27 is secured in place using wing nuts. Timber spread beams 22 are installed on top of the propping system 20 into brackets attached to the prop head. At this point the system 20 is ready for the installation of the first-floor timber cassettes 12.

As the building parts (wall panels 16, 18 floor 12 and roof cassettes 14) are a large format design, a form of lifting device is required for the entire primary construction process. Building parts are typically designed to be lifted from above by a construction telehandler on site. Telehandlers are relatively small multi-purpose lifting machines available for hire or purchase. They are suitable for unpaved sites and are sufficiently manoeuvrable for smaller, single dwellings. The machine features a boom which can support interchangeable attachments. The primary attachments utilised are: hydraulic winch for the lifting and placement of cassettes; and a work platform for providing access to localised areas at a high level.

Propping system 20 alignment points are installed or pre-installed on the underside and top side of the first-floor cassettes 12. The first-floor timber cassettes 12 are lowered onto the installation propping system 20. First-floor timber cassettes 12 are fixed together on site using an OSB lapping detail. Operatives at ground level use ropes attached to rope eyes temporarily screwed to the cassette 12 to guide cassettes 12 into position. Propping system 20 head alignment guides (on a lower surface of the floor cassette 12) should enable accurate location of the cassette 12 onto the propping system 20 with a tolerance of +/-20mm.

The next step is the installation of the load bearing columns 16 between the groundfloor and first-floor. Ply-box columns are installed before square section columns. The columns 16 have temporary lifting points attached to enable handling with the onsite telehandler. The ply-box columns are lifted into predetermined positions onto the GRP floor cassettes 10. Installation of the ply-box columns is completed by hand tightening nuts and bolts into base brackets of ply-box column. The brackets at the foot of the plybox column are shimmed in order to prevent lateral movement of the column. Steel wedge shaped plates of varying thickness are packed within a column shimming zone to prevent column movement once the column 16 is in the correct location. Once a survey shows that the ply-box columns are in the correct location, shims are packed in position and bolts are tightened at the base of each column to a torque of 95Nm.

Cavities at the base of the ply-box columns are fully filled with mineral wool insulation. A low level mobile scaffolding step (or set of steps) is used to gain access to the top of the ply-box columns. Two steel first floor cassette 12 connection brackets are installed on either side of the ply-box column using screws. The bracket self-locates on the internal face of the ply-box column and abuts the underside of the timber floor cassette 12. With the column bracket held in place between the plybox column and the underside of floor cassette 12 perimeter beam, screws are inserted into the plybox column and the floor cassette perimeter beam to make the connection. The lifting gear is disconnected and the lifting points are unscrewed from the rear face of the plybox column.

Square section columns are then attached to the GRP floor cassette 10 and secured to the timber floor cassette 12. The square section columns weigh approximately 25kg and it is possible to move these columns using a two-person lift. Therefore, no lifting point is attached to the square section columns. The installation process is similar to that of the ply box columns, except no shimming is required with the square timber columns. Bolts are installed into the base bracket of the column, but due to space restrictions the angle fixing on the GRP floor cassette 10 is threaded as there is no access to the back of the connection due to fire board. The position of the columns are surveyed and adjustments made to ensure the column is in its correct position. Once the survey shows that the column is in the correct location, bolts are tightened at the base of each column to a torque of 95 Nm. Cavities at the bases of each column are to be fully filled with mineral wool insulation. A low level mobile scaffolding step (or set of steps) is used to gain access to the top of the column. Two steel first floor cassette connection brackets are installed on either side of the column using screws. Selflocating brackets are placed on the face of each column and pressed against the underside of the timber first floor cassette 12 perimeter beam. Once the column bracket is held in place between the square section column and underside of floor cassette perimeter beam screws are inserted into the timber column and the floor cassette perimeter beam to make the connection.

Non-structural panels 18 in the form of ground-floor wall cassettes and glazing cassettes are installed next. The column connection brackets 50 at the top on each side of the columns are the same brackets which are used to fix the wall cassettes into position. Thus, the non-structural panels 18 are supported from above and ‘hung’ from the load-bearing structure of the building. Prior to moving each wall cassette into place, compressible foam strips are applied to the two outer vertical edges and the two vertical internal edges. These strips can be pre-applied off-site.

The wall cassette is presented to the aperture and manoeuvred into place between the load bearing columns 16 on either side, with the GRP floor cassette 10 below and first floor cassette 12 above. The wall cassette is pulled up against the underside of the floor cassette ring beam and held in position while fixings are applied between the structural column 16 and the wall cassette 18 from the inside of the structure. Wall cassettes with an internal insulation zone of greater than 2000mm wide require a stiffening plate at the top level between the first-floor cassette and the wall cassette. This is inserted once the wall cassette is in place. Once the wall cassette is screwed into position, the lifting point and lifting gear are removed. All typical wall and glazing cassettes 18 are installed using the same process.

When all cassettes on the ground-level have been installed, stitch plates, which are steel plates screwed on to the outside of the wall cassettes 18 are attached on the split lines between wall panels and glazing cassettes. Two stitch plates are required per split line between either a wall cassette or a glazing cassette. After stitch plate installation, breather membrane tape is installed over the split line. A 150mm wide breather membrane specific tape is used, such as Tyvek™ Flexwrap Tape.

For the next construction stage, operatives will be required to work at an elevated level on the first-floor cassettes 12 to continue with the building process. The first-floor surface is made safe for operatives to work at height using the edge protection system 40. The edge protection system 40 is installed by twisting the upright posts 44 into the bayonet fittings 48 attached to the feet 49 that were pre-attached onto the first-floor cassettes 12. The horizontal barrier struts 47 are received in the mounting brackets 45 for a quick and easy assembly to provide a safety barrier around all exposed edges of the building.

As on lower levels, the installation propping system 20 alignment pads are pre-fixed to the top surface of the first-floor cassettes 12 in order to accept the installation propping system 20 legs or support props 27. The installation propping system 20 is fixed on the first-floor cassette 12. In void spaces, additional installation propping system 20 components may be required on the ground level to support the feet 24 of the propping system 20 on the level above.

Second floor (attic) timber cassettes 12 are installed onto the propping system 20. The connection details and processes are identical for all timber floor cassettes. When all cassettes are in place, the position of the perimeter beam is surveyed for lateral position and verticality.

Plybox structural columns 16 are installed next. Columns 16 are lifted into place and connected at their base. Columns 16 have a different base connection bracket to those used at the ground floor level. The same connection bracket that was used at the top of the column is now positioned at the bottom of the column. The connection at the top of the first-floor ply box is identical to the connection at the top of the ground floor plybox column. Square section structural columns are installed next. As with the plybox columns, the base connection differs from the ground floor columns. The connection at the top of the first-floor square section column is identical to the connection at the top of the ground floor square section column.

Once all structural columns 16 are installed, the wall and glazing cassettes 18 installed. The process is almost identical to the installation sequence for the ground floor wall cassettes except that the lower connection is now identical to the upper connection.

The present embodiment covers a building that has a pitched roof with attic finishing.

The second floor (attic) surface is made safe for operatives to work at height using the edge protection system 40. Operatives should access the upper floor level and apply screws into the OSB lapping detail between the second floor (attic) cassettes to fix them together. The installation propping system 20 is assembled on attic floor engaging legs with pre-fixed installation alignment pads. Roof cassettes 14 are craned into position and lowered onto the installation propping system 20. Operatives at ground level use ropes attached to rope eyes temporarily screwed to the cassette to guide cassettes into position. Installation propping system 20 alignment guides assist the seating of cassettes. Propping system 20 alignment guides are of timber construction for pitch roof cassettes as the variety of roof pitches make the fabrication of steel alignment guides inefficient.

Edge protection to the second floor (attic) surface is removed to allow the roof cassettes to be lowered into place. The roof features OSB lapping joints dictate the order of installation. As the roof cassettes are lowered into place, operatives ensure the edge of the cassette is engaged with the roof cassette capture bracket (no fixings between this bracket and the roof are required) Once all the roof cassettes 14 are in place, the floor surface is made safe for operatives to work at height: gable ends apertures require edge protection using the edge protection system 40. The position of the ridge down stand and the exposed gable perimeter beam is surveyed for lateral position and verticality. Operatives on the second floor inspect along the underside of the roof ridge line. A down stand is visible at the joint where one cassette meets another. Two wood screws are inserted into the pre-drilled holes to secure the roof cassettes 14 lower ridge fixing point together. Shimming may be required between the timber faces to ensure tight contact between the two cassettes. Plastic high-load packers may be used for shimming as required. Positions are to be clearly marked off site to identify the locations where the screws are inserted are directly below the joists in the ceiling cassette

Plybox columns 18 are installed between the second floor and the gable end perimeter beam. Columns are lifted into place and a base connection is applied. The base connection is identical to the connections as used on the first-floor level. The connection at the top of the first-floor ply box is similar to the connection at the top of the ground floor plybox column. Square section columns are inserted between the second floor and the gable end perimeter beam. Columns are lifted into place and a base connection is applied. The base connection is identical to the connections as used on the first-floor level. The connection at the top of the second-floor square section column is similar to the connection at the top of the ground floor square section column. There is also a column to the ridge connection. This installed in the same way as the other columns but the brackets are located on either side of the ridge down stand.

Wall cassettes 18 are installed into the gable aperture between the structural columns 16. The connections to the wall cassettes are identical to the connections for the first- floor cassettes. Once all cassettes 16, 18 are installed, stitch plates and vapour control layer (VCL) tape are applied to both the first floor and gable end wall cassettes. If a staircase is required for a habitable second floor it is a component-based design which can be brought into the house and assembled in-situ. For attics (non-habitable space) a standard access hatch within the timber floor cassettes is required.

Operatives are then required to access the pitched roof to complete the installation. A boomed access platform is used to provide access to the pitched roof. Screws are inserted into the OSB lapping details between the flat roof cassettes to fix them together. This is a delayed operation from the roof cassette installation. The roof cassettes have a pre-applied breather membrane: locations for the OSB lapping connection will be left open. A flap of breather membrane will be temporarily taped back on itself. After OSB screws are inserted, this flap will be released and folded over the joint and taped in place. Breather membrane is lapped and taped to the vertical wall cassettes using the same method. Operatives move along the roof ridge line. A vertical up stand will be visible at the joint where one cassette meets another. Wood screws are inserted into the pre-drilled holes to secure the roof cassettes upper ridge fixing point. As with the down stand connection, shimming may be required and plastic high-load packers can be used. Locations for screws are clearly marked off site to ensure screws are directly above roof joists. The pitched roof cassette accepts a lightweight cladding system which is an optional feature having pre-installed rails where possible. The cladding design should incorporate the ridge flashing and also flashing to the vertical facade panels.

Internal Vapour Control Layer Completion or VCL lapping internally will be a single process. All internal surfaces of the wall cassettes (behind the service zone) will be coated off-site with a liquid applied VCL. This product dries to a ~1 mm thick rubber membrane. A fibre enhanced version of this material (applied on site) is available for brush on applications. After the building is assembled and structurally self-supporting with all installation aids removed, the gaps between the cassettes (both vertical and horizontal) will be painted with the product to complete the internal VCL sealing layer. During this process any damage that may have occurred during transport is remedied.

Internal gaps are present in all locations where one cassette meets another. A hidden push-fit fixing is provided to secure infill panels in place. Operatives are provided with a jig to ascertain the size of each aperture and cut panels to size accurately on site. The male half of the push-fit fixing is pre-installed onto the wall cassettes and with the assistance of some small assembly guides, the female part is attachable to the panels, which are then pushed into place. Small amounts of acoustic sealant may be required when installing these boards.

All houses should ideally feature some functional attic space. The primary extract and exhaust vents are positioned at high level, and additional ductwork will be required to service second floor rooms. It is expected that the number of ducts required to provide those connections will be impractical to run within the second-floor cassette, hence the ideal of having the attic space. The expectation is that the service spine incorporated in the first-floor cassette should not be required in the second-floor cassette. Power cables can also be run in the loft space, with local penetrations allowing distribution to the rooms below. Again, this is to drive a simple construction of the cassette. For buildings with flat roofs, an enlarged service zone (similar to a suspended ceiling) will be provided to distribute these ducts.

Wet services (kitchen, bathrooms, toilets, utility room and mechanical, electrical, plumbing (MEP) cupboard — excluding heating distribution) are grouped into an area of the house, and that area should be consistent on all floors of the house. This simplifies the distribution of wet services and minimises the need for additional penetrations in the floor cassettes for soil drainpipes. Air extract vents are typically only required in wet areas so the duct distribution will also be simplified (avoiding long runs to service single rooms not grouped together). This also simplifies the external ground works as it is likely all waste pipes can drain to a single point. The system generally assumes that all soil stacks are run internally, thereby keeping the external appearance of the building aesthetically clean. The soil stack should run to the loft space and vent internally with an air admittance valve.

Different roofs

The described embodiment has a pitched roof with a central ridge. However, different roof options are possible, such as a pitched roof with an asymmetric ridge or a flat roof. If the building has a pitched roof, the slope of the roof may vary between 20° and 55°. In buildings with flat roofs, the cassettes are asymmetric, i.e. the ‘ridge’ (or connection between two cassettes) is offset from the building centre and positioned over the internal supporting wall.

A single cassette design achieves all roof variants. The pitch of the roof cassette varies from 55 down to a minimum of 20 degrees for pitched roof designs which have a central ridge connection. For flat roof architecture, the pitch is set to 3 degrees and the ‘ridge’ connection moves to the load bearing wall for buildings over 6m wide. For buildings under 6m, a single flat cassette is used.

Building performance

The building resulting from the kit of parts provides a high-performance building envelope that minimises energy needs. The finished building adheres to the Passivhaus standard: the internationally recognised, sustainable construction standard developed by the Passivhaus Institute in Darmstadt, Germany. The Passivhaus Institute has set a series of criteria for Passivhaus certified components to ensure that they meet the standards stringent levels of comfort, hygiene and energy efficiency requirements.

The constructed building has good lateral stability. Floor and roof cassettes provide diaphragm action, transferring lateral loads onto the plybox columns positioned in walls parallel to the direction of the load. Plybox columns act as vertical cantilevers transferring lateral loads to the foundations as a horizontal force and a vertical push-pull acting at the corner of the plybox column. Depending on the dimensions of the building, the number and size of plybox columns may vary. If the depth of the building is more than 6m, an internal load bearing wall is required that is assumed to contribute to the lateral stability of the building. This wall is parallel to the ridge and is referred to as a spine wall. If the width of the building is more than 12m, an internal load bearing wall is introduced in the direction perpendicular to the ridge.

If the building depth is less than 6m, the floor cassette is simply supported. If the building depth is more than 6m, a load bearing spine wall is required. If the spine wall is offset on the upper floor, individual building specific joist spacing calculation is to be carried out.

Different

The building parts can be configured in multiple arrangements to achieve the desired layout, size, dimensions, fenestration, and layout. The building system design aims to provide a kit of parts that can provide the maximum architectural design flexibility. To enable flexible architecture, each of the building parts is subject to a collection of structural rules resulting in panels with variable dimensional values. Some dimensions are fixed while others are variable to configure the individual panels and cassettes to a building design within certain rules.

According to the present embodiment architectural rules are provided as follows:

1 ) An internal structural load bearing wall is required. This wall must be located a maximum of 6m from the external wall

2) The load bearing wall must run in line with the roof ridge. If a load bearing wall runs perpendicular to the roof, an alternative structural solution is required to support the roof.

3) For ease of handling panel heights are single storey and require a joint at each floor.

4) All external openings are less than 3m wide.

5) For pitched roof houses the roof pitch can vary between 20 to 55 degrees.

6) A flat roof is facilitated by the system with a 3 degree pitch.

7) Position of the stair is adjustable based on structural rules and a desired floor-plan.

8) The maximum building (ridge) height is 15 m.

9) Unlimited theoretical building width and length. 10) The roof can be flat or symmetric pitched with a slope of up to 55 degrees. If the roof is steeper than 35 degrees, the building may not be deeper than 10.8m (i.e. footprint not larger than 10.8m x 18m).

11 ) If internal spans exceed 6m with the building depth (perpendicular to the ridge) being more than 6m, an internal load bearing wall is required and must be located no more than 6m from the furthest facade wall. The load bearing wall must run parallel with the roof ridge.

12) The roof can be flat or symmetric pitched with a slope of up to 55 degrees. If the roof is steeper than 35 degrees, the building may not be deeper than 10.8m (i.e. footprint not larger than 10.8 x 18m).

13) If the building width (dimension parallel to the ridge) exceeds 15m, an internal load bearing wall is required that is perpendicular to the ridge (i.e. for buildings with footprint larger than 6 x 15m, two internal load bearing walls are required, one in each direction).

14) Depending on the size of the building, a minimum amount of box columns are introduced in each facade.

15) Position of the stair core and required opening must be adjacent to an external wall.

16) Perimeter foundation only for houses <6m in depth.

17) Additional mid span continuous foundation element in addition to perimeter foundation for houses with depths of >6m to <12m.

18) Facade apertures for full height glazing or doors are possible in any elevation and at any level.

Modifications, variations and improvements can be made without departing from the scope of the invention. Relative terms such as “upper”, “lower”, and/or “central” are used for illustrative purposes only and are not intended to limit the scope of the invention.

According to an alternative embodiment, the adhesive free timber I-beam has flanges joined to a central length of timber by a plurality of gripping members in the form of teeth or barbs to securely interconnect the flanges with the central length of timber to provide an l-shaped cross-section.

While the embodiments described relate to detached homes having two storeys and an attic, it is also possible to use a similar methodology and design principles to design different buildings such as connected dwellings or commercial/office space. For example, connected dwellings will use party walls. A similar system using a comparable kits of parts can be developed and designed to form an alternative type or arrangement of building but adhering to the same principles of a precision manufactured kit of parts and temporary reusable works to assist with onsite construction and safety.

Numbered paragraphs

1 . A reusable supporting structure, wherein the supporting structure is movable between an assembled configuration in which the supporting structure is arranged to structurally support elements of a building and a transport configuration is which the supporting structure is disassembled for ease of transport, the reusable supporting structure comprising: a plurality of inter-connectable structural supports comprising load bearing leg supports, load bearing cross members and bracing members; wherein the structural supports are connectable into the assembled configuration for placement on a substantially level floor element and configurable at a specific predetermined spacing from the floor element to support the load of a building element thereabove.

2. A reusable supporting structure according to paragraph 1 , wherein the load bearing leg supports are arranged for substantially vertical orientation in the assembled configuration and the load bearing cross members are arranged for substantially horizontal orientation in the assembled configuration.

3. A reusable supporting structure according to paragraphs 1 or 2, wherein the supporting structure comprises a plurality of structural supports interconnectable in the assembled configuration to support the load from an upper-level floor element on a ground floor element and to support the load of a roof on the upper-level floor element.

4. A reusable supporting structure according to any one of paragraphs 1 to 3, wherein the supporting structure comprises adjustable length structural supports.

5. A reusable supporting structure according to paragraph 4, wherein the load bearing leg supports are adjustable to enable use of the supporting structure at specific predetermined different heights.

6. A reusable supporting structure according to paragraphs 4 or 5, wherein the load bearing cross members are selectable to enable the supporting structure to support a required surface area.

7. A reusable supporting structure according to any one of paragraphs 4 to 6, wherein the structural supports comprise a threaded mechanism to allow incremental adjustments in the height of the supporting structure.

8. A reusable supporting structure according to any preceding paragraph, wherein the structural supports are formed from aluminium.

9. A reusable supporting structure according to any preceding paragraph, comprising a substantially cuboid supporting structure in the assembled configuration.

10. A reusable supporting structure according to any preceding paragraph, comprising at least four load bearing leg supports and at least four load bearing cross members extending perpendicular to and between the load bearing leg supports.

1 1. A reusable supporting structure according to paragraph 10, wherein the load bearing leg supports and load bearing cross member structural supports are linked using crosswise bracing members in the assembled configuration.

12. A reusable supporting structure according to paragraph 11 , wherein the bracing members are located between the load bearing leg supports and/or load bearing cross members to reinforce the supporting structure to support the load of the at least one upper level floor element and/or a roof in the assembled configuration.

13. A reusable supporting structure according to any preceding paragraph, comprising feet removably connectable to the load bearing leg supports in the assembled configuration. 14. A reusable supporting structure according to paragraph 13, wherein the feet comprise support pads to substantially spread the load carried and stabilise the supporting structure in use in the assembled configuration.

15. A reusable supporting structure according to any preceding paragraph, comprising locating features configured to accurately position the supporting structure relative to one or more of the building parts.

16. A reusable supporting structure according to paragraph 15, wherein the locating features comprise lower locating features to accurately locate a base of the supporting structure relative to an arrangement of building parts and/or upper locating features to accurately locate an upper region of the supporting structure relative to an arrangement of building parts in the assembled configuration.

17. A reusable supporting structure according to paragraphs 15 or 16, wherein the locating features comprise a plurality of pre-drilled holes and wherein part of the supporting structure is alignable with the pre-drilled holes on the building parts to enable accurate location of the supporting structure in the assembled configuration such that a fixing member may be inserted through each hole to secure the supporting structure to at least one of the building parts.

18. A reuseable supporting structure according to any preceding paragraph, wherein the load bearing cross members comprise a timber portion to support an underside of a building part to substantially spread load carried by the structural support in use in the assembled configuration.

19. An edge protection system to provide a protective barrier along open edges of a building, the edge protection system comprising: a plurality of interconnectable upright and substantially perpendicular barrier members, and locating features to accurately position the safety barrier on part of a building; wherein the edge protection system is detachably connectable to a floor element of a building at a predetermined location using the locating features. 20. An edge protection system according to paragraph 19, wherein the edge protection system comprises a plurality of complementary locating features configured to engage with locating features provided on the building and locate the edge protection system in a predetermined location position on the building.

21 . An edge protection system according to paragraphs 19 or 20, wherein the edge protection system further comprises locking features to securely attach the edge protection system to the building.

22. An edge protection system according to paragraph 20, wherein the locating feature also comprises a locking feature such that coupling of the edge protection system to the building inherently ensures that the edge protection system is locked into position on the building.

23. An edge protection system according to any of paragraphs 19 to 22, wherein the edge protection system is between around 100cm and 160cm in height.

24. An edge protection system according to any of paragraphs 19 to 23, wherein the edge protection system is at least 90cm in height.