Construction system

A construction system for a wall or floor or roof uses a set of studs having panel engagement features protruding from opposed edges of the stud. Panel elements having apertures receive these features so that they protrude through the panel element apertures. Retainers engage the panel engagement features and press against an outside surface of a panel element and towards the studs with a compression force to form a compression joint. There may be rails to form a mesh with the studs, and the panel elements may not be wide enough to abut each other, narrow panel elements providing sufficient structural strength in combination with the compression joints and the studs.

FIELD OF THE INVENTION

The invention relates to construction of buildings.

PRIOR ART DISCUSSION

In recent years there have been many developments in construction systems, particularly modular systems. Such modular systems are very advantageous for many projects, because whole units can be manufactured off site to exact standards in an environment which is much more efficient than on site.

However, where the buildings are modest in size and there can be frequent design changes modular construction may not be suitable.

U.S. Pat. No. 6,481,172 (Porter) describes structural wall panels having studs and insulation, and facings of gypsum or the like secured in place by pins or nails.

The invention is directed towards providing a construction system which allows simpler and more versatile construction of buildings either on site or off site. Another objective is to provide a high structural strength in walls while using materials with good thermal insulation properties, with ease of construction either on site or off site, and/or with less use of materials.

SUMMARY OF THE INVENTION

According to the invention, there is provided a construction system for a wall or floor or roof comprising:a set of studs having side and edge surfaces, at least one of said set of studs comprising panel engagement features protruding from an edge of the stud,panel elements having apertures to receive said features so that the engagement features protrude through the panel element apertures, andretainers for engaging said panel engagement features and pressing against an outside surface of a panel element and towards the studs with a compression force to form a compression joint.

In one embodiment, at least one stud comprises a series of a plurality of panel engagement features along at least one edge. In one embodiment, there is a series of panel engagement features on both opposed sides of at least one stud. In one embodiment, at least one panel engagement feature comprises a portion extending distally from the stud edge and a portion extending laterally, and configured so that the retainer fits within a space bordered by said portions with a tight fit so that said compression force is applied.

In one embodiment, each engagement feature comprises an opposed pair of said portions forming a socket therebetween. In one embodiment, the panel engagement features comprise dovetail sockets.

In one embodiment, the retainer is in the form of a tongue configured for engagement with a friction fit with the panel engagement feature. In one embodiment, the retainer is wedge-shaped, with a narrower leading end.

In one embodiment, the system further comprises braces configured to interconnect a plurality of compression joints.

In one embodiment, at least one brace comprises a plurality of arms each configured to engage a compression joint.

In one embodiment, the system further comprises a soleplate having apertures for receiving ends of the studs and/or a header plate having apertures to receive ends of the studs.

In one embodiment, the sole plate and/or the header plate have apertures and corresponding bridging inserts fitting said apertures, wherein a pair of plates butted at a cut through an aperture may be joined by insertion of said insert across the cut line. In one embodiment, said apertures are shaped to form two opposed dovetail sockets.

In one embodiment, said apertures are configured to form opposed dovetail sockets when cut through at approximately 45° to a longitudinal direction of the plate.

In one embodiment, the system further comprises outer sheets arranged to be fixed to the retainers to form a cavity defined by depth of the retainers.

In one embodiment, at least two panel elements are joined by bridging members each inserted into an aperture formed by opposing recesses on edges of adjoining panel elements to complete a panel. In one embodiment, the recesses have dovetail socket configurations. In one embodiment, the panel elements comprise a series of a plurality of recesses for said joining.

In one embodiment, at least one of said panel elements is configured to form part of a window or door lintel. In one embodiment, at least one of the studs comprises a plurality of layers of wood-based material.

In one embodiment, the system further comprises rails extending across and inter-connecting studs. In one embodiment, the studs are wider than the rails. In one embodiment, the studs are at least 100% wider than the rails. In one embodiment, the studs have inter-engagement features on at least one side edge and the system comprises a set of rails having corresponding inter-engagement features for engaging the stud features to form an inter-meshed grid.

In one embodiment, at least some rails comprise bracing tongues and the panel has slots to receive said bracing tongues. In one embodiment, at least some panels are narrow, not extending to abut adjoining panels.

In one embodiment, the system further comprises a waterproof skin arranged to fit over a panel, the skin having sufficient rigidity to maintain shape of recesses to accommodate the compression joints. In one embodiment, the skin is of aluminium material. In one embodiment, the skin thickness is in the range of 0.2 mm to 0.5 mm. In one embodiment, the skin includes louvres.

In one embodiment, the system further comprises pre-formed insulation floor lower sections arranged for butting together to form a sub-floor and having features for engaging concrete upper floor sections, and the sections are configured to support a wall formed by a construction system of any preceding claim.

In one embodiment, the lower section features comprise grooves to receive corresponding ridges of the upper sections.

In one embodiment, the system comprises an elongate corner member configured to extend vertically to form a corner at adjoining walls, the corner member comprising a vertical corner portion having a configuration to form a corner and orthogonal tongues extending from the corner portion for butting against two walls. In one embodiment, the tongues extend from a single corner of the corner portion.

In one embodiment, the system comprises an elongate eaves member configured to extend along a joint between a wall and a roof, the eaves member comprising a downwardly-depending portion configured to engage a wall and an upper portion configured to engage a roof.

In one embodiment, the upper portion is configured to provide space for a wall plate to rest on the eaves member so that joists can rest on both the wall plate and the eaves member upper portion. In one embodiment, the eaves member is configured to abut ends of joists resting on a wall and terminating over the wall. In one embodiment, the eaves member upper portion extends at an angle of a roof pitch to engage the roof.

We also describe an elongate eaves member configured to extend along a joint between a wall and a roof, the eaves member comprising a downwardly-depending portion configured to engage a wall and an upper portion configured to engage a roof.

The upper portion may be configured to provide space for a wall plate to rest on the eaves member so that joists can rest on both the wall plate and the eaves member upper portion.

The eaves member may be configured to abut ends of joists resting on a wall and terminating over the wall.

The eaves member upper portion may extend at an angle of a roof pitch to engage the roof.

The invention also provides a building whenever constructed using a construction system and/or an eaves member of any embodiment.

We also describe a construction method performed with a system of any embodiment, the method comprising fabricating a structural wall section byaligning the studs parallel to each other,applying a panel element so that the engagement features protrude through thepanel apertures, andengaging the retainers with the panel engagement features with a friction fit so that they press against an outside surface of the panel and towards the studs with a compression force to form a compression joint.

In one embodiment, a panel is applied on both opposed sides of the studs. In one embodiment, the retainers are tapped into engagement with a friction fit.

The method may include mounting at least one brace behind a plurality of retainers so that the brace links the compression joints.

The method may include a further step of engaging ends of the studs in apertures of a sole plate and a wall plate.

The method may include a further step of connecting at least two panel elements alongside edges by inserting bridging inserts into opposed sockets along the panel element side edges.

The method may include a further step of applying an outer sheet by fixing the sheet to retainers so that there is a gap between the sheet and the panel elements set by depth of the retainers.

The method may include a further step of applying a waterproof membrane to the outside surface of a panel element, the membrane having recesses to accommodate the compression joints.

Additional Statements

According to the invention, there is provided a construction system for a wall or floor or roof comprising:a set of studs; andpanels secured to the studs, and optionally:the studs have inter-engagement features on at least one side edge and the system comprises a set of rails having corresponding inter-engagement features for engaging the stud features to form an inter-meshed grid.

The rails may or may not be required for the structural strength required. If not present, bracing strength may be provided partly or wholly by panels secured on one or both sides of the studs.

In one embodiment, the stud and/or the rail inter-engagement features include slots.

In one embodiment, at least one of the studs and rails comprises a plurality of layers of wood-based material.

In one embodiment, the studs are wider than the rails.

In one embodiment, the studs are at least 100% wider than the rails.

In one embodiment, at least one of said set of studs and/or rails comprises panel engagement features protruding from an edge, and the system comprises panels having apertures to receive said features.

In one embodiment, at least one of said sets of studs and/or rails comprises panel engagement features protruding from opposed side edges.

In one embodiment, the panel engagement features comprise dovetail sockets.

In one embodiment, the system panels have apertures arranged so that the panel engagement feature protrude through the panel apertures.

In one embodiment, the system comprises retainers for engaging said panel engagement features and pressing against an outside surface of a panel in a compression joint.

In one embodiment, rails comprise bracing tongues and the panel has slots to receive said bracing tongues.

In one embodiment, the system further comprises a soleplate having apertures for receiving ends of the studs.

In one embodiment, the system further comprises a header plate having apertures to receive ends of the studs.

In one embodiment, the sole plate and/or the header plate have apertures and corresponding inserts fitting said apertures, wherein a pair of plates butted at a cut through an aperture may be joined by insertion of said insert across the cut line.

In one embodiment, said apertures are of general shape forming two opposed dovetail sockets, with two corners facing longitudinally, and two corners facing transversely.

In one embodiment, the system further comprises outer panels arranged to be fixed to the retainers to form a cavity defined by depth of the retainers.

In one embodiment, the system further comprises pre-formed insulation floor lower sections arranged for butting together to form a sub-floor and having features for engaging concrete upper floor sections, and the sections are configured to support a wall formed by a construction system of any preceding claim.

In one embodiment, the lower section features comprise grooves to receive corresponding ridges of the upper sections.

In one embodiment, at least two panels are joined by bridging members each inserted into an aperture formed by opposing recesses on edges of adjoining panels.

In one embodiment, the recesses have dovetail socket configurations.

In one embodiment, at least one of said panels forms part of a window or door lintel.

In one embodiment, the system comprises two walls adjoining at a corner and a vertical corner member having a configuration to form a corner external surface and orthogonal tongues for butting against the two walls.

In one embodiment, the system comprises a wall and a roof, and an elongate eaves member extending along a joint between the wall and the roof, adjoining the wall on one side and adjoining the roof on another side.

In one embodiment, the eaves member abuts ends of joists resting on the wall and terminating over the wall.

In one embodiment, the roof comprises a structural wall portion along rafters or between rafters and adjoining the eaves member.

In another aspect, the invention provides an eaves member of elongate shape and configured to extend along a joint between a wall and a roof, adjoining the wall on one side and adjoining the roof on another side.

In one embodiment, the eaves member is configured to abuts ends of joists resting on the wall and terminating over the wall.

In another aspect, the invention provides a building whenever constructed using a construction system and/or an eaves member of any embodiment.

According to the invention, there is provided a construction system for a wall or floor comprising:a set of studs having inter-engagement features on at least one side edge; anda set of rails having corresponding inter-engagement features for engaging the stud features to form an inter-meshed grid.

In one embodiment, the stud and/or the rail inter-engagement features include slots.

In one embodiment, at least one of the studs and rails comprises a plurality of layers of wood-based material. In one embodiment, the studs are wider than the rails. In one embodiment, the studs are at least 100% wider than the rails.

In one embodiment, at least one of said set of studs and rails comprises panel engagement features protruding from an edge, and the system comprises panels having apertures to receive said features.

In one embodiment, at least one of said sets of studs and rails comprises panel engagement features protruding from opposed side edges. In one embodiment, the panel engagement features comprise dovetail sockets.

In one embodiment, the system panels have apertures arranged so that the panel fits over a grid formed by the studs and rails with the panel engagement feature protruding through the panel apertures. In one embodiment, the system comprises retainers for engaging said panel engagement features and pressing against an outside surface of a panel in a compression joint. In one embodiment, rails comprise bracing tongues and the panel has slots to receive said bracing tongues.

In one embodiment, the system further comprises a soleplate having apertures for receiving ends of the studs.

In one embodiment, the system further comprises a header plate having apertures to receive ends of the studs.

In one embodiment, the sole plate and/or the header plate have apertures and corresponding inserts fitting said apertures, wherein a pair of plates butted at a cut through an aperture may be joined by insertion of said insert across the cut line. In one embodiment, said apertures are of general diamond slope, with two corners facing longitudinally, and two corners facing transversely.

In one embodiment, the system further comprises outer panels arranged to be fixed to the retainers to form a cavity defined by depth of the retainers.

In one embodiment, the system further comprises pre-formed insulation floor lower sections arranged for butting together to form a sub-floor and having features for engaging concrete upper floor sections, and the sections are configured to support a wall formed by a construction system of any preceding claim.

In one embodiment, the lower section features comprise grooves to receive corresponding ridges of the upper sections.

In another aspect, the invention provides a building whenever constructed by a construction system of any embodiment.

The invention also provides a method of constructing a building, the method including forming grids by intermeshing the studs and rails of any embodiment, placing panels against the grids so that the panel fasteners protrude through the panel apertures, and inserting retainers into the panel fasteners so that they press against outside surfaces of the panels.

DESCRIPTION OF THE EMBODIMENTS

Referring toFIGS. 1 to 7a construction system of the invention includes a limited number of standard components for constructing a wall and/or ceiling, and/or a floor. In this specification the term “wall” will be used, however the wall sections or elements manufactured according to the invention may alternatively be used in a floor, a ceiling, or a roof aligned in the rafters direction.

For constructing a wall a desired number of beams, namely studs1and rails20are cut to length. The studs1each comprise of single or multiple layers2of composite wood material in a high-strength laminated arrangement. Each stud1is pre-cut along a first edge to form dovetail sockets5, and along its second edge to form orthogonal slits6and opposed dovetail sockets7directly below. There are preferably a series of panel engagement dovetail sockets5along each edge, and preferably the separation of the dovetail sockets5is in the range of 500 mm to 750 mm, in one embodiment about 600 mm. Also, it is preferred that there be dovetail sockets5and7on both opposed edges of the studs. This achieves, as described below, compression joints on both opposed sides of a wall for optimum load resistance.

Each rail20is pre-cut along its first edge to form a series of slots21matched to the width of the stud1. Along its second edge each rail20has elongate shallow tongues23separated by recesses22.

The various features of the beams are formed in registry so that they can inter-mesh to form a grid of a desired size. As shown particularly inFIGS. 2 and 3the studs1are simply pressed down so that their slits6encompass the rails20and the slots21encompass the studs1. The studs1and the rails20therefore form a grid with an inter-locking joint at every corner. The extent of contact between edge faces of the beams ensures that the grid is particularly strong despite the fact that there are no fasteners or adhesives used. The grid forms the structure of a wall or ceiling, or floor. Insulation, if desired, may be placed within some or all of the spaces within the grid. As shown particularly inFIGS. 4 and 5the grid is then faced on both sides by panels30formed from inter-locking panel elements31. Each compression panel element comprises a series32of dovetail sockets and tongues formed alternately along two opposed side edges. Also, within each panel element31there is a set of apertures35at locations corresponding to intersection points in the grid formed by the studs1and the rails20. Each aperture35comprises a rectangular portion36and a pair of slots37extending from opposed sides of the rectangular portion.

When a compression panel30is placed on the first side of the grid the dovetail sockets5fit through the apertures35, with tongues23and24of the rails20fitting into the slots37of the apertures35.

The same is done on the second side of the grid. A compression panel30is placed so that the second dovetail sockets7and tongues23fit through the apertures35.

As shown inFIG. 5, the panels30form first and second base surfaces of the wall, with the dovetail sockets5and7of the studs1proud of the external surfaces of the panels30.

Retainers50are inserted into the dovetail sockets5, aligned parallel with, and pressing against, the exposed surface of the panel30, as shown inFIGS. 6 and 7. The retainers50and the dovetail sockets5and7form compression joints which press the panels inwardly towards the studs, rails, and insulation. This completes a base structure which may be used for a wall, ceiling, or floor, in which the panels on opposed sides are in compression towards the studs. This achieves excellent structural strength. The retainers50have the shape for a friction fit within the dovetail sockets5and7, so that there is compression force against the external surface of the panel element31.

Each retainer50may in one embodiment be tapered slightly to have a wedge shape with an increasing thickness from its leading edge, to facilitate easy insertion and to ensure good compression arising from the wedge effect. Any such taper is small, for example 1 to 2 mm over a length of 150 to 200 mm. Also, the retainer may have a shoulder or other protrusion about mid-way along its length to prevent insertion beyond that position.

Preferably, plasterboard is applied over the retainers50, providing a thin cavity having the depth of the retainers. The retainers50provide a convenient external surface for nailing of plasterboard or other sheet of material, the depth of the retainers50providing an insulation cavity. Any desired further layers may be applied according to the location of the wall and the building design. For example external insulation slabs may be applied, followed by a cladding providing an external surface.

The system components may be manufactured by for example milling with a CNC machine from engineered timber sheets if the numbers are small, or moulded from composite materials for higher volume production.

Referring toFIG. 8the wall may be built on a soleplate60, with the studs1fitting into apertures61of the soleplate. The soleplate also includes apertures62having an overall diamond shape, with two opposed corners facing longitudinally and the other two facing transversely. This allows the sole plate to be cut at 45° and butted with another to form a joint in which each side of the aperture62acts as a dovetail socket. This is described in more detail below.

Referring toFIG. 9a complete set of components for wall structure construction in one embodiment is illustrated. There are only approximately 10 to 15 types of structural components in total, which can be used in various combinations to tailor the system to the required end use. This allows the builder to construct a building by bringing these simple components, thereby requiring little transport space and avoiding need to lift heavy weights, and allowing accessibility to locations such as the rear of a terraced house to build an extension. Of course, if desired wall elements may be constructed off-site.

A panel element70has:a substrate71, with longitudinal rectangular apertures72to receive dovetail sockets5or7,hybrid apertures73with a wide portion to receive a dovetail socket and an orthogonal narrow portion to receive a bracing tongue of a rail,transverse slots74, also to receive rail bracing tongues.

Left and right side rails80and85have the same features as the rails20and additionally have through holes83for services.

The soleplate60has the apertures61and62as described above. A stud1and a retainer50are also as described above.

An insert51is suited to fit into a pair of half apertures when two lengths of soleplate meet at a joint, either at right angles or in-line, in both cases the cut being made at 45°.FIG. 10shows the in-line and angled joints, both with an insert51strengthening the connection. Similar joints may be made with lengths of rail, as shown inFIG. 11. As is clear fromFIGS. 10 and 11the apertures62are in the form of two opposed dovetail sockets along a diagonal axis. Hence, when the stud60is cut at 45°, the studs are joined by the insert51acting as an integral pair of dovetails which engage in the two opposed dovetail sockets. This is very simple and convenient.

The header and sole plates60may be fabricated from GL28c glulam beams which are also milled through a CNC machine. The components clip together without the requirement for screws, nails or glue (apart from, in some cases, the sole and header plates) using the compression connection provided by the dovetail sockets5and7and the retainers50. The system is based on a 555 mm grid but can be configured to any grid.

Referring toFIGS. 12 and 13the sequence for wall construction is illustrated as follows:(a) Provide studs1.(b) Insert ends of the studs into a sole plate60aperture61at both ground level and ceiling levels. In the top position it may be referred to as a wall plate.(c) Press panels70towards the studs on both sides so that the dovetail sockets5and7extend through their apertures72and73.(d) Slide in the retainers50to complete compression joints with the dovetail sockets5and7. The action of sliding in the retainers50involves a light hammer impact to a certain extent, as they are a tight fit so that they press in against the external surface of the panel. This completes the structural part of the wall section, the combination of the studs and rails together with the pressed-in panels70forming a tight structure with excellent tensile strength. In studies we have found that the load resistance to failure (excessive buckling) per stud1is:Single ply stud: 50 kN,Double ply stud: 65 kN, andTriple ply stud, as illustrated, 75 kNOf course, a panel element with two studs has a load resistance of double these figures. A ground floor level with wall constructed with wall elements having two-ply studs can support up to three storeys for example.(e) Fix plasterboard90to the surfaces of the retainers50. This avoids the problem of nailing into end “grain” of composite wood, as the rails are driven into the retainers50, across the wood grain. It is very simple to affix the outer panels to the wall by fastening to the exposed surfaces of the retainers50, and this provides an insulating gap bridged only by the wood material of the retainers. Such affixing is sufficient because the outer panels90are not load-bearing.(f) Insert polystyrene insulation blocks92and95inside and outside the structure. The insulation92may alternatively be inserted before step (c), when the spaces between the studs are more open and easily accessible.

It will be appreciated that the system provides low-cost construction requiring minimal expertise, having ease of installation and multiple construction applications. The system can be used for permanent on-site builds, prefabricated panels, pre-manufactured modular housing, as well as for emergency accommodation and shelters. Also, the components are very light-weight, have good insulation, and are cost-effective to manufacture. Advantageously, the compression joints in combination with the studs and the panels achieve a very high load resistance. In some instances sufficient load resistance is achieved with none or a small number of rails between the sole plate and the wall plate.

Referring toFIGS. 14(a) and (b)an alternative wall is constructed either on-site or off-site by providing studs1, connecting them to sole plates60top and bottom as described, above, and then pressing a panel element100having openings only for the stud dovetail sockets5. Insulation slabs101are inserted tightly into the gaps between the studs1, and an opposed panel element100is pressed into place with the dovetail sockets7protruding. In this case there are no rails, the only horizontal members being the sole plates60top and bottom. The retainers50are then tapped into place within the dovetail sockets5to complete the compression joints in a regular pattern. A pre-formed membrane skin105having recesses107on a planar base106is applied to achieve sealing from moisture ingress from outside, and then external insulation slab102is applied. There may be other claddings applied as desired.

In this case the absence of rails reduces the number of parts and time of construction, and strength is still sufficient due to the fact that the panel elements100take the vertical loads in combination with the studs1and the compression joints5,50.

In a variation, there may be a small number of one or more rails80placed across the studs to contribute inter-connection of the studs additional to the sole plates and wall plates.

FIG. 15shows a variation in which narrow panel elements120are used, taking the form of strips which do not cover the full surface of the wall element being constructed. External insulation121is applied on the outside, to provide a completed wall element130. The panel elements120still perform the function of compression of the wall element and providing vertical structural strength, but there is less material required.

As shown inFIGS. 16(a) and (b)narrow panel elements120may be used on both opposed sides of the studs, applied in the same manner as for the full-width panel elements70and100. The complete wall element is indicated by the numeral150.

In another variation shown inFIG. 17, the retainers50on at least one side press against cross-shaped braces160which span two panel elements140. Each compression joint therefore applies compressive forces both locally and across three other joints. This helps to ensure uniformity of compression, especially where the panel elements are narrow.

Referring toFIG. 18alternative sealing skins180or190of thin aluminium foil material may be applied to the wall elements to provide a membrane to prevent ingress of moisture from outside. The skin180has a planar portion181and recesses182for accommodating the compression joints50,5. The skin190also a planar portion191, recesses192for the same purpose, and louvres193to allow breathability for release of any moisture from inside while preventing ingress from outside. It is preferred that the skins have a thickness in the range of 0.2 to 0.5 mm, and they may include corrugations (not shown) to achieve sufficient rigidity for ease of handling. They may be of metal such as aluminium or of plastics material.

The membranes180and190are very easy to manipulate as they are rigid enough to be conveniently handled when being put in place and so avoid the problems on-site of handling sheets of light plastics material, which can be easily damaged and blown about if there is any wind.

Referring toFIG. 19the panel elements may be adjoined by insertion of bridging members into apertures formed by two butted panel element edges, akin to the manner described above of adjoining sole plates and wall plates. This drawing shows panel elements300and301, each having edge recesses310which mate together to form a full aperture when two panel elements are butted together. These apertures each have a star-shape, so that when a bridging piece320is inserted it forms a lock by engaging behind panel edge surfaces facing at least partly away from the main edge. This arrangement is shown more clearly inFIG. 20, which shows it for both main wall panels300and for lintel panels350. As is shown more clearly in these drawings, the bridging member352is in the form of a pair of integral dovetails fitting into opposed dovetail slots351.

Referring toFIG. 21, a floor370may be constructed using blocks of foam with pre-set configuration of grooves. These are a variety of foam blocks,371,380,383,381, and382. The foam blocks are arranged to form a floor with a desired shape, such as illustrated at370. Concrete is then poured over the assembled foam blocks. A wall375constructed as described above is mounted on the floor, and there may be an external masonry leaf376. This provides a pre-made foundation slab which by default meets the requirements of a raft foundation. The concrete sections also provide excellent acoustic, fire and thermal insulation between floors.

Referring toFIG. 22a building may have a corner member400inserted to form a corner at two adjoining walls. The corner member400comprises a main body401forming the external part of the corner, and mutually orthogonal tongues402and403which are aligned with and butt against structural wall portions415formed by the studs as shown above. In this example, the walls are completed by an external insulation panel411and an external wall finish layer410, and on the internal side by a services gap formed by plasterboard413secured to the structural wall412.

Referring toFIG. 23a roof may be mounted on walls by placing an eaves member on the wall and forming a joint between the eaves member and the roof structure. InFIG. 23an eaves member501is mounted on a wall formed by a structural wall portion515and external insulation520. The eaves member501comprises a main body502configured to fit on top of the wall, and a downwardly-depending lip503for extending downwardly into the external insulation of the wall. There is a top ridge504which has a height equivalent to a conventional wall plate511.

The eaves member501is placed on the wall515,520with the lip503extending downwardly into the insulation520. The wall plate511is placed on the eaves member main body502alongside the ridge504. Joists516rest on the eaves member501ridge504and the wall plate511and the remainder of the roof is conventional. This provides an excellent seal around the corner at the top of a wall and a roof, which traditionally has been a cold bridge.

FIG. 24shows a building600having an eaves member601having a wall-engaging portion engaging the outer part of the top surface of a wall formed by a structural wall615and external insulation620, and a vaulted roof portion which extends at the angle of the roof to butt against roof panels610made of the same technique as the wall panels110. The roof panels are formed using the studs and possibly also cross-rails as described above for the structural walls of any embodiment. As is clear in this view, there is a complete seal around the corner. The eaves member601has a downwardly-depending portion602for engaging the top of the wall, and an upper sloped portion603which is co-planar with the roof panels610. In this case the eaves member is not load-bearing, but forms a very effective seal across the wall and roof, preventing a common thermal bridging location and hence improving overall insulation characteristics of the building.

Referring toFIG. 25an eaves member701rests on the wall directly at a wall top surface beyond the ends of the joists716. Hence, the joists are terminated on the wall, and do not protrude beyond it, as would be conventional. The eaves member extends upwardly over part of the wall and at an angle of the roof to butt roof members, such as a roof structural panel formed by the studs and optionally also the rails as described above. This forms an envelope for improved insulation around the tops of the walls and, like the eaves member601, is not load-bearing.

The eaves member701has a wall-engaging portion702in the form of a downwardly-depending ridge (engaging wall structural part715and external insulation720), a roof-engaging portion704as forFIG. 24, but also a forwardly-projecting portion703to form a traditional eaves configuration. The joists716rest on only a portion of the wall, and are part of roof frames also including structural panels717and insulation718. Like the eaves member601, the eaves member701is not load-bearing.

It is envisaged that the eaves member may have indents to accommodate the joists, and in this case the joists may rest on the wall to the wall full depth.

Also, any of the eaves members may be used with other wall and/or roof arrangements, such as conventional cavity walls of block for example.

It will be appreciated that the eaves members of the various embodiments provide a thermal break between a wall and a roof in a very effective and simple manner.

Major advantages of the invention include:(a) Simplicity of assembly/construction to achieve wall elements of very high strength.(b) Reduced extent of materials required.(c) Fast and accurate assembly either on-site of off-site.(d) Very high compressive strength provided by the compression joints applying compression forces across the width of the studs. This allows the panel elements to provide structural integrity in combination with the studs, either with or without cross-rails between the sole and wall plates.

In other embodiments, some or all of the structural walls don't have rails forming a mesh with the studs, as the panels secured to the studs provide sufficient bracing strength. It is envisaged that structural walls with rails may be used for some walls, especially deeper walls, and possibly roof panels alongside rafters, and possibly in the foundations. For the latter, it is envisaged that the studs and any rails present may be of a plastics material rather than wood.

In various embodiments, it is not essential that the panel engagement features comprise dovetail sockets. However, in general it is preferred that panel engagement feature comprises a portion extending distally from the stud edge and a portion extending laterally, and configured so that the retainer fits within a space bordered by said portions with a tight fit so that compression force is applied to the panel and stud. It is preferred that the studs stud comprises a series of a plurality of panel engagement features along at least one edge, and most preferably that there is a series of panel engagement features on both opposed sides.

The invention is not limited to the embodiments described but may be varied in construction and detail.