METHOD OF CONSTRUCTING A BUILDING, AND A BUILDING WITH A FRAMEWORK

Abstract

 In a wall of a building comprising structural insulated panels (SIPs) secured to a steel framework, SIPs 800, 802 engage an I-section upright having a web 806 and flanges 808, 810. Adjacent ends of the SIPs 800, 802 abut one another at a joint 812, in line with the mid-section of the web 806. Insulative cores 814, 816 of the SIPs 800, 802 and their structural facings 818, 820 are cut away to form a recess 822 to accommodate the upright 804. Steel plates 824 are secured to the SIPs 800, 802 to close off the recess 822, which is filled with insulative material 828 that bonds with the SIP cores 814, 816. The insulation of the steel upright combats cold bridging, and the recess makes construction of the building easier and cheaper by allowing the SIPs 800, 802 to be moved into place from the side, rather than having to be slid down the height of the upright 804 from above.

Description

[0001] This invention concerns buildings, particularly but not necessarily exclusively buildings for use as domestic dwellings.

[0002] As is well known, domestic dwellings are expensive, notwithstanding repeated calls by campaigners for so-called "affordable housing". Aside from the high cost of land, exacerbated in many places by a shortage of suitable building sites, one of the main reasons for the expense of domestic dwellings is that traditional building methods (especially the use of bricks and mortar) are slow, and dependent upon resources (materials and trade skills) that are themselves expensive and in short supply.

[0003] An alternative to traditional buildings is proposed in US2004/103595 (Glatfelter). This describes a building comprising wall panels, each comprising insulation sandwiched between exterior and interior skins, secured to a ferrous metal framework of I-section members.

[0004] It is an object of the present invention to enable domestic buildings to be constructed more quickly and at lower cost and to shorter build times than those currently conventional and with benefits over previously known framework-and-panels structures like that of Glatfelter. Thus according to a first aspect of the invention there is provided a method of constructing a building comprising the steps of:

(a) forming a foundation which defines a datum level for the building;

(b) constructing on the foundation and securing thereto a framework extending upwards of the datum level, which framework comprises a plurality of mutually spaced-apart framework elements each formed of steel and comprising two flanges interconnected by a web; and

(c) securing between parallel pairs of said framework elements structural insulated panels each having an insulative core sandwiched between structural facings, pairs of said structural insulated panels having adjacent ends abutting one another at a common framework element;

characterised in that said method further comprises configuring the mutually abutting ends of the structural insulated panels to completely cover at least one flange of said common framework element.

[0005] By completely covering at least one flange of the framework element, the steel flange is thermally insulated, and thereby cold bridging through the framework element is combated, as will be discussed in more detail hereinafter. By contrast, Glatfelter's prior art system fails to provide an insulative cover to combat coldbridging through the metal framework.

[0006] Structural insulated panels, commonly known as SIPs, are available from a variety of suppliers including SipsEcopanel of Glenrothes, Scotland. The insulative core typically comprises a foam - or possibly a slab - of styrene or polyurethane (PUR) or polyisocyanurate (PIR), and the structural facings between which the core is sandwiched are typically formed of oriented strand board (OSB) although they may otherwise be of sheet metal, plywood, cement or magnesium oxide board. SIPs are strong, with little or no tendency to shrink or move in use. Importantly, also, they meet national standards for sustainable building as set out for instance in the UK Code for Sustainable Homes and the USA Habitat for Humanity.

[0007] SIPs are available in various sizes up to 6000mm long or more, and can of course be cut to required dimensions, but in Europe at least a common size is 2400mm long by 1200mm (in USA, 8ft by 4ft) and these dimensions can be used as modular spacing for the framework elements of the present invention. It may be noted that around 170 bricks would be required to cover the same area as a 2400mmx1200mm SIP, even as only a single-skin wall, and could take a skilled bricklayer half a day to lay.

[0008] SIPs are also available in various thicknesses, mostly in the range from 100mm to 200mm, and it will be understood that the thickness is related to the profile of the framework elements - so that, for instance, the structural facings of the SIP overlay flanges of the frameworks elements between which it is secured. Commonly, SIPs have an overall thickness of 142mm (USA, 6in) but SIPs of other thickness may be used in the invention.

[0009] The construction of foundations for domestic dwellings is conventionally slow and expensive. Detailed plans have to be prepared in advance before groundwork can begin; and then the depth of excavation must be agreed on site with a building inspector, according to the perceived state of the ground. This can hold up the groundworks timetable, meaning that expensive plant and skilled operatives are used inefficiently and, often, neighbours of the site suffer inconvenience for longer than scheduled. For faster build times, the framework of the present invention - possibly with the SIPs already fitted - can be laid on a foundation of essentially conventional form, with trench/strip footings or concrete rafts/pads, or using screw piling.it is preferred to use screw piling.

[0010] In a second aspect the invention comprises a building comprising a framework formed of a plurality of mutually spaced apart framework elements each formed of steel and comprising two flanges interconnected by a web and, secured between parallel pairs of said framework elements, structural insulated panels each having an insulative core sandwiched between structural facings, pairs of said structural insulated panels having adjacent ends abutting one another at a common framework element; characterised in that, at the mutually abutting ends of the structural insulated panels, the insulative cores of the structural insulated panels are configured to fit closely between the flanges of the common framework element and closely against the web thereof, and the structural facings of the structural insulative panels are configured to fit closely upon and cover at least one said flange of the common framework element.

[0011] Preferably the framework elements are of steel, which is strong and inexpensive. And the SIPs may be used for floors and ceilings, walls and the roof of the building.

[0012] In a third aspect the invention extends to a prefabricated kit of parts for constructing the building.

[0013] Other aspects of the invention will be apparent from the following description, which is made by way of example only with reference to the accompanying drawings which are purely schematic and in which -

Figure 1 is a simplified isometric view of the configuration of a single storey house embodying the invention, as seen from above and the front;

Figure 2 is a simplified isometric view of a screw piled foundation for the house of Figure 1;

Figure 3 is a simplified isometric view of a steel framework for the house of Figure1.

Figure 4 is an isometric view of a front part of the steel framework as at A in Figure 3, to an enlarged scale relative to Figure 2 and illustrating the way in which SIPs are applied to the framework;

Figure 5 is a plan view in cross-section of a corner of the steel framework as at B in Figure 3, to the same scale as Figure 3 and similarly illustrating the way in which SIPs are applied to the framework above a lower ring beam thereof;

Figure 6 is an isometric view corresponding to Figure 5;

Figure 7 is a perspective view illustrating the construction of an upper ring beam of the framework, as at C in Figure 3 and to an enlarged scale;

Figure 8 is an end elevation illustrating the construction of a ridge of the framework in cross-section;

Figure 9 shows an end elevation of framework elements for the roof;

Figures 10 and 11 are perspective views from opposite ends of the roofing framework;

Figures 12 and 13 are perspective views illustrating the construction of the roof;

Figures 14 and 15 are views, in cross-section and viewed from above, of a wall of a house embodying a form of the invention somewhat different from that shown in Figures 1 to 13, Figure 15 showing part of Figure 14 enlarged for clarity;

Figure 16 is a view, partly in cross-section and partly isometric, viewed from above, of a wall of a house embodying a further form of the invention;

Figure 17 is a view, in cross-section and viewed from above, of a wall of a house embodying a preferred form of the invention; and

Figure 18 is a view, in cross-section and viewed from one side, of a floor of a house adapted from the wall arrangement of Figure 17.

[0014] Referring first to Figure 1, the configuration of the house 100 shown therein is simplified in as much as doors, windows and other features are omitted for ease of illustration. The external walls 102 (which may be covered with appropriate cladding, not shown) comprise 2400mmx2400mm SIPs mounted on a steel framework to be described in more detail hereinafter. The internal walls (not shown) also comprise SIPS of smaller dimensions; and in fact, but not shown in Figure 1 for simplicity, the external walls may comprise SIPS 2400mm high by 1200mm wide. Like the walls, the roof comprises SIPs mounted on the steel framework.

[0015] For simplicity of description, the height H of the house 100 to its eaves is a nominal 2400mm, its length L is a nominal 9600mm and its depth D is a nominal 4800mm. Actual houses constructed by means of the invention are expected to be substantially larger than these nominal dimensions, and the house may have two or more storeys, and it does not have to have a simple rectangular footprint.

[0016] Turning to Figure 2, the house 100 has a foundation formed of screw piles 106 with heavy bearer plates driven into the ground at selected locations set using the Global Positioning System (GPS). As illustrated by Figure 2, the screw piles are located just within the planned footprint 108 of the house, spaced apart at 2400mm intervals. There may well be more screw piles than the nominal number shown purely for illustration in Figure 2 (generally they are spaced apart by an amount equal to three or four times the diameter of the pile helix) and they may be arranged differently from those shown in Figure 2, eg to support a house with a non-rectangular footprint.

[0017] The screw piles are driven into the ground by means of rotary hydraulic powerheads to a depth at which it is calculated (in relation to ground conditions) they will support the weight of the house 100. They are then adjusted using a laser so that their tops lie in a common horizontal plane which defines a datum level for the building

[0018] The steel framework 110 of the house 100 comprises, as illustrated by Figure 3, the following framework elements: upright girders (ie columns) of the kind generally designated as universal columns (UC) each having two flanges interconnected by a web; horizontal girders (ie beams) of the kind generally designated as UB and each similarly having two flanges interconnected by a web; and inclined UB beams serving as rafters, ridge beams and other components of the roof. The framework elements are of I-section or C-section according to their function and location in the framework, but it should be understood that details of the sections are not shown in Figure 3, for simplicity of illustration. The framework is mostly bolted together, for strength and longevity, but as noted hereinafter welded connections are used in places.

[0019] The steel framework 110 is coated with zinc phosphate primer.

[0020] As illustrated first of all now by Figure 4, which relates to the part of the framework indicated at A in Figure 3, a SIP 200 (along with other SIPs) is secured in the steel framework, which comprises at its lower end a lower ring beam 202 made from 254x146 UB 37 girder of I-section with a 152x152 U-section column 204 bolted to it by way of a welded end plate 206.

[0021] The SIP 200 comprises an insulative styrene core 208 160mm thick sandwiched between opposed structural facings 210 formed of OSB and each 11mm thick. As indicated at 212, the core 208 is routed or otherwise recessed to lie snugly between the flanges of the column 204 (that is, the flanges extending leftwards as seen in Figure 4). The flanges are spaced apart by an amount (ie 160mm) such that they lie snugly between the overlaying structural facings 210 of the SIP 200, to prevent cold spots and thermal transmission through the assembly. It will be understood that another SIP not shown in Figure 4 is similarly engaged with the flanges of the column 204 that extend rightwards as seen in Figure 4.

[0022] Figure 4 does not show the framework elements of the SIP completely. In practice, both the SIP 200 and the column 204 extend upwards from the ring beam by 2400mm, and the SIP 200, preformed as indicated above, is slid down between two parallel columns with their webs spaced apart so that the SIP fits snugly between them widthwise. The SIP is then secured in position.

[0023] Sections of 254x148 UB girders such as the framework element 202 are joined together around the periphery of the framework 110 to form a complete lower ringbeam 114 as shown in Figure 3. The lower ringbeam 112 is configured and arranged to sit on and be secured to the tops of the screw piles 106 (Figure 2) to support the house 100. SIPs are slid horizontally between lower crossbeams 114 of the framework 110 (Figure 3) - conveniently, while the ringbeam is being constructed - to form a floor for the house 100.

[0024] Figure 5 relates to a corner of the framework 110 as indicated at B in Figure 3. It shows, in cross-section as viewed from above, two SIPs 300 and 302 disposed at right angles to form the corner and engaged respectively with a 152x152 UC 23 I-section corner column 304 and a 150x90x24 PFC C-section column 306 welded to it using 150mm hit 300mm miss stitch welding. Each of the SIPs 300 and 302 has an insulative core 308 of styrene foam sandwiched between OSB structural facings 310.

[0025] The insulative cores 308 are recessed as hereinbefore described to fit snugly between the flanges of their respective steel columns 304 and 306, which flanges are overlaid by the OSB structural facings 310. The space between the flanges of the I-section corner column 304 that does not receive the recessed portion of the SIP core 308 is filled with insulative material 312 similar to that of the cores 308 and the OSB facing is extended as indicated at 314 to cover the material 312 and provide a continuous OSB cover around the steel framework, to counter cold spots and thermal transmission through the structure. Joints, at corners and elsewhere in the OSB can be secured and sealed with an MS-polymer adhesive, which is also used for securing the insulative filling 312 in place.

[0026] For additional clarity, Figure 6 shows the corner at B in perspective, with reference numerals the same as those of Figure 5. It should be noted that the lower ringbeam, which carries the columns 304 and 306, is not shown in Figure 6.

[0027] Figure 7 illustrates the framework 110 as at C in Figure 3. An upper ringbeam 116 (Figure 3) is constructed from sections of 178x102 UB girder 400 secured by M16 8.8 bolts 402 to a plate 404 fillet welded to the top of a column 406, and similarly to other columns of the framework 110. Trusses 118 (Figure 3) interconnect the front and rear parts of the upper ringbeam 116 and are secured to the columns by welding and bolting to provide a moment connection., and whilst the upper ringbeam/truss assembly is being constructed SIPs with their insulative cores recessed as aforedescribed are slid between the flanges thereof to form a ceiling for the house.

[0028] A ridge for the house 100 is constructed as shown in Figure 8. A 178x102 UB 19 ridge beam 500 is secured to the top of a 152x152 UC column 502 having its top end cut and capped with an end plate 504 at an angle to the horizontal, which thereby defines the inclination of the ridge beam 500. SIPs are fitted, in the manner previously described herein, between mutually parallel ridge beams 500, and each such SIP has a solid timber insert at its outer edge to provide or receive a fascia.

[0029] Figure 9 shows framework elements for the roof in end elevation. Front and rear ridge beams in the form of rafters 500f and 500r are each set at a defined inclination and joined together at their apex. At the apex, each ridge beam has a 100mm x 170mm x 8mm end plate 506 secured to it (at an angle to the respective ridge beam so that the end plates are vertically disposed in use) by 6mm fillet welding, and the end plates are then bolted together by way of M18 holes through both the rafters 500f and 500r and press braked. 300mm x 8mm press braked plates form an angled section and are bolted back to form the roof ridge.

[0030] Figure 10 and 11 show other details of the roof structure. At opposite ends of the 4800mm long section shown are pairs of 178x102 UB rafters 500 arranged as in Figures 8 and 9. The apex of the roof is formed of two 2400mm long girders 508 joined together at their proximal ends by way of two 150x150x8 rolled steel angles (RSA) 510 welded together back to back.

[0031] Referring now to Figures 12 and 13, these use the same reference numerals as Figures 10 and 11. SIPs 200 (of which only one is shown in Figures 12 and 13) like those used to form the floor, ceiling and walls of the house 100 are also used to form the roof. They are located between the flanges of the rafters 500, where they are held in place by the vertical webs of the RSA framework elements 510, and they rest on the lateral webs of the RSA framework elements. The assembled roof is covered by cladding such as the Colorcoat Urban (Registered Trade Mark) system supplied by Tata Steel Europe Limited, headquartered in London.

[0032] As described hereinbefore with reference to and as shown in Figure 5, the OSB facing of the SIPs extends to provide a continuous OSB cover around the steel framework, to counter cold spots and thermal transmission through the structure. The arrangement is shown in more detail in Figures 14 and 15, Figure 15 being a relatively enlarged view of the region R of Figure 14. Mutually proximal ends of two SIPs 600 and 602 are engaged with a common framework element in the form of an I-section steel upright having a web 604 and flanges 606 at opposite ends thereof. The insulative cores 608 and 610 of the SIPs 600 and 602 fit snugly against opposite sides of the web 604 and are rebated to receive the flanges 606. The SIPs 600 and 602 have OSB facings 612 and 614 respectively which abut (and may be glued together and/or sealed) on the midline 616 of the web 604. Thus the flanges are completely covered by the OSB and there is no gap whereby cold may reach the common steel upright and be transmitted therethrough.

[0033] Figure 16 illustrates another form of the invention particularly designed to combat cold bridging - which is a matter of great concern to both builders and occupants of buildings.

[0034] The wall shown in Figure 16 includes two SIPs 700 and 702 engaged with a common framework element comprising an I-section steel upright 704 having a web 706 and flanges 708, 710 at opposite ends thereof. Adjacent ends of the SIPs 700 and 702 abut one another at a joint 712, in line with the mid-section of the web 706 of the common steel upright 704. Towards one side of the wall (which is to say, its interior side) both of the insulative cores 714, 716 of the SIPs 700. 702 and their interior OSB facings 718, 720 are cut away to form a recess 722 to accommodate the common steel upright 704. Combining the amount by which each SIP 700, 702 is cut away, the recess 722 has a lateral extent equal to the width of the flange 708, so that the common steel upright 704 is a snug fit therein.

[0035] On the interior side of the wall, the common steel upright 704 extends beyond the thickness of the SIPs 700, 702, and battens 726 having a thickness equal to the inward extension of the steel upright 704 are glued and/or screwed adjacent it, tightly against and level with the flange 710. The battens 724 and similar battens spaced laterally along the SIPs 700, 702 provide support for an inner cladding of plasterboard or the like (not detailed in Figure 16, for simplicity of illustration) with a space behind it for wiring and piping etc.

[0036] Foam material 726 the same as that forming the insulative cores 714, 716 of the SIPs 700, 702 (eg polyurethane) fills the recess 722 and unites with the cores 714, 716 in a cohesive structure. This is done by injecting the filling material from the top of the common steel upright 704; and to make sure the recess 722 is completely filled, the web 706 of the common steel upright 704 may be formed with holes (not shown in Figure 16) allowing for passage of the foam material 726 while it is being injected.

[0037] On the weather side of the wall, the common steel upright 704 is secured in place by fasteners 728 shot-fired through the SIPs 700, 702 and into the flange 708, and the joint 712 is sealed and taped before battens (not shown in Figure 16) are secured to the weather side of the wall to support exterior cladding

[0038] It will be noted that the insulative material of the cores 714, 716 and the filling 726 completely covers at least the flange 708 on the weather side of the common steel upright 704, and thereby combats cold bridging through the wall.

[0039] The arrangement of Figure 16 has another important advantage during construction of a building embodying the invention. This is that the SIPs 700, 702 can be moved orthogonally of the common steel upright 704 to locate the recess 722 on and around the common steel upright 704. Thus the SIPs can be put into place from one side of the wall being constructed, rather than having to be slid down from above, which is awkward and time-consuming. Thus the arrangement of Figure 16 is an improvement upon that described hereinbefore with reference to Figures 1 to 15. And construction in this way is easier and therefore cheaper than prior art arrangements like that of US2004/0103595 which require SIPs to be slid into position down the height of a column.

[0040] Figure 17 is a view similar to that of Figure 16, shown a preferred wall arrangement.

[0041] The wall shown in Figure 17 includes two SIPs 800 and 802 engaged with a common framework element comprising an I-section steel upright 804 having a web 806 and flanges 808, 810 at opposite ends thereof. Adjacent ends of the SIPs 800 and 802 abut one another at a joint 812, in line with the mid-section of the web 806 of the common steel upright 804. Towards one side of the wall (which is to say, its interior side) both of the insulative cores 814, 816 of the SIPs 800. 802 and their interior OSB facings 818, 820 are cut away to form a recess 822 to accommodate the common steel upright 804. Combining the amount by which each SIP 800, 802 is cut away, the recess 822 has a lateral extent equal to the width of the flange 808, so that the common steel upright 804 is a snug fit therein.

[0042] On the interior side of the wall, the steel upright 804 extends beyond the thickness of the SIPs 800, 802, and steel plates 824 disposed laterally of the inwardly extending portion of the web 806 are secured to the SIPs 800, 802 by glued and shot-fired fasteners 826. Thus the plates 824 close off the recess 822, which is then filled with insulative material 828 (eg polyurethane) like and bonding with that of the SIP cores 814, 816, by injecting this from above.

[0043] On the weather side of the wall, the common steel upright 804 is secured in place by fasteners 830 shot-fired through the SIPs 800, 802 and into the flange 808, and the joint 812 is sealed and taped.

[0044] As with the arrangement of Figure 16, battens (not shown in Figure 17) are secured to both sides of the wall to support cladding. And like the arrangement of Figure 16, that of Figure 17 provides benefits in (a) combatting cold bridging, because the common steel upright 804 is covered with insulation on at least its weather side and (b) making construction easier and cheaper by allowing the SIPs 800, 802 to be moved orthogonally into place from the side, rather than having to be slid down the height of the common steel upright 804 from above.

[0045] The arrangement of Figure 18 is an adaptation of that shown in Figure 17, designed particularly for the floor of a building embodying the invention.

[0046] The floor shown in Figure 18 includes two SIPs 900 and 902 engaged with a common horizontal framework element comprising an I-section steel joist 904 having a web 906 and flanges 908, 910 respectively at the top and the bottom of the web 906. Adjacent ends of the SIPs 900 and 902 are cut away to form a recess 912 to accommodate the common steel joist 904, the recess 912 having a lateral extent equal to the width of the top flange 908, so that the common steel joist 904 is a snug fit therein.

[0047] On the underside of the floor, the common steel joist 904 extends below the thickness of the SIPs 900, 902, and steel plates 914 disposed laterally of the downwardly extending portion of the web 906 are secured to the SIPs 900, 902 by glued and shot-fired fasteners 916. Thus the plates 914 close off the recess 912, which is then filled with insulative material 918 (eg polyurethane) like and bonding with that of the SIP cores 920, 922. Rolled steel angles 924 are located on the underside of the plates 914 and against the web 906 of the web 904, and the assembly secured in place by fasteners 926 shot-fired into the SIPs 900, 902.

[0048] It will be noted that the recess 912 allows the SIPs 900. 902 to be conveniently dropped vertically down into place on the horizontal common steel joist 904 to form a floor, rather than having to be slid along the length of the joist 904. On the upper side of the floor, the common steel joist 904 is secured in place by fasteners 928 shot-fired through the SIPs 900, 902 and into the upper flange 908.

[0049] The arrangement of Figure 18 may be adapted to form a ceiling or a roof.

[0050] In the present invention, an arrangement in which the SIPs are formed with recesses to receive the framework members (widthways, not just the flanges of the framework members, as in the embodiments of Figures 16, 17 and 18) is recommended. As well as providing improved protection against cold bridging through an external wall, the recessed configuration is of benefit in internal walls because it is cheaper and more convenient in that it allows the SIPs to be moved sideways into position on the framework (which will be assembled at least in part before the SIPs are installed) rather than having to be slid along the length of a framewrork element, between its flanges. It should also be understood that, whilst Figures 16, 17 and 18 show connections between SIPs and a framework element in a straight section of walling or flooring, the recessed configurations shown therein can be adapted to corner connections (see eg Figures 5 and 6) in which two SIPs at right angles to one another meet at a common framework element, or similarly in roof structures where the SIPs are at an angle to one another rather than being in a straight line.

[0051] Those skilled in the art will now appreciate that the main features of the invention are as follows.

[0052] Floor cross-beams are welded to an array of GPS-positioned screw-bored piles with heavy bearer plates. Each pile is designed and installed to support a load of 10,000kgf, and the building including framework plus SIPs and building fittings weighs about 15,000kgf.

[0053] Deep, heavy-duty I-section girders are used to construct a peripheral ring beam. SIPS having a 160mm thick insulative core of foam (preferably polyurethane but possibly another material such as styrene) sandwiched between two 11mm OSB structural facings are installed between the webs of the cross-beams to form a floor. The floor is covered with particleboard flooring such as the CaberDek (Registered Trade Mark) flooring available from Norbord Europe Limited of South Molton, UK, which flooring has a wear-restant, water-resistant and slip-resistant coating.

[0054] An upper ringbeam is constructed to complete a box-like structure for the steel framework.

[0055] Walls of the building are formed of SIPs 2400mm high and either 1200mm or 2400mm wide, with made-to-measure or cut-to-size end panels. The SIPs completely cover the girders, at least on the weather side, to prevent cold spots, and are themselves enclosed by 25mm cavities and membranes, within inner and outer finishing cladding. The inner cladding may be skimmed plasterboard or, like the outer cladding, to choice. Double-cladding to a total thickness of about 240mm offers U-values better than 0.17W/m2K, exceeding current targets such as the norm of 0.21W/m2K adopted by the European Mineral Wool Manufacturers Association (EURIMA). It also provides good results in airtightness, for passive housing.

[0056] According to customer choice, windows and doors may be sealed double- or triple-glazed units.

[0057] A key aim of the invention is to offer, at an extremely competitive price, a house with a build time of only three to five weeks which is especially suitable for DIY completion. The house as delivered would include basis first-fix facilities for water, sewage and electricity. And it would be ready for purchasers to choose and fit out their own kitchens, bathrooms, and utility areas with appliances. (This has a particular advantage in the self-build market. The house as delivered is adequate for a purchaser to move into it - not into a caravan or tent on site - and complete the house within their own timescale and budget).

[0058] However, whilst the invention is particularly suitable for self-build customers, who can complete it to their own particular requirements and to their own timescale, the "plain vanilla" structure it delivers is likely to be attractive also to developers, local authorities and housing associations

[0059] The invention allows a wide variety in design, even within the modular configurations using standard 2400mmx1200mm SIPS. Beyond that, SIPs of longer length can be used, with no need for jointing; and SIPs can be cut to a required length.

[0060] The building may have a single-pane flat roof or a pitched roof which may be covered by cladding such as the Colorcoat Urban (Registered Trade Mark) system supplied by Tata Steel Europe.

[0061] Finally it will be noted that the formation of recesses in ends of the SIPs facilitates construction by enabling the SIPs to be conveniently put into place from one side (or, in the case of a floor, from above) rather than having to be slid along the length of a framework element as in prior art arrangements.

Claims

1. A method of constructing a building (100) comprising the steps of:

(a) forming a foundation (106) which defines a datum level for the building (100);

(b) constructing on the foundation (106) and securing thereto a framework (110) extending upwards of the datum level, which framework comprises a plurality of mutually spaced-apart framework elements each formed of steel and comprising two flanges (606) interconnected by a web (604); and

(c) securing between parallel pairs of said framework elements structural insulated panels (600, 602) each having an insulative core (608, 610) sandwiched between structural facings (612, 614), pairs of said structural insulated panels (600, 602) having adjacent ends abutting one another at a common framework element;

characterised in that said method further comprises configuring the mutually abutting ends of the structural insulated panels (600, 602) to completely cover at least one flange (606) of said common framework element.

2. A method of constructing a building as claimed in Claim 1 characterised in that said method comprises, at the mutually abutting ends of the structural insulated panels (600, 602), configuring the insulative cores (608, 610) of the structural insulated panels (600, 602) to fit closely between the flanges (606) of the common framework element and closely against the web (604) thereof, and configuring the structural facings (612, 614) of the structural insulative panels (600, 602) to fit closely upon and over said one flange (606) to cover it.

3. A method of constructing a building as claimed in Claim 2 characterised in that said method comprises mutually spacing the framework elements by a modular distance defined by the length and breadth of the structural insulated panels.

4. A method of constructing a building as claimed in any preceding claim characterised in that said method comprises forming said foundation by driving into the ground a plurality of screw piles 106 to a depth at which their tops lie in a common horizontal plane determined by laser levelling.

5. A method of constructing a building as claimed in any preceding claim characterised in that said method comprises the steps of:

a) securing some of the structural insulative panels between said parallel pairs of framework elements vertically disposed so as to form walls of the building;

b) securing some of the structural insulated panels between said parallel pairs of framework elements horizontally disposed so as to form a floor and a ceiling of the building; and

c) securing some of the structural insulated panels between said parallel pairs of framework elements inclined to the horizontal so as to form a roof of the building.

6. A method of constructing a building as claimed in Claim 1 including constructing a wall with an exterior side and an interior side, characterised in that said method comprises the steps of:

a) cutting away adjacent ends of a said pair of structural insulated panels (700, 702) to form a recess (722) configured and arranged to receive said common framework element;

b) moving the structural insulated panels (700, 702) of said pair orthogonally of the common framework element to locate said recess (722) on the exterior flange (606) of the common framework element to cover its exterior side; and

c) filling said recess (722), on the interior side of said exterior flange (606), with insulative material (726) which bonds with the insulative cores (608, 610) of the structural insulated panels (600, 602).

7. A method of constructing a building as claimed in Claim 6 characterised in that said method further comprises securing steel plates (824) to both structural insulated panels (800, 802) of said pair on the interior side of the wall, to close off said recess (822) on the interior side of the wall before it is filled with said insulative material (828).

8. A method of constructing a building as claimed in Claim 1 including constructing a floor of the building with an upper side and a lower side, characterised in that said method comprises the steps of:

a) cutting away adjacent ends of a said pair of structural insulated panels (900, 902) to form a recess (912) configured and arranged to receive said common framework element (904) horizontally disposed;

b) moving the structural insulated panels (900, 902) of said pair vertically downwards onto the common framework element (904) to locate said recess on the upper flange (908) of the common framework element (904) to cover its upper side;

c) filling said recess (912), on the lower side of said upper flange (908), with insulative material (918) which bonds with the insulative cores (920, 922) of the structural insulated panels (900, 902); and

d) securing steel plates (924) to both structural insulated panels (600, 602) of said pair on the lower side of the floor, to close off said recess (912) on the lower side of the floor before it is filled with said insulative material (918).

9. A building comprising a framework formed of a plurality of mutually spaced apart framework elements each formed of steel and comprising two flanges interconnected by a web and, secured between parallel pairs of said framework elements, structural insulated panels each having an insulative core sandwiched between structural facings, pairs of said structural insulated panels (600, 602) having adjacent ends abutting one another at a common framework element; characterised in that, at the mutually abutting ends of the structural insulated panels (600, 602), the insulative cores 608, 610) of the structural insulated panels (600, 602) are configured to fit closely between the flanges (606) of the common framework element and closely against the web (604) thereof, and the structural facings (612, 614) of the structural insulative panels (600, 602) are configured to fit closely upon and cover at least one said flange (606) of the common framework element.

10. A building as claimed in Claim 9 characterised in that insulative cores (608, 610) of the structural insulated panels (600, 602) are recessed to receive flanges (606) of the framework elements, with the cores (608, 610) fitting snugly between the flanges (606) and the structural facings (612, 614) overlaying at least one flange (606).

11. A building as claimed in Claim 9 characterised in that adjacent ends of a said pair of structural insulated panels (700, 702) are formed to provide together a recess (722) configured and arranged to receive said common framework element (704) with an exterior flange (708) thereof against one side of the recess (722), and in that the recess is filled, on the interior side of said exterior flange (708), with insulative material (726) bonded with the insulative cores (714, 716) of the structural insulated panels (600, 602).

12. A method of constructing a building as claimed in Claim 11 characterised in that said building further comprises steel plates (824) secured to both structural insulated panels (800, 802) of said pair on the interior side of the wall and closing off the interior side of said recess (822).

13. A building as claimed in Claim 9 characterised in that said building includes a floor wherein:

a) adjacent ends of a said pair of structural insulated panels are cut away to form together a recess (912) configured and arranged to receive said common framework element (904) horizontally disposed;

b) the structural insulated panels (900, 902) of said pair are located on an upper flange (908) of the common framework element (904) and cover its upper side;

c) said recess (912) is filled, on the lower side of said upper flange (908), with insulative material (918) which bonds with the insulative cores (920, 922) of the structural insulated panels (900, 902); and

d) steel plates (924) are secured to both structural insulated panels (900, 902) of said pair on the lower side of the floor, to close off said recess (912) on the lower side of the floor before it is filled with said insulative material (918).

14. A prefabricated kit of parts for a building as claimed in any of Claims 19 to 13, which kit comprises a plurality of said framework elements configured to form a said framework accommodating a plurality of said structural insulated panels securable to the framework elements to form a floor, interior and exterior walls, a ceiling and a roof of the building.

Drawing