WO2021189156A1 - Systems and methods for constructing a single-storey building - Google Patents

Abstract

Systems and methods of constructing a single-storey building utilizing a plurality of prefabricated insulated panels, each of the plurality of prefabricated insulated panels comprising a first cementitious layer, a second cementitious layer, and an insulative core, wherein the insulative core is disposed between the first and second cementitious layers. The systems and methods comprise constructing a building foundation and constructing the single-storey building on said foundation, the building comprising an exterior wall supported by at least said building foundation using a first plurality of the prefabricated insulated panels, the first plurality of panels forming the exterior wall disposed on an outer perimeter of the building and a roof supported by at least said exterior wall using a second plurality of the prefabricated insulated panels, the second plurality of panels forming the roof enclosing a top of the single-storey building.

Description

SYSTEMS AND METHODS FOR CONSTRUCTING A SINGLE-STOREY BUILDING

Cross-Reference to Related Applications

[0001] This application claims priority from US Application No. 63/001194 filed 27 March 2020 and entitled SYSTEMS AND METHODS FOR CONSTRUCTING A SINGLE-STOREY BUILDING which is hereby incorporated herein by reference for all purposes. For purposes of the United States of America, this application claims the benefit under 35 U.S.C. §119 of US application No. 63/001194 filed 27 March 2020 and entitled SYSTEMS AND METHODS FOR CONSTRUCTING A SINGLE-STOREY BUILDING.

Technical Field

[0002] The invention relates to methods of constructing a single-storey building out of large pre-fabricated panels.

Background

[0003] Many techniques exist for constructing buildings. For some commercial buildings, timber-frame construction remains an option, requiring the erection of timber framing followed by the completion of walls and roofing, including the installation of insulation and utilities. Some commercial and industrial buildings can be constructed from steel frames and metal siding. Pre-fabricated metal frames of steel bents or light trusses enclosed by metal siding are used for some single-storey commercial uses.

[0004] Reinforced concrete is a common building material for many commercial and industrial uses. The materials are frequently cheap and readily available. However, large scale construction with reinforced concrete produces substantial greenhouse emissions, including carbon dioxide. Additionally, cast-in place or in situ construction with reinforced concrete requires allowing time for the setting of the concrete. Longer construction schedules can lead to significantly increased building costs due to cost of labour.

[0005] Another method is to use precast concrete in which sections of buildings are produced as whole concrete segments. However, the use of large volumes of concrete causes significant emissions of greenhouse gases. Additionally, due to the weight of concrete, precast concrete segments impose additional difficulties in their transportation and erection at the construction site.

[0006] There remains a need for practical and cost effective ways to construct buildings such as single-storey residential, commercial and industrial buildings using systems and methods that improve on existing technologies.

[0007] The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.

Summary

[0008] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above- described problems have been reduced or eliminated, while other embodiments are directed to other improvements.

[0009] This invention has a number of aspects. These include, without limitation:

• constructing a single-storey building out of tall prefabricated panels, where individual panels span between foundation/floor and roof panels, in which some of the prefabricated panels comprise cross bracing embedded within an insulative core of the panels;

• constructing a single-storey building out of prefabricated panels with cementitious layers, the prefabricated panels comprising roof panels, exterior wall panels, floor panels and foundation panels, in which some of the different prefabricated panels comprise different cementitious layers;

• constructing a single-storey building out of large and light prefabricated panels including roof panels, exterior wall panels, floor panels and foundation panels, the prefabricated panels comprising thin cementitious layers on each side of an insulative core; and

• constructing roof panels out of prefabricated panels with cementitious layers, which when connected together, form a roof profile having a water drainage channel. [0010] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions.

Brief Description of the Drawings

[0011] Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.

[0012] Figure 1 is a perspective view of a single-storey building comprising a plurality of different prefabricated panels.

[0013] Figure 2 is an exploded view showing combinations of the different prefabricated panels of the Figure 1 embodiment.

[0014] Figure 3 is a cross-sectional elevation view of the single-storey building of the Figure 1 embodiment.

[0015] Figure 4 is a cross-sectional view of a floor panel according to an example embodiment taken along lines A-A of Fig. 3.

[0016] Figure 5A is a perspective view of an exterior panel having cross bracing. Figures 5B and 5D are front and side elevation views of the Figure 5A exterior panel, respectively. Figure 5C is a cross section view on the lines C-C of Figure 5B. Figure 5E is an exploded view of the Figure 5A exterior panel further comprising bottom and top layers of cementitious material.

[0017] Figure 6 is a perspective view of a single-storey building comprising a plurality of different prefabricated panels.

[0018] Figure 7 is a perspective view of an example partial roof assembly for implementing roof water drainage.

[0019] Figure 8 is a perspective view of a single-storey building comprising a plurality of different prefabricated panels.

[0020] Figure 9 is an exploded view showing combinations of the different prefabricated panels of the Figure 8 embodiment.

Description [0021] Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

[0022] Figure 1 is a perspective view of an assembled single-storey building 10 using systems and methods of constructing buildings from prefabricated panels described herein. Figure 2 is a perspective exploded view of single-storey building 10 of the Figure 1 embodiment. As illustrated, building 10 comprises a plurality of different adjoined prefabricated panels forming foundation walls 12, floor 14, exterior walls 16 and roof 18. Single-storey building 10 may be suitable for use as a commercial building, such as a fast food restaurant or a retail store, a single-family home, or the like.

[0023] According to a preferred embodiment of the invention, the prefabricated panels used herein may be similar to panels described in detail in Canadian Patent No. 2,994,868 issued on April 2, 2019 entitled PREFABRICATED INSULATED BUILDING PANEL WITH CURED CEMENTITIOUS LAYER BONDED TO INSULATION, which is hereby incorporated by reference in its entirety. Prefabricated panels described in Canadian Patent No. 2,994,868 comprise an insulative foam core covered on inner and outer surfaces with a composite cementitious layer. Different cementitious materials which make up the cementitious layers may have different performance characteristics and material properties. For example, some cementitious materials used may feature higher fire protection and/or sound dampening, while other cementitious materials may have higher structural support characteristics.

These different properties may advantageously be used for obtaining desirable characteristics specific to the function performed by each of foundation walls 12, floor 14, exterior walls 16 and roof 18 or by any other prefabricated walls or panels described herein.

[0024] In some embodiments, prefabricated insulated panels used herein comprise cementitious material layers having a lower density cementitious material containing perlite, which provides stronger fire resistance properties. As an illustrative example, under the ULC-S101 fire resistance testing standard employed in Canada, prefabricated panels used herein may have a fire resistance rating in the range of 45 minutes to 4 or more hours from the inside, outside, or both. [0025] It is advantageous that certain ones of the prefabricated panels used in the present invention comprise a greater fire resistance construction than those of other prefabricated panels. For example, prefabricated panels used for the construction of exterior walls 16 preferably do not comprise any combustible material or material which may melt under certain fire conditions. In some embodiments, prefabricated panels used for the construction of exterior walls 16 comprise a mineral wool insulative core. Prefabricated panels fabricated from non-combustible materials may be referred to herein as “fire walls”. For exterior walls 16 situated on zero-lot-lines, it may be advantageous to employ fire walls having a higher fire resistance rating in the range of 2 to 4 hours to ensure that fires which may occur are not spread to adjacent properties. Fire walls may be employed for other walls (including interior walls) in the present invention where it is important in the circumstances to prevent the spread of fire or to be in compliance with building regulations and codes, such as for a fire-proof enclosure of a boiler room.

[0026] Figure 3 shows a cross-sectional elevation view of an exemplary single-storey building 10. Foundation walls 12 are depicted as extending into ground 11 , with a portion of foundation walls 12 extending above the surface of ground 11 . As illustrated, foundation walls 12 may rest on top of and be supported by a foundation 15. In some embodiments, foundation 15 is a spread footing foundation wherein the foundation has a wider bottom portion than the load-bearing foundation walls it supports, the wider portion distributing the weight of building 10 over a greater area. In some embodiments, foundation 15 comprises cast in place concrete. In other embodiments, foundation 15 comprises precast concrete which is cured in a plant and transported to the construction site for installation.

[0027] According to another example embodiment, building 10 has no below grade foundation walls. Rather, shallow footing foundations (not shown) may be used to support a floating monolithic slab (not shown) on or slightly below grade. In such embodiments, foundation walls 12 are not present in building 10 and the exterior walls 16 rest on either the floating slab or on the shallow footing or both, either of which may serve as building 10’s foundation. In an alternative embodiment, only a floating slab is provided for serving as the foundation of building 10. The floating slab may additionally optionally serve as the interior floor of building 10. In some embodiments, the shallow footing foundation and/or the floating slab comprises cast in place concrete. In other embodiments, the shallow footing foundation and/or the floating slab comprises precast concrete which is cured in a plant and transported to the construction site for installation.

[0028] Foundation walls 12 comprise a plurality of adjoined prefabricated foundation panels 22, a number of which are shown in Figure 2. Foundation walls 12 should have sufficient compressive load bearing capacity to carry the weight of building 10 above as well as to support additional live and dead loads based on the specific application of building 10 and as required by relevant building codes. Foundation walls 12 should additionally have sufficient transverse and shear load bearing capacity, where such forces may be imposed from the effects of expanding soil in ground 11 and from seismic activity.

[0029] There are several possible options in configuring foundation panels 22 for imparting the strong structural strength required by walls 12, which may be pursued individually or in combination with one another. In some embodiments, prefabricated panels used for foundation panels 22 comprise one or more metal reinforcing bars (not shown) embedded within the cementitious layer along the vertical length of the panel for providing additional structural strength. The metal reinforcing bars may be embedded in an inner layer of cementitious material facing the interior of building or in an outer layer of cementitious material or both.

[0030] The metal reinforcing bars may be disposed and spaced apart along a horizontal direction of panels 22 and may also be disposed and spaced apart along a thickness of the cementitious layer(s) and/or the insulative core. In some embodiments, cross braces comprising metal reinforcing bars are disposed within the cementitious layer(s) of the prefabricated panel forming foundation panels 22.

[0031] In some embodiments, the axial load bearing capacity of panels 22 may be further increased by embedding one or more structural elements along a vertical length of the insulative core of each of panels 22. In some embodiments, the structural elements comprise hollow structural section (HSS) steel frames (not shown). In some embodiments, corresponding vertical ends of HSS steel frames disposed at each respective horizontal end of a foundation panel 22 are connected to one another through horizontally oriented steel frames to form a rectangular-shaped frame. In some embodiments, the HSS steel frame is bonded to the insulative core by a cured cementitious casting. According to a specific embodiment, adjacent foundation panels 22 are joined together by corresponding splines located on HSS steel frames disposed along the exterior vertically oriented edges of each panel 22. Other means for connecting adjacent foundation panels 22 are possible, such as through the use of fasteners, adhesives, welding processes and the like.

[0032] Foundation panels 22 may experience lateral pressures acting perpendicularly against the exterior-facing surfaces due to back fill tendencies resulting from the excavated soil. In some embodiments, foundation panels 22 comprise a thickened interior and/or exterior composite cementitious layer as compared to prefabricated panels used in other applications described herein, which helps to increase the strength of panels 22 to oppose lateral pressures. Optionally, a greater number and/or a greater thickness of metal reinforcing bars are disposed within the thickened cementitious layers. The addition and inclusion of structural reinforcement features and enhancements described herein may advantageously be utilized for achieving desired structural load requirements.

[0033] Furthermore, it is preferable that foundation walls 12 are resistant to shear forces stemming from seismic events, which imparts forces in direction co-planar to the interior and exterior-facing surfaces of foundation walls 12. In some embodiments, the cementitious layer of foundation panels 22 or a portion thereof may be formed from a lower density material. The lower density material imparts higher ductility which results in panels 22, and therefore foundation walls 12, to be more resistant to forces in the co-planar direction.

[0034] Building 10 may comprise a crawl space or basement 20 by extending foundation walls 12 sufficiently deep into ground 11 , best shown by Figure 3. Basement 20 is defined as the space enclosed by foundation 15, foundation walls 12, and floor 14. Basement 20 may serve as a residential dwelling and/or serve as an area where plumbing, electrical wiring, insulation and heating, and cooling systems for building 10 are disposed. In some embodiments, basement 20 serves as a commercial kitchen, a walk-in commercial freezer, or both.

[0035] Floors 14 comprise a plurality of adjoined prefabricated floor panels 24, a number of which are shown in Figure 2. Floor panels 24 comprise an insulative core covered on top and bottom surfaces in a composite cementitious layer. Floor panels 24 are designed such that the span of floor panels 24 between its supports is appropriate for bearing expected loads experienced thereon. In some embodiments, floor panels 24 have a total thickness in the range of 6 inches to 36 inches. In typical applications, floor panels 24 have a total thickness in the range of 12 inches to 24 inches.

[0036] As an illustrative example and with reference to Figure 2, floor 14 has an outer perimeter that is slightly smaller than and corresponds to an inner perimeter of foundation walls 12. An area 12-1 is provided on the inner perimeter of foundation walls 12, illustrated in Figure 2 as the area defined by the illustrated dotted line to the top surface of walls 12.

An outer side edge 14-1 of floors 14 may be configured to attach to area 12-1 using any appropriate connectors. By connecting floors 14 to foundation walls 12 in this manner, the top face of floors 14 may be flush with the top edge of foundation walls 12 and be adjacent an interior bottom edge of exterior walls 16. However, this is not necessary and floors 14 may rest on top of foundation walls 12 and subsequently support exterior walls 16 in other embodiments of this invention.

[0037] In the illustrated example embodiment, floor panel 24-1 has a span S. Based on the measurement of span S, the maximum bending moment and deflection based on expected loads on floor panel 24-1 can be measured. Floor panel 24-1 should therefore be designed to support this expected load whilst considering a relevant safety factor. In some embodiments, span S may be 24 feet. In other embodiments, span S may be 32 feet or more.

[0038] At larger values of span S, the vibration and deflection of floor panels 24 becomes an issue. Generally, weight may be added to floor panels 24 to dampen vibration. This may be achieved by making the cementitious layers thicker and/or by forming the cementitious layers from a higher density material. In some embodiments, weight is added to panels 24 by applying an additional layer of cementitious material or soundproofing material or both as an overlay or underlay. However, adding excessive weight to floor panels 24 becomes a problem for shipping panels 24 to the construction site and for adding to the overall weight of building 10. In some embodiments, an internal structural frame may be embedded within the insulative core of floor panels 24 to provide greater resistance to shear loads. In some embodiments, the structural frame comprises pretensioned or prestressed joists. In other embodiments, the structural frame comprises an HSS steel frame.

[0039] Advantageously, the composite cementitious layers help to obtain a higher stiffness of floor panels 24 and floor 14 compared to conventional floors. In this manner, a larger span S may be accommodated while maintaining a lower weight of floor panels 24 because of the use of thinner layers of cementitious material. According to an example embodiment, a floor panel 24 may have a total thickness of 28 inches (extending in the vertical direction of building 10), the floor panel 24 comprising an internal structural frame having a thickness of 20 inches embedded within an insulative core having a thickness of 26 inches and covered on top and bottom surfaces by 1 inch of cementitious material. Different embodiments of floor panels 24 or any other prefabricated panels discussed herein may have different thicknesses for each of the constituent components depending on the desired application. Relevant factors which may influence this choice include, but are not limited to, a span/length measurement, load bearing conditions (such as a cantilevered portion of floor 14), a desired load rating, and a desired insulation value.

[0040] In some embodiments, water pipes (40A in Fig. 4) are embedded within the insulative core of floor panels 24 wherein flowing water pumped through the pipes stiffen and dampen floor panels 24, allowing for a greater span S. A reservoir (not shown) stored underneath building 10 and a suitable plumbing system may circulate the water to equipment within building 10 in such an embodiment. Advantageously, in the summer, water contained in the reservoir and water pumped through building 10 is heated by the hot weather. This heated water may then be used in winter to provide heating through the pipes embedded in floor panels 24. Any means of implementing a radiant heating system known in the art may be appropriately implemented in buildings and prefabricated panels of the current invention. Water pipes may be embedded in floor panels 24 and/or floor 14 in a number of possible configurations, such as a single/double serpentine pattern or a spiral pattern.

[0041] In some embodiments, water pipes installed within and running through the insulative core of floor panels 24 are in communication with the upper and/or lower cementitious layers so that heat can be transmitted to the floor surfaces (illustrated in Figure 4). In an example open loop radiant heating system, water for supplying the heated water can be sourced from a geothermal heat pump (not shown). In an example closed loop radiant heating system, a water boiler disposed within building 10 heats the water to be circulated through the water pipes.

[0042] The water pipes may run continuously between floor panels 24 by way of junctions or openings defined in floor panels 24 at any appropriate location, for example, mid span, at the longitudinal ends and/or at the corners. In some embodiments, junctions (not shown) are defined on an upper surface of floor panels 24 through an opening in the cementitious layer to interface with a corresponding junction or opening in exterior wall panels 26.

Exterior wall panels 26 may similarly comprise appropriately located junctions or openings to accommodate any appropriate configuration or pattern of water pipes. In such embodiments, radiant wall heating may be provided within building 10.

[0043] Figure 4 is a schematic cross section view through a floor panel 24 of floor 14 in the plane indicated by A-A in Figure 3 according to an example embodiment. In the illustrated embodiment, floor panel 24 comprises a lower cementitious layer 32A, an upper cementitious layer 32B, and an insulative core 34 disposed between lower and upper cementitious layers 32A and 32B. Supporting joist structures 36 are disposed along at least a partial longitudinal length of floor panel 24 within the insulative core 34. Preferably, joists 36 are located at or near the opposite ends of the width of floor panels 24, although this is not necessary. According to another example embodiment, only one joist 36 is provided and is disposed along a substantial length of panel 24 away from the width edges of panel 24.

[0044] In the illustrated embodiment, joists 36 have an I-beam shaped cross section, although other cross sectional shapes are possible. For example, joists 36 may comprise a length of HSS tubing or a plurality of rebar, post-tensioned cables, and/or pre-tensioned cables. In the illustrated embodiment, joists 36 only span a portion of the total thickness of the insulative core 34 which advantageously avoids the creation of a thermal bridge across floor panel 24. In other embodiments, joists 36 span the entire thickness of insulative core 34. In some embodiments, joists 36 are constructed from a reinforced steel material. According to a more specific embodiment, joists 36 are constructed from steel comprising a desired cross-sectional shape which is reinforced with a layer of cementitious material. The cementitious material may additionally comprise an embedded welded wire mesh for providing further reinforcement. Providing joists 36 advantageously permits floor panel 24 to better carry bending and shear loads imposed by loads on top of floors 14 within building 10.

[0045] Figure 4 additionally illustrates a hollow opening 38 along a longitudinal length of floor panel 24 defined within the insulative core 34. Any number of conduits 40 may be provided and be appropriately supported within opening 38. In the illustrated embodiment, conduit 40A comprises a water pipe, conduit 40B comprises an electrical conduit comprising a plurality of electrical wires, and conduit 40C comprises a pipe for plumbing applications. Water pipe 40A is shown to be in communication with upper cementitious layer 32B so that heat can be transmitted to the floor surface of building 10 through upper layer 32B. Mechanical chases or any other appropriate exits (not shown) may be provided on exterior surfaces of floor panel 24 through upper cementitious layer 32B, lower cementitious layer 32A and/or outer faces of insulative core 34 for passing conduits 40 and/or the contents thereof into the interior of building 10, into exterior walls 16, or into basement 20. For example, electrical wiring may be run through the insulative core 34 of panels 24 which connects to electrical systems within basement 20 connecting to a local power distribution substation. In some embodiments, opening 38 spans the entire longitudinal length of floor panel 24, or span S, for fulfilling this function.

[0046] Exterior walls 16 are disposed about and define an above-ground outer perimeter of build 10. It is preferred that exterior walls 16 are load-bearing. Therefore, it is desirable for the exterior panels 26 which collectively form exterior walls 16 to be formed from prefabricated panels which have a high capacity for bearing compressive loads. Exterior panels 26 and exterior walls 16 may share many of the features and design considerations of foundation panels 22 and foundation walls 12 described above. For example, to better bear compressive loads, exterior panels 26 may comprise metal reinforcing bars disposed within its cementitious layers and may feature a greater thickness of cementitious material.

In some embodiments, the structural cementitious layers and/or the insulative core comprise pretensioned or prestressed joists. In some embodiments, supporting joist structures similar to joists 36 described herein in relation to floor panels 24 may be provided in exterior panels 26.

[0047] Additionally, it is preferred that exterior panels 26 and exterior walls 16 have strong thermal insulation properties and are impermeable to moisture, for example from exposure to rain and humidity, in ensuring that building 10 is made weather-resistant. The insulative strength of exterior panels 26 may be augmented through the use of a thicker insulative core and by avoiding the creation of thermal bridges, for example. Resistance to moisture may be achieved by providing a cementitious layer that has a higher density. Additionally, by providing internal channels at the interface of the outer, exterior-facing cementitious layer and the insulative material, exterior walls 12 are able to equalize pressure and to drain moisture which has penetrated the outer cementitious layer. [0048] In some embodiments electrical wiring may be run through the insulative core of panels 26. In some embodiments, the electrical wiring terminates at outlet boxes (not shown) disposed on an interior face of exterior panels 26. Other building components may be disposed within the insulative core of panels 26, with appropriate interfaces defined on inner/outer and perimeter surfaces of panels 26, foundation panels 22, floor panels 24, and/or roof panels 28. Example building components include, but are not limited to, air ducts, electrical wires, conduits, plumbing including hot and cold-water lines, heating pipes, drainage pipes, sewage pipes, vents, gas lines, and teck cables.

[0049] Exterior panels 26 may be constructed to have a height that is substantially longer than its width, in order to accommodate building single-storey buildings with a desirably high roof. In the illustrated embodiment, exterior panels 26 have a height spanning substantially the height of building 10 which is above soil 11 . In some embodiments, exterior panels 26 have a height to width ratio of 2.5:1 to 3:1 or more. Such configurations wherein the height of panels 26 significantly exceeds its width imparts a greater need for enduring shear stresses imposed by wind, these forces generally being transverse to the exterior facing surface of walls 16.

[0050] In other embodiments, exterior panels 26 are constructed to have a width that is substantially greater than its height. Such embodiments may be desirable in single-storey buildings constructed for the purpose of providing a residential dwelling, for example. In such embodiments, exterior panels 26 may have a width to height ratio of 2.5:1 to 3:1 or more. Exterior panels 26 may be constructed to any possible height to width ratios for achieving desired particular functional, structural, and/or aesthetic purposes, such as height to width ratios of 0.5:1 , 2/3:1 , 1 :1 , 1 .5:1 and 2:1 . It is also possible that different ones of exterior panels 26 in a building 10 comprise different height to width ratios.

[0051] Similar to foundation panels 22, structural elements may be embedded along a vertical length of the insulative core at the opposite ends of each of panels 26. Corresponding vertical ends of the structural elements may be connected to one another through horizontally oriented structural framing members to form a rectangular-shaped frame around the perimeter of exterior panel 26. In some embodiments, cross bracing between the vertical structural frames is embedded within the insulative core. Applying a system of cross bracing to exterior panels 26 advantageously imparts high structural shear resilience by allowing panels 26 to support both tensile and compressive forces imposed by shear loads resulting from wind and seismic activity. In other embodiments, corner bracing or knee bracing is employed to impart shear resilience to exterior panels 26.

[0052] Figure 5A is a perspective view of select portions of an example exterior wall 26 comprising cross bracing. Exterior wall 26 in the Figure 5A embodiment comprises a frame 42, which is illustrated as an HSS steel frame, disposed along the perimeter of panel 26 and is seated in a corresponding depression 44, which is defined by a groove or cutout in an insulative core 34. An internal cross brace 46 is rigidly connected to and is supported by each of the four corners of the frame 42 in a diagonal manner such that each individual support 46A, 46B, 46C and 46D of cross brace 46 meet at an equidistant point from each of the corners in the center of cross brace 46 to form a substantially X shape.

[0053] In some embodiments, cross brace 46 and frame 42 each have a thickness that results in an end of cross brace 46 and frame 42 to be substantially flush with an undepressed surface of insulative core 34 when brace 46 and frame 42 are seated in depression 44 of insulative core 34 (this is illustrated in Figure 5C with respect to frame 42 and core 34). In other embodiments, cross brace 46 and frame 42 each have a thickness that results in an end of brace 46 and/or frame 42 to protrude or recede from an undepressed surface of insulative core 34. Either end of exterior wall 26 may face interiorly or exterior of building 10, that is, the surface opposite of depression 44 and the surface most proximate to where frame 42 and cross brace 46 are located.

[0054] In some embodiments, individual supports 46A, 46B, 46C and 46D are integrally constructed from a single piece of material. Cross brace 46 may be formed integrally with frame 42 or cross brace 46 may be attached to frame 42 in any appropriate manner, such as through the use of suitable fasteners, welding, etc. In some embodiments, two separate diagonal supports, for example, combinations of supports 46A, 46C and 46B, 46D, are attached together by an appropriate rigid connection, for example, through welding or through a rigid coupling, in order to form cross brace 46. A number of possible materials are possible for constructing cross brace 46. Possible materials or structures used for constructing cross brace 46 include, but are not limited to, wooden beams, metal reinforcing bars, HSS steel frames, and pre-tensioned steel cables. In some embodiments, multiple cross braces 46 are disposed within prefabricated panels of the present invention. For example, two cross braces 46 may be present in a single prefabricated panel, each cross brace 46 occupying approximately half of the height of the panel. Other configurations are possible, such as where three cross braces 46 are provided in a single prefabricated panel, each cross brace 46 having a different height measurement.

[0055] Figures 5B-5D show additional views of the example exterior wall 26 of the Figure 5A embodiment. Figure 5B illustrates an example chase 48 that may be provided to allow ducts, pipes, wire bundles and such to pass from the interior of building 10 into the interior of panels 26. Figure 5C is a cross-section view through exterior wall 26 in the plane indicated by C-C in Figure 5B. It is not necessary that depression 44 has a uniform depth within insulative core 34, and may be “tiered” at several depths, as illustrated in Figures 5B and 5C. By having a tiered depression 44 in the example Figure 5C embodiment, cross brace 46 is more securely seated within insulative core 34 and can accordingly provide greater structural resilience to exterior wall panel 26.

[0056] Figure 5E is an exploded view of exterior wall panel 26 further comprising bottom and top layers of cementitious material 52A and 52B, respectively. In the illustrated embodiment, a planar bottom layer of cementitious material 52A is coupled to a bottom surface of insulative core 34 when panel 26 is assembled. A top layer of cementitious material 52B is coupled to insulative core 34, frame 42, and/or cross brace 46 when panel 26 is assembled. The bottom and top layers 52A and 52B of exterior wall panel 26 serve as interior and exterior facing surfaces of panel 26, respectively, or vice versa, when assembled in a building 10.

[0057] In some embodiments, cross brace 46 and frame 42 are bonded to a cementitious casting once the cementitious casting has cured. The cementitious casting simultaneously bonds to insulative core 34 to thereby form the layer of cementitious material 52B over top of both insulative core 34, cross brace 46, and frame 42. This example embodiment advantageously provides a method of assembling prefrabricated panels 26 having increased resilience to lateral forces to better withstand forces due to winds and earthquakes. In other embodiments, top layer 52B comprises a layer of structural board such as sheet metal, plywood, magnesium oxide board, or oriented strand board. Top layer 52B may be applied over top of and be coupled to insulative core 34, cross brace 46, and/or frame 42 through any appropriate means, such as through the use of adhesives, fasteners, or the like. [0058] Although the present example describes the use of cross bracing in relation to exterior walls 26, it will be understood by one skilled in the art that the cross bracing techniques described above may advantageously be employed to impart increased lateral force resistance to other prefabricated panels described herein and to prefabricated panels constructed from composite materials in general.

[0059] Figure 6 shows a building 100 comprising a plurality of openings according to an example embodiment of the invention. Exterior panels 26 may comprise openings which define various features such as windows or doors (illustrated in exterior panels 26A and 26B, respectively). In some embodiments, window openings are cast into the cementitious layer of panels 26 with an appropriate mold to form drip edges and sloped window sills. To avoid introducing any thermal bridges, which may diminish the insulative capabilities of exterior walls 16, it is preferred that inner and outer cementitious layers of exterior panels 26 do not come in contact with one another.

[0060] The use of certain materials for the insulative core of prefabricated panels described herein can advantageously provide a thermal break to better provide the insulative capabilities of building 10. Examples of such materials include but are not limited to rigid mineral wool, expanded polystyrene, fiberglass, and neoprene. Additionally or alternatively, the cementitious layer may also serve to provide a degree of thermal breaking. This can be achieved, for example, by employing low-density cementitious materials having high air content and/or by the inclusion of additives such as ceramic bead or perlite.

[0061] In a typical scenario, individual exterior panels 26 are placed on top of and are connected to a corresponding panel 22 of foundation walls 12. In this manner, any loads borne by exterior walls 16, including the weight of exterior walls 16 themselves, are supported by and transferred to foundation walls 12 which are in turn transferred to foundation 15. However, some embodiments of the present invention provide for exterior panels 26C which are supported by other exterior panels 26. In the illustrated Figure 6 embodiment, exterior panel 26C is attached at opposite ends of its horizontal longitudinal length to opposed side edges of exterior panels 26D and 26E. The edges of panels 26C, 26D, 26E, 22A and 22B collectively define an opening 35. As illustrated, exterior panel 26C features a length which is greater in the horizontal direction than that of the vertical direction, although this is not necessary. Example applications for which opening 35 may be used include doorways, window walls, garage doors, and entry ways. [0062] Roof 18 comprises a plurality of adjoined prefabricated roof panels 28, a number of which are shown in Figure 2. In some embodiments, mechanical chases are defined in roof panels 28 which allow ducts, pipes, wire bundles and such to pass from the interior of building 10 into the interior of roof panels 28. For example, electrical wiring may be run through the insulative core of panels 28 which connects to a ceiling lighting box for illuminating the interior of building 10. In some embodiments, supporting joist structures similar to joists 36 described herein in relation to floor panels 24 may be provided in roof panels 28. This advantageously permits roof panels 28 to better carry bending and shear loads.

[0063] It is preferable that roof panels 28 and roof 18 feature strong thermal insulation properties and are impermeable to moisture resulting from precipitation. As previously discussed herein, strong thermal insulation properties may be achieved by the use of a thicker insulative core and by avoiding the creation of thermal bridges. As previously discussed herein, impermeability to moisture may be provided by providing cementitious layers in roof panels 28 that have a higher density and by providing internal channels at the interface of the outer cementitious layer and the insulative core to allow drainage.

[0064] Water buildup due to rainfall or “ponding”, can be detrimental to roof assemblies, causing degradation of the roofing materials, and accordingly should be avoided. A drainage channel defined by a surface profile of roof 18 can advantageously collect water present on the roof 18 and divert the water to another location in order to mitigate water leakage through roof 18 and into building 10. Different ones of roof panels 28 may comprise a variety of shapes and profiles and features that, when attached together to form roof 18, define a means for diverting water off roof 18. In some embodiments, roof 18 comprises a pitched roof having a sufficient downward slope to adequately drain water present on roof 18. In other embodiments, roof 18 comprises a substantially flat roof comprising a drainage channel. It is also possible that roof 18 comprises one or more pitched portions and one or more flat portions comprising drainage channels. The addition of roof features such as inner drains connecting to pipes for draining water are also possible, which may be used alone or in combination with other water diversion methods described herein.

[0065] Figure 7 is a perspective view of an example partial roof assembly 50 for implementing water drainage for roof 18. Partial roof assembly 50 comprises two adjacent prefabricated roof panels 28A and 28B. In the illustrated embodiment, roof panels 28A and 28B taper downwards toward the right and then further downwards away from the junction of panels 28A and 28B. In this manner, a saddle point 55 is created wherein water present on partial roof assembly 50 generally runs downwards (to the right in the Figure 7 example) toward saddle point 55 and again downwards off partial roof assembly 50 at points 57A and 57B.

[0066] As illustrated in Figure 7, the thickness of insulative cores 54A and 54B of roof panels 28A and 28B are appropriately tapered to provide the desired sloping profile of partial roof assembly 50. In other embodiments, the thickness of the cementitious layers 62A and 62B are tapered. In other embodiments, a separate roof membrane having a desired sloping profile may be applied over top of panels 28A and 28B. It will be appreciated that partial roof assembly 50 illustrates only one portion of a complete building roof and that a corresponding roof assembly mirroring that of assembly 50 may be provided adjacent the rightmost surface of assembly 50. In some embodiments, roof 18 of the present invention comprises a hyperbolic paraboloid saddle profile. Any possible means for implementing appropriate drainage means for roof 18 are possible. Further, the methods described herein for providing a drainage channel may be adapted to buildings having any variety of different roof and building configurations.

[0067] Using the prefabricated panels described herein various architectural features can be achieved when constructing building 10. As an illustrative example and with reference to Figure 2, an area 16-1 is provided on the inner perimeter of exterior walls 16, illustrated in Figure 2 as the area between the dotted lines near a top end of walls 16. An outer side edge 18-1 of roof 18 may be configured to attach to area 16-1 using any appropriate connectors. By connecting roof 18 to exterior walls 16 in this manner, a top portion or parapet 16-2 of walls 16 extends upwardly from the envelope defined by building 10 (see Figure 1). As an example, parapet 16-2 may be designed and/or appropriately coated to serve an aesthetic function, to shield roof 18 from high winds, or to provide a safety barrier for individuals on top of roof 18, amongst other possible uses.

[0068] Also with reference to Figures 1 and 2, an overhung portion or eave 18-2 of roof 18 is provided. Eave 18-2 is defined as the portion of roof 18 which extends past the horizontal envelope of building 10 (i.e. past exterior walls 16). As an example, eave 18-2 may be designed and/or appropriately coated to serve an aesthetic function, to prevent rain from contacting the surface of exterior walls 16, or prevent the ingress of water at the junction of walls 16 and roof 18, amongst other possible uses.

[0069] In the illustrated examples, both a parapet 16-2 and an eave 18-2 are provided in building 10. Other example configurations are possible, such as where the entire upper surface of exterior walls 16 forms a parapet 16-2, or alternatively where the entire outer perimeter of roof 18 forms a soffit 18-2. In other embodiments, roof 18 has a perimeter substantially conforming to an outer perimeter of walls 16 such that their respective outer surfaces are flush with one another.

[0070] Although not illustrated, single-storey buildings described herein may comprise any number of desired interior walls, that is, walls disposed within the enclosed space defined by floors 14, walls 16 and roof 18. Different ones of the interior walls may have different properties depending on their desired application. For example, interior walls may include, but are not limited to, the following types of walls:

• fire walls for enclosing a space that requires heightened fire protection;

• demising walls for separating adjacent rooms or units which require a degree of acoustic insulation; and

• corridor walls for defining corridors, hallways, and the like.

It is generally not necessary that these interior walls be made load bearing as structural walls such as foundation walls 12 and exterior walls 16 can typically adequately accomplish this task. However, in some embodiments of the invention, interior walls are constructed to be load bearing.

[0071] In some embodiments, interior walls are used to separate different rooms of a private dwelling. In another example embodiment, interior walls define at least a portion of a walk-in commercial freezer adjacent a commercial kitchen. In such an example, the interior walls are preferably made from prefabricated panels having a high R-value for thermal resistance and comprise appropriate cladding or other sealing for sealing the freezer from the external kitchen environment.

[0072] Figure 8 is a perspective view of an assembled single-storey building 200 comprising foundation walls 12, floor 14, exterior walls 16 and roof 18. Building 200 is similar to building 10 of the Figure 1 embodiment with the difference that building 200 comprises an irregular non-rectangular shape as opposed to building 10 which comprises a uniform rectangular cross-section. As illustrated in Figure 9, building 200 may comprise a plurality of exterior panels 26F which connect at both an interior facing surface and an exterior facing surface to other ones of exterior panels 26 in order to facilitate different building shapes. By applying a similar principle to roof panels 28 in conjunction with exterior panels 26 having differing heights, single-storey buildings with a varying vertical profile may be achieved.

[0073] Any interior facing or exterior facing surfaces of panels 22, 24, 26 and 28 may be coated with a cladding, siding or finish to protect the building materials and/or to achieve a desired aesthetic effect. For example, any of panels 22, 24, 26 and 28 may be coated with a waterproof membrane or have mechanically attached cladding to interior and/or exterior faces with materials such as formed metal panels, glass, or granite sheet.

[0074] All of the required prefabricated panels described herein suitable for constructing a single-storey building may be manufactured and pre-finished in a plant. The panels may be transported to a jobsite efficiently in dense stacks and then connected by any appropriate means for creating the desired single-storey building. Systems and methods described herein provide for the cost effective and environmentally friendly construction of a structurally sound, weather-resistant and insulated building envelope which may have fully or partially finished interior and exterior walls.

[0075] Using the systems and methods described herein, single-storey buildings which are highly energy efficient and thereby reduce energy consumption can be produced. The building envelope of single-storey buildings described herein can be highly insulative due to the use of composite insulative building materials. For example, the requisite R-value for achieving the ‘passive house’ energy efficiency standard may be provided in single-storey buildings described herein. According to an example embodiment, a single-storey building is provided using exterior wall panels 26 having an R-50 insulation value and using roof panels 28 having an R-100 insulation value, all of the panels lacking thermal bridges.

[0076] The scope of the present invention includes a variety of possible supplementary designs to single-storey buildings and/or other aspects of single-storey buildings. Where suitable, these variations may be applied to any of the single-storey building embodiments described herein and include, without limitation, the following: • the use of prefabricated panels for creating one of more of the foundation walls, the floor, the exterior walls, and the roof in conjunction with the use of traditional concrete construction techniques for one or more of the foundation walls, the floor, the exterior walls, and the roof. For example, the foundation walls may be cast in place concrete walls supporting a cast in place concrete slab serving as the floor of the building. Prefabricated panels may be used for the construction of exterior walls and the roof, the walls and roof supported by the concrete foundation walls and/or the slab;

• piping and other tubes running through insulative cores of prefabricated panels described here may be encased in plastic or metal conduit bodies;

• cross bracing between structural elements (e.g. HSS steel frames) embedded around the perimeter of an insulative core of foundation panels 22 may be provided in a manner similar to cross brace 46 described in relation to exterior panels 26 to advantageously impart shear resilience to foundational panels 22;

• a single prefabricated panel may serve as both a foundation panel 22 and as an exterior wall panel 26. For example, a unitary prefabricated panel may comprise a portion located below grade and comprise a portion located above grade when installed in single-storey buildings of the present invention;

• prefabricated exterior wall panels 26 located above grade when installed in single storey buildings of the present invention may comprise a lower portion serving as a foundation for the building. The lower portion of panels 26 in such embodiments should have sufficient compressive, transverse, and shear load bearing capacity; and

• prefabricated panels of the present invention may comprise a non-uniform composition and cross-section along either a length of the prefabricated panel, a width of the prefabricated panel, or both. In the above example embodiments comprising a single panel having increased structural requirements in a lower portion of the panel, a thickened composite cementitious layer may be provided in the lower portion, optionally with a greater number and/or thickness of metal reinforcing bars disposed therein. In such embodiments, the lower portion of the panel may comprise a greater overall thickness than the upper portion of the panel. In some embodiments, the lower portion of prefabricated panels having greater structural requirements comprises a different coating than the upper portion of the panel.

Interpretation of Terms

[0077] Unless the context clearly requires otherwise, throughout the description and the claims:

• “comprise”, “comprising”, and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”;

• “connected”, “coupled”, or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof;

• “herein”, “above”, “below”, and words of similar import, when used to describe this specification, shall refer to this specification as a whole, and not to any particular portions of this specification;

• “or”, in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list;

• the singular forms “a”, “an”, and “the” also include the meaning of any appropriate plural forms.

[0078] This description employs a number of simplifying directional conventions. Directions are described in relation to a building having an existing vertical building wall and an existing horizontal roof. Directions may be referred to as: “external”, “exterior”, “outward” or the like if they tend away from the building; “internal”, “interior”, “inward” or the like if they tend toward the building; “upward” or the like if they tend toward the top of the building; “downward” or the like if they tend toward the bottom of the building; “vertical” or the like if they tend upwardly, or downwardly, or both upwardly and downwardly; “horizontal”, “sideways” or the like if they tend in a direction orthogonal to the vertical direction. Those skilled in the art will appreciate that these directional conventions are used for the purpose of facilitating the description and should not be interpreted in the literal sense. In particular, the invention may be adapted for buildings which have walls that are not strictly vertically oriented and/or roofing structures that are inclined.

[0079] For example, while processes or blocks are presented in a given order, alternative examples may perform routines having steps, or employ systems having blocks, in a different order, and some processes or blocks may be deleted, moved, added, subdivided, combined, and/or modified to provide alternative or subcombinations. Each of these processes or blocks may be implemented in a variety of different ways. Also, while processes or blocks are at times shown as being performed in series, these processes or blocks may instead be performed in parallel, or may be performed at different times.

[0080] In addition, while elements are at times shown as being performed sequentially, they may instead be performed simultaneously or in different sequences. It is therefore intended that the following claims are interpreted to include all such variations as are within their intended scope.

[0081] Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions, and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be apparent to the skilled addressee, including variations obtained by: replacing features, elements and/or acts with equivalent features, elements and/or acts; mixing and matching of features, elements and/or acts from different embodiments; combining features, elements and/or acts from embodiments as described herein with features, elements and/or acts of other technology; and/or omitting combining features, elements and/or acts from described embodiments.

[0082] Various features are described herein as being present in “some embodiments”.

Such features are not mandatory and may not be present in all embodiments. Embodiments of the invention may include zero, any one or any combination of two or more of such features. This is limited only to the extent that certain ones of such features are incompatible with other ones of such features in the sense that it would be impossible for a person of ordinary skill in the art to construct a practical embodiment that combines such incompatible features. Consequently, the description that “some embodiments” possess feature A and “some embodiments” possess feature B should be interpreted as an express indication that the inventors also contemplate embodiments which combine features A and B (unless the description states otherwise or features A and B are fundamentally incompatible). [0083] It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions, omissions, and sub-combinations as may reasonably be inferred. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole.

Claims

CLAIMS:

1 . A method of constructing a single-storey building utilizing a plurality of prefabricated structural insulated panels, each of the plurality of prefabricated structural insulated panels comprising a first cementitious layer, a second cementitious layer, and an insulative core, wherein the insulative core is disposed between the first and second cementitious layers, the method comprising: i) constructing a building foundation; and ii) constructing the single-storey building on said foundation, the building comprising: an exterior wall supported by at least said building foundation, said exterior wall comprising a first plurality of the prefabricated structural insulated panels, the first plurality of structural panels forming the exterior wall disposed on an outer perimeter of the building; and a roof supported by at least said exterior wall and comprising a second plurality of prefabricated structural insulated panels, the second plurality of structural panels forming said roof of the single-storey building.

2. A method according to claim 1 wherein the building comprises a foundation wall constructed on said foundation comprising a third plurality of said prefabricated structural insulated panels, the third plurality of structural prefabricated insulated panels comprising prefabricated load-bearing structural insulated panels forming the foundation wall disposed on an outer perimeter of the building wherein at least one of the first and second cementitious layers are structurally reinforced and wherein the foundation wall interposes the foundation and the exterior wall.

3. A method according to claim 2 wherein the building comprises a floor supported by at least the foundation wall, the floor comprising a fourth plurality of said structural prefabricated insulated panels.

4. A method according to any one of claim 1 to 3 wherein each of the first plurality of panels has a height to width ratio of at least 2.5 to 1 .

5. A method according to any one of claims 1 to 3 wherein each of the first plurality of panels has a width to height ratio of at least 2.5 to 1 .

6. A method according to any one of claims 1 to 5 wherein one or more of the structural prefabricated insulated panels each comprise a cross brace, the cross brace comprising a plurality of intersecting diagonal supports.

7. A method according to claim 6 wherein each of the one or more structural prefabricated insulated panels comprise a frame disposed about a perimeter of the panel.

8. A method according to claim 7 wherein each of the plurality of intersecting diagonal supports are fixedly connected at different corresponding corners of the frame.

9. A method according to claim 6 wherein each of the plurality of diagonal supports comprises hollow structural section steel.

10. A method according to claim 6 wherein the cross brace is embedded within the insulative core of each of the one or more prefabricated panels.

11. A method according to claim 10 wherein the insulative core of each of the one or more prefabricated panels comprising a cross brace comprises a depression in which the cross brace is seated.

12. A method according to claim 11 wherein the cross brace is bonded to the insulative core of each one of the one or more prefabricated structural panels by curing one of the first and second cementitious layers over top of the cross brace and depression.

13. A method according to claim 6 wherein the one or more prefabricated structural insulated panels comprising a cross brace include each of the first plurality of panels forming the exterior wall.

14. A method according to claim 6 wherein the one or more prefabricated structural insulated panels comprising a cross brace include each of the third plurality of panels forming the foundation wall.

15. A method according to claim 1 wherein the foundation comprises one or more of: a concrete footing; a monolithic concrete slab; and a cast in place concrete wall.

16. A method according to any one of claims 1 to 15 comprising a plurality of interior walls comprising a fifth plurality of the prefabricated structural insulated panels, the interior walls disposed within a space defined by at least the first and second plurality of panels.

17. A method according to any one of claims 1 to 16 wherein one or more of the plurality of prefabricated structural panels comprises a non-uniform cross-section along at least one of a height and a width of the prefabricated panel.

18. A method according to any one of claims 1 to 17 wherein a lower portion of each one of the first plurality of prefabricated panels forming exterior walls comprises a greater cross-sectional area than a corresponding upper portion of each one of the first plurality of prefabricated panels.

19. A method according to any one of claims 1 to 18 wherein each one of the second plurality of prefabricated structural panels forming the roof comprises a non-uniform cross-section along both a height and a width of each one of the second plurality of prefabricated panels.

20. A method according to claim 19 comprising positioning the second plurality of prefabricated structural panels such that the non-uniform cross-section of adjacent ones of the second plurality of prefabricated panels define a drainage channel.

21 . A method according to any one of claims 1 to 20 wherein a cavity is defined along a longitudinal length of the insulative core of one or more of the plurality of prefabricated structural insulated panels.

22. A method according to claim 21 wherein a pipe for delivering radiant heat to the building is disposed within said cavity.

23. A method according to claim 22 wherein the pipe for delivering radiant heat is in communication with one of the first cementitious layer and the second cementitious layer.

24. A system for constructing a single-storey building, the system comprising: a building foundation; and a plurality of prefabricated structural insulated panels, the prefabricated panels comprising: a first cementitious layer, a second cementitious layer; and an insulative core, the insulative core disposed between the first and second cementitious layers; wherein: a plurality of the prefabricated structural panels comprise foundation panels disposed on an outer perimeter of the building and the foundation panels comprise opposing top and bottom edges, wherein the bottom edge of the foundation panels connect to the building foundation and wherein said first and second cementitious layers of the foundation panels are structurally reinforced; a plurality of the prefabricated structural panels comprise wall panels, the wall panels comprising opposing top and bottom edges; a plurality of the wall panels comprise exterior wall panels disposed on an outer perimeter of the single-storey building, each exterior wall panel connecting to two adjacent exterior wall panels; a plurality of prefabricated panels comprise roof panels, each roof panel connecting to at least one of: the top edge of one or more exterior wall panels; and an upper interior surface of one or more exterior wall panels; one or more of the plurality of prefabricated panels comprise floor panels, each floor panel located adjacent the bottom edges of one or more exterior wall panels.