WO2022201165A1

WO2022201165A1 - Volumetric modules

Info

Publication number: WO2022201165A1
Application number: PCT/IL2022/050331
Authority: WO
Inventors: Yaniv VAKNIN; Netanel BUTA; Zeev NAVON
Original assignee: Modulart
Priority date: 2021-03-25
Filing date: 2022-03-24
Publication date: 2022-09-29

Abstract

A corner unit for volumetric modules having at least four horizontal beams at each of a floor and a ceiling, the floor and the ceiling being configured to be connected in corners by at least four posts, the corner unit connecting at least two horizontal beams and at least one post, the corner unit comprising: a. a first beam segment having a hollow structural section and at least one open side to receive at least one post thereinto; b. a flat rectangular plate inside said first beam segment and perpendicular to walls of said first beam segment, the plate being connected directly or indirectly to the internal walls of the first beam segment, and having a hole for receiving a bolt therein; c. at least two beam connectors attached to at least two respective external walls of said first beam segment for receiving at least two horizontal beams of said at least four horizontal beams, each beam connector including: A. a box having at least one open face bordered by a first side and a second side parallel to each other; B. said first side welded to an external wall of the first beam segment; and C. said second side having a face with at least two holes for receiving bolts for attaching said beam connector to a horizontal beam of said at least four horizontal beams.

Description

VOLUMETRIC MODULES

BACKGROUND OF THE INVENTION

BACKGROUND

Volumetric modules are used in modular buildings. A modular building is a prefabricated building that consists of repeated sections, the volumetric modules. The modules are constructed away from the building site, and then are delivered to the intended or job site. In the job site, the volumetric modules are placed using a crane, side-by-side, end-to-end, or stacked, allowing for a variety of configurations and styles, including multi-storey building. After placement, the modules are joined together using inter-module connections, inter-connections, and form the overall building structure.

BRIEF SUMMARY OF THE INVENTION

According to one aspect, a comer unit for volumetric modules is provided. The volumetric modules have at least four horizontal beams at each of a floor and a ceiling, the floor and the ceiling are connected in corners by posts, and the comer unit connecting at least two horizontal beams and at least one post. The comer unit comprises a first beam segment having a hollow structural section and at least one open side to receive at least one post thereinto, a flat rectangular plate inside the first beam segment and perpendicular to walls of the first beam segment, and at least two beam connectors attached to at least two respective external walls of the first beam segment for receiving at least two horizontal beams. The plate is connected directly or indirectly to the internal walls of the first beam segment and has a hole for receiving a bolt therein. Each beam connector includes a box having at least one open face bordered by a first side and a second side parallel to each other. The first side is welded to an external wall of the first beam segment. The second side has a face with at least two holes for receiving bolts for attaching the beam connector to a horizontal beam.

In some embodiments, the at least two respective external walls of the first beam segment receiving the at least two beam connectors are adjacent to each other.

In some embodiments, the first beam segment has a square hollow structural section. In some embodiments, the first side is open and has three edges welded to an external wall of the first beam segment.

In some embodiments, at least one rib is welded to both the second side of the box and an adjacent side of the box.

In some embodiments, the flat rectangular plate is attached to a second beam segment residing, at least in part, inside the first beam segment. The second beam segment is welded to internal walls of the first beam segment.

In some embodiments, the box is made by folding a metal sheet and by welding neighboring edges. Alternatively, the box is made by cutting a segment of a U-shaped beam and welding the second side of the box to a web and to two flanges of the segment.

In some embodiments, the corner unit further comprises a flat section protruding from the second side forming an L- shape plate, and a flat leg perpendicularly protruding from the flat section. The flat leg having a hole for receiving a bolt for attachment of an article. Preferably, the article is an L- shaped internal beam of the floor or the ceiling configured to be attached to the flat leg using the hole thereof.

In some embodiments, a volumetric module has at least one the above comer units.

According to one aspect, a method for installing comer units of volumetric modules is provided. The volumetric modules have at least four horizontal beams at each of a floor and a ceiling, and the floor and the ceiling are connected in comers by posts. The corner unit comprises a first beam segment having a hollow structural section and at least one open side, a flat rectangular plate inside the beam segment in perpendicular to walls of the beam segment, the plate having a hole for receiving a bolt therein, and at least two beam connectors attached to at least two respective external walls of the beam segment for receiving at least two horizontal beams.

Each beam connector includes a box having an open face bordered by a first side and a second side parallel to each other. The first side is welded to an external wall of the beam segment, and the second side has a face with at least two holes.

The method comprises attaching two horizontal beams to a first corner unit using holes in second sides of the beam connectors attached to the first beam segment of the first corner unit, inserting a bolt equipped post inside the first beam segment such that the bolt infiltrates the hole in the flat rectangular plate, and fastening a nut on the bolt. In some embodiments, the method further includes placing a second comer unit on a second end of the post, and engaging the second comer unit with the second end of the post.

In some embodiments, a flat rectangular plate of a third comer unit is attached to a second beam segment residing, at least in part, inside a first beam segment of the third corner unit, and welded to internal walls thereof. The method further includes inserting the second beam segment of the third corner unit into the first beam segment of the second corner unit, and attaching the third comer unit to the second corner unit.

Alternatively, a flat rectangular plate of the second corner unit is attached to a second beam segment residing, at least in part, inside a first beam segment of the second corner unit, and welded to internal walls thereof. The method further includes inserting the second beam segment of the second comer unit into the first beam segment of the third corner unit, and attaching the third comer unit to the second comer unit.

In some embodiments, a flat section perturbs from the second side forming an L- shape plate, and a flat leg perturbs perpendicular to the flat section. The flat leg has a hole, and an internal beam of the ceiling or the floor is configured to be attached to the flat leg using the hole. The method further includes connecting the internal beam of the floor or of the ceiling to the flat leg.

According to one aspect, a rectangular panel unit is provided. The unit has two parallel first sides and two parallel second sides for constructing a wall with one or two rectangular panel units neighboring at respective one or two first sides. The rectangular panel unit comprises two external rectangular boards, spaced for receiving at least one substance in between, two sets of one or more bars disposed between the two external rectangular boards at two edges of the first sides of the panel unit, two U-shaped sheet metals, and a sheet metal coupler.

Each bar has an external toothed side for tight coupling with a toothed side of a bar of a neighboring rectangular panel unit. The two U-shaped sheet metal encompass the two second sides of the panel unit, such as to strongly hold edges of the two rectangular external boards, the at least one substance, and the two bars. The sheet metal coupler couples one of the two U-shaped sheet metals to a U-shaped beam of a skeleton of a volumetric module. The coupler is shaped as a riser-tread-riser combination, whereby the coupler tread is attached to a web of the U-shaped sheet metal, a first riser is attached to a flange of the one of the two U-shaped sheet metals and a second riser is attached to a flange of the U-shaped beam.

In some embodiments, an internal rectangular board is disposed adjacent to one of the two external rectangular boards.

In some embodiments, the rectangular panel unit includes a thermal insulation material in between the two external rectangular boards.

In some embodiments, the toothed bars are made of wood.

In some embodiments, the coupler tread and the web of the U-shaped sheet metal have at least one pair of overlapping holes for receiving a service channel.

In some embodiments, horizontal bars are interlaced with the two sets of one or more bars.

According to one aspect, a method for using a rectangular panel unit is provided. The rectangular panel unit has two parallel first sides and two parallel second sides for constructing a wall with one or two panel units neighboring at one or two first sides of the panel unit. The method comprises a step of attaching two external rectangular boards, spaced for receiving at least one substance in between, with two sets of one or more bars disposed between the two external rectangular boards at two edges of the first sides of the panel unit, each bar of at least one set of bars having an external toothed side for integration with a toothed side of a bar of a neighboring rectangular panel unit.

The method further includes clasping the two second sides of the panel unit using two U-shaped sheet metals, such as to strongly hold edges of the two rectangular external boards, and the two sets of one or more bars.

The method further includes a step of coupling the panel unit to a U-shaped beam of a skeleton of a volumetric module using a sheet metal coupler. The sheet metal coupler resides between a U-shaped sheet metal and the U-shaped beam, and is shaped as a riser-tread-riser combination. The step of coupling includes attaching the coupler tread to a web of the U-shaped sheet metal, attaching a first coupler riser to a flange of a U-shaped sheet metal and attaching a second coupler riser to a flange of the U-shaped beam.

In some embodiments, the method further includes integrating a set of one or more toothed bars of the rectangular panel unit with a corresponding set of one or more toothed bars of a neighboring panel unit. In some embodiments, the method further includes attaching an internal rectangular board between the two external rectangular boards.

In some embodiments, the method further includes inserting a service channel between the boards in a substantially parallel direction to the first sides.

In some embodiments, the method further includes inserting a thermal insulation material between the two external rectangular boards.

In some embodiments, the method further includes interlacing horizontal metallic bars with the two sets of one or more toothed bars.

In some embodiments, the method further includes inserting a service channel through matching holes in the coupler tread and in the web of the U-shaped sheet metal.

A beam fastener for using in fastening parallel beams is disclosed. The beams have flanges and webs. The beam webs have holes for receiving web bolts. The beam fastener includes a fastener web plate and a fastener overhang plate. The fastener web plate has at least one hole sized essentially identically to the beam web holes. The fastener overhang plate extends from a distance of at least ½ * (flange width- web thickness) of the one of the beams away from the fastener web plate. The fastener overhang plate has at least one hole for receiving flange bolts .

The first beam fastener can be used with additional beam fastener/s, flange bolts and nuts to fasten together flanges of adjacent beams. It can also be used with additional beam fastener/s, bolts and nuts to fasten together two beam webs .

In some embodiments, sidewalls connect the fastener web plate with the fastener overhang plate. A sidewall has two or three adjacent edges normal to each other for engagement with a beam web and with the beam flanges .

The term “essentially identically” in “The fastener web plate has at least one hole sized essentially identically to the beam web holes” means that the web plate hole and an aligned beam web hole both have a size such that a bolt can be easily slid through both, yet the bolt is snug in both holes. Typically, the web-plate holes and the web holes each have diameters that vary by no more than 1mm.

According to another aspect a modified beam is provided, comprising: a beam having flanges and at least one web, the beam webs having holes for receiving web bolts; a first beam fastener affixed to the beam and comprising: a. a fastener web plate having at least one hole aligned with, and sized essentially identically to, a beam web hole; and b. at least one fastener overhang plate, extending away from a flange, and having at least one hole for receiving flange bolts , whereby a first modified beam can be used: with a second modified beam and at least one flange bolt and a nut to fasten together flanges of adjacent first and second modified beams, and with a third modified beam and at least one web bolt and at least one nut to fasten together webs of first and third modified beams .

In some embodiments the first beam fastener is sized to snugly fit into a span between a beam’s flanges. A modified beam is created by affixing a first beam fastener to the beam

In some particular embodiments the first beam fastener is welded to flanges and a web of a beam .

In some embodiments, the beams are U-shaped beams, C-shaped beams, Id- shaped beams, I- shaped beams, S -beams, and a mixture thereof.

In some embodiments, nuts are stitched to some of the fastener holes, thus saving a worker at a job site from the need to access the hole with a nut while screwing a bolt therein .

In some embodiments, a sheet metal is folded into the beam fastener and only two edges need to be stitched after folding. Preferably, the thickness of the sheet metal is in a range of 5 to 10 mm .

In some embodiments, a building element includes two beam fasteners and two parallel beams adjacent in respective beam flanges. The beam flanges are fastened to each other by the overhang plates and the sidewalls of the beam fasteners .

In some embodiments, a building element includes two beam fasteners and two parallel beams adjacent in respective beam webs. The beam webs are fastened to each other by bolts, penetrating fastener webs and beam webs, and by nuts therein. BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to system organization and method of operation, together with features and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanied drawings in which:

Fig. 1A is a perspective view of a construction consisting of four volumetric modules in two stories.

Fig. IB is a perspective view of a horizontal U-shaped beam used in a volumetric module as part of its skeleton.

Fig. 1C depicts an enlargement of an end of the U-shaped beam showing a beam fastener therewithin.

Fig. 2 illustrates a pair of beam fasteners fastening two flanges of respective two U- shaped beams.

Fig. 3A is a perspective view of a beam fastener.

Fig. 3B is a top view of the beam fastener of Fig. 3A.

Fig. 3C is a rear view of the beam fastener of Fig. 3A.

Fig. 3D depicts a sheet metal shaped for being folded as the beam fastener of Fig. 3A. Fig. 3E is a side view of the beam fastener of Fig. 3A.

Fig. 4 A is a perspective view of a beam fastener with stitched nuts.

Fig. 4B is a top view of the beam fastener of Fig. 4A.

Fig. 4C is a rear view of the beam fastener of Fig. 4A.

Fig. 5A is a side view of the construction of Fig. 1 A showing a first pair of volumetric modules in two stories. A second pair of volumetric modules in two story’s is partially hidden behind the first pair of volumetric modules.

Fig. 5B is a cross-section view along the plane designated in Fig. 5A, showing the two pairs of volumetric modules meeting along a central line vertical to the page.

Fig. 5C is an enlargement of the central part of the cross-section view of Fig. 5B.

Fig. 5D is a further enlargement of the central part of the cross-section view of Fig. 5C showing only four beam fasteners within respective four coupled U-shaped beams.

Fig. 6 is a flowchart of a method for fastening U-shaped beams. Fig. 7 is an exploded perspective view of a section of a wall of a volumetric module which includes two panel units between a floor beam and a ceiling beam and between two posts.

Fig. 8A is a side cross-section view of a panel unit of Fig. 7.

Fig. 8B is an enlargement of the upper part of Fig. 8A.

Fig. 8C shows a service channel inserted within a panel unit through holes in the U- shaped sheet metal and the riser-tread-riser coupler.

Fig. 8D is a horizontal cross-section view of two panel units attached together by toothed bars.

Fig. 8E is a perspective view of a panel unit having toothed bars in vertical sides of the panel unit.

Fig. 8F is an enlargement of the left upper corner of the panel unit of Fig. 8E.

Fig. 8G is an enlargement of the right upper corner of the panel unit of Fig. 8E.

Fig. 9A schematically illustrates a panel unit with a reinforced internal structure.

Figs. 9B, 9C and 9D are respective enlargements of details B. C and D of Fig. 9A.

Fig. 10 is a flowchart of a method for composing a panel unit and integrating it within a volumetric module.

Fig. 11 A is an exploded view of a skeleton of a volumetric module.

Fig. 1 IB is an exploded view of a floor skeleton of the volumetric module of Fig. 11 A.

Fig. 12A is a perspective view of a floor comer unit for connecting two horizontal perpendicular U-shaped beams and a vertical post.

Fig. 12B is a top view of the floor corner unit of Fig. 11 A.

Fig. 12C is a side cross-section view of the floor comer unit of Fig. 11 A.

Fig. 12D presents a beam connector before integration within the floor corner unit of Fig. 11 A.

Fig. 12E depicts a sheet metal for production of the beam connector of Fig. 1 ID.

Fig. 13 illustrates a floor corner unit having beam connectors made of segments of a U- shaped beam, according to an embodiment.

Fig. 14A illustrates a floor comer unit having two flat legs for connection to internal beams, according to an embodiment.

Fig. 14B depicts a top view of the floor corner unit of 14A.

Fig. 14C illustrates connection of the floor corner unit to an external beam and an internal beam of the floor. Fig. 14D is an enlargement of the floor corner unit and the connected external and internal beams.

Fig. 15A is a perspective view of a ceiling corner unit for connecting two horizontal perpendicular U-shaped beams and a vertical post.

Fig. 15B is a top view of the ceiling comer unit of Fig. 15A.

Fig. 15C is a side cross-section view of the ceiling comer unit of Fig. 15A.

Fig. 16A depicts a post having a nut-equipped top end for coupling the post to a ceiling corner unit and a bolt-equipped bottom end for coupling the post to a floor corner unit.

Fig. 16B is an enlargement of the nut-equipped top end of the post of Fig. 13A.

Fig. 16C is an enlargement of the bolt-equipped bottom end of the post of Fig. 13A. Fig. 17A shows a first level volumetric module over a ground level module.

Fig. 17B is an enlargement of Fig. 14A which shows a post within a floor corner unit over a post within a ceiling corner unit.

Fig. 17C is an exploded view of Fig. 14B.

Fig. 18 is a flowchart of a method for using comer units.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described in terms of specific example embodiments. It is to be understood that the invention is not limited to the example embodiments disclosed. It should also be understood that not every feature of the methods and systems is necessary to implement the invention as claimed in any particular claim of the appended claims. Various elements and features of devices are described to fully enable the invention. It should also be understood that throughout this disclosure, where a method is shown or described, the steps of the method may be performed in any order or simultaneously, unless it is clear from the context that one step depends on another being performed first.

Before explaining several embodiments of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The systems, methods, and examples provided herein are illustrative only and not intended to be limiting.

In the description and claims of the present application, each of the verbs "comprise", "include" and "have", and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb.

A modular building is a prefabricated construction that consists of volumetric modules. The modules are constructed away from the building site, and then are delivered to the job site. In the job site, the volumetric modules are placed using a crane.

The walls of volumetric modules are installed before or after the volumetric modules arrive the building site.

Fig. 1A shows a construction 2 consisting of four volumetric modules in two stories. In the ground level, module 4 is positioned side by side with module 6. In the first level (a level directly above ground level), module 8 is positioned on module 4 and is located side by side with module 10, which in turn resides over module 6.

After placement the modules 4, 6, 8 and 10 are joined together in their respective beams using inter-connections, and form the overall building structure 2, as discussed in the next section.

The walls of the volumetric modules may consist of panel units installed side by side between floor and ceiling beams, as further discussed in a following section.

Each of the modules of Fig. 1 A includes four floor beams, four posts four ceiling beams, and eight comer units. Each corner unit connect together two perpendicular beams and a post, as described below.

A beam fastener (Figs. 1-6)

In the example of Fig. 1A, the floor and ceiling beams may be modified U-shaped beams 12, as shown in Fig. IB and in the enlarged view of Fig. 1C. A U-beam includes a web 14 and two flanges 16. The beam web 14 is vertical to the ground and faces the outside of the volumetric module. The beam flanges 16 are posed essentially horizontally while their edges 17 are directed inward the module 4, 6, 8 or 10. A beam fastener 18 is disposed within the U-beam and may be welded to it as further explained below to form a modified U-beam 12. The beam fastener 18 allows fastening of modified U-beam 12 to another modified U-beam 12 of an adjacent module as shown in the example of Fig. 2.

End plates 20 are stitched to edges 22 of modified U-beam 12 to enable connection with comer units as further described in a following section. Also, several plates 24 are distributed along the internal side of web 14 for connection to corresponding ceiling beams 26 and to the corresponding floor beams 26', as shown in Fig. 1A.

Fig. 2 illustrates a pair of beam fasteners 18 and 18N fastening two U-shaped beams 12 by their flanges 16. Each of the beam fasteners 18 and 18N include a fastener web plate 30 and a fastener overhang plate 32. The fastener web plate 30 has holes 34 sized essentially identical to matching holes 35 in the beam web 14. Thus, bolts (not shown) may be inserted within the matching holes 34 and 35 of the respective webs 30 and 14 and be tightened by appropriate nuts (not shown) to strongly be attached to adjacent beam webs 14.

The fastener overhang plates 32 extend away from the fastener web plate 30 and are disposed proximal to edges 17 of the flanges 16. Each of the overhang plates 32 of respective beam fastener 18 and 18N has four matching holes 36. Moreover, the overhang plate 32 of beam fastener 18N may have stitched nuts 38 for receiving bolts (not shown) inserted through the holes 36 of the overhang plate 32. The prior stitching of a nut 38 to beam fastener 18N saves a worker at a job site from the need to access the hole 36 with a nut while screwing a bolt therein.

In some embodiments, two or three holes 36 and respective two or three nuts 38 may be used rather than four holes 36 and four nuts 38.

Two sidewalls 40 connect the fastener web plate 30 with the fastener overhang plate 32, as presented in Fig. 3A. A sidewall 40 has three adjacent edges 42, 44 and 46. Edges 42 and 46 are parallel to each other, and both are normal to edge 44, as shown in Fig. 3A. In some embodiments the beam fasteners 18 are sized to snugly fit within the span between the flanges 16: Edges 44 are welded to the beam web 14, while edges 42 and 46 are welded to the beam flanges 16. Thus, sidewalls 40 enhance the integrity and strength of the beam fastener 18 or 18N, and the strength of the inter-connection of the modified U-shaped beams 12. The beam flanges 16 are held together by the overhang plates 32 and edges 42 of sidewalls 40 as shown in the top view of Fig. 3B. The beam flanges 16 are further held together by their connection with the respective beam webs 14 that are each fastened to a beam fastener 18N/18 that in turn are coupled together by nuts 38 and the bolts (not shown) penetrating holes 36.

The beam fasteners 18 and 18N are cut-out boxes of massive construction. A beam fastener 18 may be produced in two steps from a sheet metal 48, shown in Fig. 3D. The first step is folding the sheet metal 48 along lines 50, 52 and 54 in right angles. The second step is stitching edge 56 of fastener web plate 30, shown in Figs. 3D and 3E, with sidewall edge 44. Typically, the thickness of sheet metal 48 is in a range of 5 to 10 mm, 6 mm for example.

A beam fastener 18N, which has stitched nuts 38, is shown in the perspective view of Fig. 4 A, in the top view of Fig. 4B, and in the rear view of Fig. 4C. As mentioned above, the prior stitching of a nut 38 to the beam fastener 18N saves a worker at a job site from the need to access the hole 36 with a nut while screwing a bolt therein.

Reference is given now to coupling of U-shaped beams 12 residing side by side with their respective beam webs 14 close to each other A narrow space may be left between the webs 14 for a sealing layer (not shown). Fig. 5A is a side view of the construction of Fig. 1A showing volumetric module 10 resting on volumetric module 6. Volumetric modules 8 and 4 in two stories are partially hidden behind modules 10 and 6, respectively.

Fig. 5B is a cross-section view along a designated plane 58 of Fig. 5A, showing a meeting zone 60 of volumetric modules 10, 6, 4 and 8. Fig. 5C is an enlargement of the meeting zone 60 of the cross-section view of Fig. 5B . The meeting zone 60 is further enlarged in Fig. 5D which shows beam fasteners 18-UR, 18-LR, 18-LL and 18-UL fastening respective modified U-shaped beams 12-UR, 12-LR, 12-LL and 12-UL.

The beam webs 14 of U-shaped beams 12-UL and 12-UR, for example, are held together between the fastener web plates 30 of the beam fasteners 18-UL and 18-UR using two bolts (not shown) inserted through holes 34 of the fasteners 18-UL and 18- UR and holes 35 of the U-shaped beams 12-UL and 12-UR and by respective two nuts (not shown). Holes 34 and 35 are shown in Fig. 2, Fig. 3C and Fig. 4C.

The beam flanges 16 of the U-shaped beams 12-UR and 12-LR, for example, are held together between the fastener overhang plates 32 of beam fasteners 18-UR and 18- LR as detailed above. A thin sealing sheet 62 may be disposed between the flanges 16 of beams 12-UL and 12-UR and the flanges 16 of beams 12-LL and 12-LR for sealing the interior of the respective volumetric modules 8, 10, 4 and 6.

A method for 100 fastening U-shaped beams is outlined in a flowchart of Fig. 6. The method includes a step 105 of inserting beam fasteners 18 and 18N inside U-shaped beams, and a step 107 of welding the beam fasteners 18 and 18N to the U-shaped beams to make modified U-shaped beams 12. The method further includes a step 110 of inserting bolts in beam web holes 35 and a step 115 of screwing nuts around the bolts. In a preferred embodiment, nuts (not shown) are already stitched to each modified U- shaped beam 12 and the bolts are screwed into them.

The method 100 may also include a step 120 of inserting bolts into fastener holes 36, and a step 125 of screwing the bolts into nuts 38 stitched to a fastener 18N.

The dimensions of the fasteners and the positions of the holes must be carefully controlled to ensure alignment of the holes so that securing the modified beams to each other and to other components of the building is easily performed at the building site.

In some embodiments a beam fastener is first affixed to a u-beam and then a hole is made that goes throughout the beam fastener and the u-beam. Preferably the hole is made at the factory, i.e., not at the building site.

By connecting four u-beams together as described above, the strength of the junctions between the modular volumes is much greater than four times the strength of a single u-beam, in all directions perpendicular to the u-beams’ lengths.

A panel unit (Figs. 7-8)

In some embodiments, the walls of the volumetric modules may consist of panel units installed side by side between floor and ceiling beams. A wall of a volumetric module, module 6 for example, includes a series of rectangular panel units 200, as shown in Fig. 5A. A rectangular panel unit 200 has two parallel vertical sides 204 and two parallel horizontal sides 206, as depicted in Fig. 7. Fig. 7 is an exploded view of a section of a wall of a volumetric module 6 which includes two panel units 200 between a floor beam 12 and a ceiling beam 12 and between two posts 202.

A panel unit 200 may have an adjacent panel unit 200 disposed at each of its two respective vertical sides 204 or one adjacent panel unit 200 at a first vertical side 204 and a post 202 at a second vertical side 204-P. As illustrated in the side cross-section views of Fig. 8A, and the enlarged view of 8B, the panel unit 200 includes two external rectangular boards 208, spaced for receiving additional substances in between. In the example of Figs. 8A and 8B, an additional rectangular board 210 is attached to the board 208 in the inward side. Also, an insulating layer 212 is disposed between the rectangular outward boards 208 and 210.

The insulating layer 212 may be a thermal insulating layer made of rock wall, for example. It may also or alternatively be a layer optimized for acoustic insulation.

The boards 208 and 210 may be plasterboards or wooden boards. The width of the boards 208 and 210 may be chosen to fit standard production measures, a choice that saves excess cutting at the longer sides.

We are referring now to Figures. 8D-8G. Fig. 8D presents a horizontal cross- section view of two panel units 200 attached to each other by two male toothed bars 214 interlaced with two female toothed bars 216. The bars 214 and 216 may be wooden bars.

Alternatively, a single wooden bar may be used in either side. Also, there may be a single tooth in a bar.

The wooden bars 214 and 216 may be made from fire-retardant treated wood. In addition, the design of the volumetric module refrains from continuity of wooden parts, bars 214 and 216 for example, and they are kept isolated from each other. In the case that a fire breaks out in the bars 214 and 216 connecting two panels 200, the fire may fail to spread to other inter-panel connections.

The toothed bars 214 and 216 are disposed along the vertical sides 204 of the panel unit 200, up to the horizontal sides 206, as shown in the perspective view of Fig. 8E. The two corners are enlarged in Figs. 8F and 8G which show the male toothed bars 214 and the female toothed bars 216, respectively, in detail. The male toothed bars 214 protrude beyond the space between the boards 208 or 210.

Further referring to Fig. 8B, U-shaped sheet metal 217 encompasses the upper horizontal side 206 of the panel unit 200 and attaches together edges of the two rectangular external boards 208 and ends of the toothed bars 214 and 216. A web 218 of U-shaped sheet metal 217 covers side 206 of the unit panel 200, while the flanges 219 of sheet metal 217 cover the upper parts of boards 208. Similarly, additional U- shaped sheet metal 217 (not shown) encompasses the lower horizontal side 206 of the panel unit 200. A sheet metal coupler 220 couples a U-shaped sheet metal 217 to a flange 16 of a U-shaped beam 12. The coupler 220 is shaped as a riser-tread-riser combination. A coupler tread 222 is attached to a web 218 of the U-shaped sheet metal 217. By a way of example, tread 222 is attached to the web 218 by screws passing through the tread and screwed into the web.

A first riser 224 is attached to a flange 219 of the U-shaped sheet metal 217, and a second riser 224* is attached to a flange 16 of the U-shaped beam 12. By a way of example, both attachments are by screws passing through the risers 224 and 224* and screwed into the flanges 219 and 16, respectively. The edge of the second riser 224* is directed away from the tread 222, in a direction reversed to the direction that the edge of riser 224 is directed away from the tread 222.

The coupler 220 enables installation by a worker residing outside the volumetric modules. First, the worker attaches the riser 224* and the tread 222 of the coupler to a web 14 and flange 16 of the U-shaped beam 12, respectively. Then, the worker positions the panel 200 in place. Finally, from the inside of the module, a worker attaches the tread 222 and the riser 224 of the coupler 220 to the web 218 and to the flange 219 of the U-shaped sheet metal 217, respectively.

The coupler 220 may be made by folding a sheet metal. The thickness of the sheet metal is chosen in accordance with load calculations performed for the coupling function of coupler 220. Thus, it is especially designed and constructed to withstand the desired load while avoiding too large thickness with the accompanying cost and the additional load on the whole structure.

At certain locations inside the panel unit 200, a service channel 230 has a route which has to penetrate at least one each of the sheet metals 220 and 217. As shown in the exemplary embodiment of Fig. 8C, the coupler tread 222 and the web 218 have respective overlapping holes 232 and 234 for that penetration.

Further referring to Fig. 8D, a series of elongated sheet metal supports 240 are attached to the outward external board 208a. A decorative wall 242 is connected to the supports 240. An elongated support 240 may be designed to be of sufficient size to accommodate a service channel 244. In addition, the supports 240 may be constructive elements that are connected with the upper and lower U-shaped modified beams 12. A support 240 may have a first leg at a certain panel 200 and a second leg on an adjacent panel 200, and thus reinforce the inter-panel connection. A reinforced panel unit (Fig. 9A-D)

In some embodiments, the walls of the volumetric modules may comprise at least one reinforced panel unit 200’ installed between floor and ceiling beams. A wall of a volumetric module, module 6 for example, may include a series of rectangular panel units 200’, as shown in Fig. 9A. Fig. 9A is an exploded view of a section of a wall of a volumetric module 6 which includes two male toothed bars 214’, as depicted in detail b and Fig. 9B, interlaced with two female toothed bars 216’, shown in detail c and Fig. 9C.

In addition, the unit 200’ further comprises at least one horizonal metallic bar 250’ that may be interlaced with the male and female toothed bars 214’, 216’, as presented in Detail D and Fig. 9D.

The panel unit 200’ may further comprise one or more internal plaster boards 210’, at least one external plaster board 208’ and at least one insulating layer 212’ therebetween. External to the external plaster board 208’, a membrane 260’ may be disposed for insulation from moisture, for example.

The male and female toothed bars 214’, 216’ and the boards may be held between an upper coupling clasp 220’ and a lower coupling clasp 220”. One or more of the clasps 220’, 220” may allow piping or a service channel 230’ to pass therethrough and to go through one or more of the boards held therebetween.

A method for constructing and integrating a panel unit (Figs. 7-9)

Fig. 9 is a flowchart of a method 300 for constructing a panel unit 200 and integrating it within a volumetric module 10. The method 300 includes a step 305 of attaching two external rectangular boards 208, spaced for receiving at least one substance in between, with bars 214 and 216 disposed between the two external rectangular boards 208 at two edges of the vertical sides of the panel unit 200.

The method 300 further includes a step 310 of attaching an internal rectangular board 210 between the two external rectangular boards 208, and a step 315 of inserting a service channel 230 between the boards 208 in a direction substantially parallel to that of the vertical sides 204.

The method 300 further includes a step 320 of inserting at least one insulating layer 212 between the two external rectangular boards 208. The method 300 further includes a step 325 of clasping the two horizontal sides 206 of the panel unit 200 using two U-shaped sheet metals 217, such as to strongly hold together edges of the two rectangular external boards 208 and the bars 214 and 216.

The method 300 further includes a step 330 of coupling the panel unit 200 to a U- shaped beam 12 using a sheet metal coupler 220, shaped as a riser-tread-riser combination, between one of the U-shaped sheet metals 217 and the web 14 of the U- shaped beam 12. The method 300 further includes a step 335 of inserting a service channel 230 through matching holes 232 and 234 in the coupler tread 222 and in the web 218 of the sheet metals 220 and 217, respectively.

The method 300 further includes a step 340 of integrating toothed bars 214 and 216 of the panel unit 200 with corresponding toothed bars 216 and 214 of an adjacent panel unit 200.

The method 300 further includes a step 312 of interlacing horizontal metallic bars 250' with the toothed bars 214' and 216'.

Corner units (Figs. 11-181

A skeleton of a volumetric module includes a floor 400 and a ceiling 402 connected by four steel posts 202, as shown in the exploded views of Figs. 11A and 1 IB. Each of the floor 400 and the ceiling 402 includes four steel beams, U-shaped beams 12 and 12' for example, connected to each other and to posts 202 by floor corner units 404 and by ceiling comer units 506, respectively. The posts 202 have a hollow structural section, preferably a hollow square section.

A floor corner unit 404 is illustrated in the perspective view of Fig. 12A, in the top view of Fig. 12B, and in the side cross-section view of Fig. 12C. The floor comer unit 404 includes two beam segments 410 and 412 and two beam connectors 418 and

420.

The beam segment 410 has a hollow square section 414 and receives a part of the beam segment 412 which has a smaller hollow square section 416. The beam segment 412 is welded to the beam segment 410. The hollow square section 416 may be also the section of posts 202. A flat rectangular e.g., square plate 422 is stitched to the beam segment 412 and has a hole 424 for receiving a bolt welded to a post 202 as further detailed below.

In some embodiments the comer unit’s first side is open and has three edges welded to an external wall of the first beam segment. Each beam connector, 418 or 420, is shaped like a box having only four faces while two adjacent faces are absent, as shown in Fig. 12D. The beam connector 418 may be produced from a sheet metal 421 of Fig. 12E by folding plates 428 and 428B along lines 426A, and by folding plate 430 along line 426B. The folding action is followed by welding lines 428E to adjacent lines 430E. The flange 428B has a hole 444B to which a nut 444 may be stitched to, as shown in Fig. 12A.

The other edges of the flanges 428 and 428B and the other edge of the web 426 are welded to a side 432 of the beam segment 410. The sides 432 which are welded to the beam connectors 418 and 420 are perpendicular to each other, such that two perpendicular U-shaped beams 12 may be attached thereof.

For the attachment to a U-shaped beam 12, the beam receiving plate 430 has three holes 434, while a plate 20 stitched to the end of the U-shaped beam 12, shown in Fig. IB, has three compatible holes 436 of essentially the same size as holes 434. Thus, bolts (not shown) may be inserted from either side and screwed by appropriate nuts on the other side to strongly attach the beam 12 to the corner unit 404. An open side of beam connector 418 or 420 enables access for bolts or nuts, as desired.

In some embodiments, there are only two holes 434 and only two holes 436.

To further strengthen the structure of the beam connector 418 or 420, two adjacent perpendicular sides 438 and 440 of two pentagonal ribs 442 may be welded to the connector web 426 and to the beam receiving plate 430, respectively.

In some embodiments, no ribs are used.

The lower flange 428 may have a hole (not shown) and a welded nut 444 stitched to the hole margin to enable a connection of an article to a bottom flange 428 of the beam connector 418.

Fig. 13 illustrates an alternative floor corner unit 404' in accordance with a preferred embodiment of the invention. Unit 404' has beam connectors 418' and 420', made of segments of a U-shaped beam having a web 426' and flanges 428'. A rectangular beam receiving plate 430 is stitched to edges 428E' of the flanges 428', and to an edge 426E' of the web 426'.

Fig. 14A illustrates another alternative floor corner unit 404" in accordance with a preferred embodiment. Fig. 14B depicts a top view of the unit. Unit 404" has two flat legs 450 for connection to internal beams 26. The flat legs 450 are stitched to beam receiving plates 430L and 430R, which are L-shaped rather than being rectangular. The legs 450 enable connection of internal beams 26' of the floor to the comer unit 404", and thus provide additional strength to the building 2.

Each leg 450 has a hole 455 for receiving a bolt (not shown) which connects the leg 450 to an internal beam 26' as shown in Fig. 4C and in the enlarged view of Fig. 4D.

Alternatively, rather than stitching a flat leg 450 to a beam receiving plate 450L or 450R, a flat leg 450 and a beam receiving plate 430L or 430R may be made from a single metal sheet by folding the end of one of the two perpendicular parts of a larger F- shaped plate.

Figs. 14C and Fig.l4D schematically illustrate the connection of the floor unit 404" to U-shaped beam 12' and to an internal floor beam 26'. The beam 12' is connected to the beam receiving plate 430L of the beam connector 420". The internal beam 26' has an F-shaped cross-section and has an hole 457 close to its end. A bolt (not shown) is inserted into hole 455 (shown in the right leg 450) and in the hole 457, and a nut (not shown) is screwed over the bolt to connect the left leg 450 to the beam 26'.

In some embodiments, a bolt (not shown) is welded to the internal beam 26' for coupling to the leg 450.

We are referring now to a ceiling corner unit 506, shown in the perspective view of Fig. 15A, in the top view of Fig. 15B and in the side cross-section view of Fig. 15C. Ceiling corner unit 506 includes a beam segment 552 and two beam connectors 518 and 520. The beam connectors 518 and 520 are connected to the beam segment 552 in its upper part.

The beam segment 552 has a hollow square section 553. A square plate 550 is stitched to the beam segment 552 and has a hole 554 for receiving a bolt screwed around a nut stitched to the end of post 202. Beam connectors 518 and 520 are similar in shape and construction to beam connector 418 and 420, respectively. To facilitate connection of the ceiling corner unit 506 to an upper story, a nut 556 is stitched to an upper flange 560 of the beam connector 518.

A post 202, as shown in Fig. 16A, has a nut-equipped top end 572, as depicted in Fig. 16B, and a bolt-equipped bottom end 574, as illustrated in Fig. 16C. A bolt 460 traverses a hole in a square plate 464 and is welded to the plate 464, which in turn is stitched to the bottom end 574 of post 202. The bottom end 574 of post 202 penetrates the beam segment 410, and approaches the plate 422, such that the bolt 460 infiltrates the hole 424. Then, a worker screws a nut (not shown) over the bolt 460. A square plate 466 is stitched to the top end 572 of post 202, and it has a hole 468 in its center. A nut 470 is welded to the bottom side of plate 466. The top end 572 of post 202 penetrates beam segment 552 of ceiling corner unit 506 and approaches the plate 550. Then, a worker infiltrates a bolt (not shown) through hole 554 of the ceiling corner unit 506 and via hole 468 and finally screws it into nut 470.

The above description focused on floor and ceiling corner units 404 and 506 in a single volumetric module 10. Floor corner unit 404 and ceiling corner unit 506 meet each other when a volumetric module 8 resides over a volumetric module 4, as depicted in the perspective view of Fig. 17A. As shown in the enlargement of Fig. 17B, and in the exploded view of Fig. 17C, floor corner unit 404 receives the bottom end 574 of the upper post 202 of the first level module 8. A worker may access a bolt 460 at the bottom end 574 of the upper post 202 with a nut (not shown) and screw the nut over the bolt 460.

Ceiling corner unit 506 receives the upper end 572 of the lower post 202, and a worker can infiltrate a bolt 472 into a hole 468 and a nut 470. Then, beam segment 412 of comer unit 404 penetrates the beam segment 552 of corner unit 506, and thus couples the two corner units 404 and 506. Furthermore, the beam connectors 418 and 518 of the two respective comer units 404 and 506 may be tightened together by a bolt screwed into a nut 556 of the beam connector 518.

The combined effect of comer units 404 and 506 interlaced and tightened together, and the effect of the beam fasteners 18 distributed along the beams 12 and tightening them, guarantees that the multi-story construction 2 is strong and stable, and can withstand the challenges it should stand according to building standards.

Flat legs 450, as described above in relation to floor corner unit 404" and depicted in Figs. 14A-D, may be used in ceiling comer unit 506 as well, for connecting ceiling units 506 to internal beams 26.

A method 600 for using floor corner units 404 and ceiling comer units 406 is shown in the flowchart of Fig. 18. The method 600 includes a step 605 of attaching two horizontal beams 12, perpendicular to each other, to a floor corner unit 404, and a step 610 of inserting a bolt-equipped end 574 of a post 202 inside a beam segment 410 of the comer unit 404. The method 600 further includes a step 615 of screwing a nut on a bolt 460 at the end 574 of the post 202. The method 600 further includes a step 620 of placing a ceiling corner unit 506 on the nut-equipped upper end 572 of the post 202, and a step 625 of inserting a bolt 472 via hole 468 and into the nut 470.

The method 600 further includes a step 630 of inserting a beam segment 412 of a floor comer unit 404 connected to beams 12 and post 202 to the beam segment 410 of the ceiling unit 406, and a step 635 of inserting a bolt within a hole of the floor beam connector 418 of the floor corner unit 404 and screwing it to a nut 556 of the beam connector 518 of the ceiling comer unit 506. The prior affixing of the nuts under holes facilitates connecting the units by easily inserting bolt from above during the building up, without need to access underneath to hold the nuts in place during tightening of the bolts.

According to one aspect a method is provided for installing corner units of volumetric modules having at least four horizontal beams at each of a floor and a ceiling, the floor and the ceiling being configured to be connected in corners by at least four posts, a corner unit comprising a first beam segment having a hollow structural section and at least one open side, a flat rectangular plate inside said beam segment in perpendicular to walls of said beam segment, the plate having a hole for receiving a bolt therein, and at least two beam connectors attached to at least two respective external walls of said beam segment for receiving at least two horizontal beams of said at least four horizontal beams, each beam connector including a box having at least one open face bordered by a first side and a second side parallel to each other, the first side being welded to an external wall of the beam segment, and the second side having a face with at least two holes.

The method comprises: a. attaching two horizontal beams to a first comer unit using holes in second sides of the beam connectors attached to the first beam segment of the first comer unit; b. inserting a bolt equipped post inside said first beam segment such that the bolt infiltrates the hole in the flat rectangular plate; c. fastening a nut on the bolt.

In some embodiments the method further includes: d. placing a second comer unit on a second end of the post; e. engaging the second corner unit with the second end of the post. In some embodiments a flat rectangular plate of a third corner unit is attached to a second beam segment residing, at least in part, inside a first beam segment of the third comer unit, and welded to internal walls thereof, and the method further includes: f. inserting the second beam segment of the third corner unit into the first beam segment of the second corner unit; and g. attaching the third corner unit to the second corner unit, as is further explained below.

The order of the steps above fits an installation which starts with a floor comer unit 404, continues with a post 202, and a ceiling corner unit 506, and ends with a second floor corner unit 404.

Another option is up to bottom positioning of a first corner 506, a post, a second unit 404, and a third unit 506 for a second ceiling.

In an alternate reversed order, an installation starts with a ceiling comer unit 506, continues with a post 202 and a floor corner unit 404, and ends with a second ceiling corner unit 506. In more detail, a floor corner unit 404 is placed below a second end of the post 202, and is engaged thereof using a bolt 460 on end of the post 202 and a nut (not shown) screwed thereof. Then, the beam segment 412 of the floor corner unit 404 enters into a beam segment 552 of a ceiling comer unit 506. Finally, the ceiling corner unit 506 is attached to the floor comer unit 404 by their beam connectors 418, a nut 556 thereof and a bolt (not shown), as shown in Figs. 17B and 17C.

The method 600 may further include a step 640 of connecting an internal beam 26' or 26 to a flat leg 450.

To conclude, the beam fasteners 18, the panel units 200 and the comer units 404 and 406 provide a designer with versatile opportunities to design a modular building of several storeys, such that a major part of the work is done in a production facility away from the building site. Moreover, a substantial portion of these elements is prepared using relatively cheap and common profiles and materials.

Claims

1. A comer unit for volumetric modules having at least four horizontal beams at each of a floor and a ceiling, the floor and the ceiling being configured to be connected in corners by at least four posts, the comer unit connecting at least two horizontal beams and at least one post, the corner unit comprising: a. a first beam segment having a hollow structural section and at least one open side to receive at least one post thereinto; b. a flat rectangular plate inside said first beam segment and perpendicular to walls of said first beam segment, the plate being connected directly or indirectly to the internal walls of the first beam segment, and having a hole for receiving a bolt therein; c. at least two beam connectors attached to at least two respective external walls of said first beam segment for receiving at least two horizontal beams of said at least four horizontal beams, each beam connector including:

A. a box having at least one open face bordered by a first side and a second side parallel to each other;

B . said first side welded to an external wall of the first beam segment; and

C. said second side having a face with at least two holes for receiving bolts for attaching said beam connector to a horizontal beam of said at least four horizontal beams.

2. The corner unit of claim 1 wherein said at least two respective external walls of said first beam segment receiving said at least two beam connectors are adjacent to each other.

3. The corner unit of claim 1 wherein said first beam segment has a square hollow structural section.

4. The corner unit of claim 1 wherein said first side is open and having three edges welded to an external wall of the first beam segment.

5. The comer unit of claim 1 wherein at least one rib is welded to both said second side of said box and to an adjacent side of said box .

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6. The comer unit of claim 1 wherein said flat rectangular plate is attached to a second beam segment residing, at least in part, inside said first beam segment, the second beam segment being welded to internal walls of said first beam segment.

7. The corner unit of claim 1 wherein said box is made by folding a metal sheet and by welding neighboring edges.

8. The comer unit of claim 1 wherein said box is made by cutting a segment of a U- shaped beam and welding said second side of said box to a web and to two flanges of the segment.

9. The corner unit of claim 1 further comprising a flat section protmding from said second side forming an L- shape plate, and a flat leg perpendicularly protruding from said flat section, said flat leg having at least one hole, each hole for receiving a bolt for attachment of an article.

10. The comer unit of claim 9 wherein said article is an L-shaped internal beam of the floor or the ceiling, the internal beam being configured to be attached to said flat leg using the hole thereof.

11. A volumetric module having at least one corner unit according to any of the claims

1-10 in at least one respective comer.

12. A method for installing comer units of volumetric modules having at least four horizontal beams at each of a floor and a ceiling, the floor and the ceiling being configured to be connected in corners by at least four posts, a corner unit comprising a first beam segment having a hollow structural section and at least one open side, a flat rectangular plate inside said beam segment in perpendicular to walls of said beam segment, the plate having a hole for receiving a bolt therein, and at least two beam connectors attached to at least two respective external walls of said beam segment for receiving at least two horizontal beams of said at least four horizontal beams, each beam connector including a box having at least one open face bordered by a first side and a second side parallel to each other, the first side being welded to

18 an external wall of the beam segment, and the second side having a face with at least two holes, the method comprising: a. attaching two horizontal beams to a first corner unit using holes in second sides of the beam connectors attached to the first beam segment of the first corner unit; b. inserting a bolt equipped post inside said first beam segment such that the bolt infiltrates the hole in the flat rectangular plate; c. fastening a nut on the bolt.

13. The method of claim 12 further including: d. placing a second comer unit on a second end of the post; e. engaging the second comer unit with the second end of the post.

14. The method of claim 13 wherein a flat rectangular plate of a third corner unit is attached to a second beam segment residing, at least in part, inside a first beam segment of the third corner unit, and welded to internal walls thereof, and the method further includes: f. inserting the second beam segment of the third corner unit into the first beam segment of the second corner unit; and g. attaching the third corner unit to the second corner unit.

15. The method of claim 13 wherein a flat rectangular plate of said second corner unit is attached to a second beam segment residing, at least in part, inside a first beam segment of said second comer unit, and welded to internal walls thereof, and the method further includes: f. inserting the second beam segment of said second comer unit into the first beam segment of the third corner unit; and g. attaching the third corner unit to the second corner unit.

16. The method of claim 12 wherein a flat section protrudes from said second side forming an L-shape plate, a flat leg protruding in perpendicular to said flat section, said flat leg having a hole, and an internal beam of the ceiling or the floor being configured to be attached to said flat leg using said hole, the method further

19 includes a step of connecting said internal beam of the floor or of the ceiling to the flat leg.

17. A rectangular panel unit having two parallel first sides and two parallel second sides for constructing a wall with one or two rectangular panel units neighboring at respective one or two first sides, the rectangular panel unit comprising: a. two external rectangular boards, spaced for receiving at least one substance in between; b. two sets of one or more bars disposed between said two external rectangular boards at two edges of the first sides of the panel unit, each bar of at least one set of bars having an external toothed side for tight coupling with a toothed side of a bar of a neighboring rectangular panel unit; c. two U-shaped sheet metals encompassing the two second sides of the panel unit, such as to strongly hold edges of said two rectangular external boards, said at least one substance, and said two bars; and d. a sheet metal coupler couples one of said two U-shaped sheet metals to a U-shaped beam of a skeleton of a volumetric module, and the coupler is shaped as a riser- tread-riser combination, whereby the coupler tread is attached to a web of said U- shaped sheet metal, a first riser is attached to a flange of said one of said two U- shaped sheet metals and a second riser is attached to a flange of said U-shaped beam.

18. The rectangular panel unit of claim 17 further including an internal rectangular board disposed adjacent to one of said two external rectangular boards.

19. The rectangular panel unit of claim 17 including a thermal insulation material in between said two external rectangular boards.

20. The rectangular panel unit of claim 17 wherein said one or more bars are made of wood.

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21. The rectangular panel unit of claim 17 wherein the coupler tread and the web of said U-shaped sheet metal have at least one pair of overlapping holes for receiving a service channel.

22. The rectangular panel unit of claim 17 wherein at least one horizontal bar is interlaced with said two sets of one or more bars.

23. A method for using a rectangular panel unit having two parallel first sides and two parallel second sides for constructing a wall with one or two panel units neighboring at one or two first sides of the panel unit, the method comprising: a. attaching two external rectangular boards, spaced for receiving at least one substance in between, with two sets of one or more bars disposed between said two external rectangular boards at two edges of the first sides of the panel unit, each bar of at least one set of bars having an external toothed side for integration with a toothed side of a bar of a neighboring rectangular panel unit; b. clasping the two second sides of the panel unit using two U-shaped sheet metals, such as to strongly hold edges of said two rectangular external boards, and said two sets of one or more bars; and c. coupling the panel unit to a U-shaped beam of a skeleton of a volumetric module using a sheet metal coupler between one of said U-shaped sheet metal and said U-shaped beam, said sheet metal coupler is shaped as a riser-tread -riser combination, whereas said step of coupling includes attaching the coupler tread to a web of said U-shaped sheet metal, attaching a first coupler riser to a flange of said one of said two U-shaped sheet metals and attaching a second coupler riser to a flange of said U-shaped beam.

24. The method of claim 23 further including integrating a set of one or more toothed bars of said rectangular panel unit with a corresponding set of one or more toothed bars of a neighboring panel unit.

25. The method of claim 23 further including attaching an internal rectangular board between said two external rectangular boards.

21

26. The method of claim 23 further including a step of inserting a service channel between the boards in a substantially parallel direction to said first sides.

27. The method of claim 23 further including a step of inserting a thermal insulation material between said two external rectangular boards.

28. The method of claim 23 further including a step of interlacing at least one horizontal metallic bar with the two sets of one or more toothed bars.

29. The method of claim 23 further including a step of inserting a service channel through matching holes in the coupler tread and in the web of said U-shaped sheet metal.

30. A first beam fastener for using in fastening parallel beams, each beam having flanges and at least one web and, the beam webs having holes for receiving web bolts, the first beam fastener comprising: a. a fastener web plate having at least one hole sized essentially identically to the beam web holes; and b. at least one fastener overhang plate, extending from distance of at least ½ * (flange width-web thickness) of the one of the beams away from the fastener web plate, said fastener overhang plate having at least one hole for receiving flange bolts , whereby said first beam fastener can be used: with a second beam fastener and at least one flange bolt and a nut to fasten together flanges of adjacent first and second beams, and with a third beam fastener and at least one web bolt and at least one nut to fasten together webs of first and third beams .

31 .A modified beam comprising: a beam having flanges and at least one web, the beam webs having holes for receiving web bolts; a first beam fastener affixed to the beam and comprising: a. a fastener web plate having at least one hole aligned with, and sized essentially identically to, a beam web hole; and

22 b. at least one fastener overhang plate, extending away from a flange, and having at least one hole for receiving flange bolts , whereby a first modified beam can be used: with a second modified beam and at least one flange bolt and a nut to fasten together flanges of adjacent first and second modified beams, and with a third modified beam and at least one web bolt and at least one nut to fasten together webs of first and third modified beams .

32 .The first beam fastener of claim 30 or 31 wherein at least one sidewall connects said fastener web plate with said fastener overhang plate, said at least one sidewall has at least two adjacent edges normal to each other configured for engagement with a beam web and with at least one beam flange .

33 .The first beam fastener of claim 32 wherein said at least one sidewall has three adjacent edges configured for engagement with a beam web and with at two beam flanges.

34 .The first beam fastener of claim 33, wherein the first beam fastener is sized to snugly fit into a span between the beam flanges.

35 .The first beam fastener of claim 34, welded to flanges and a web of a beam .

36. The first beam fastener of claim 30 or 31, wherein the beams are selected from a group consisting of: U-shaped beams, C-shaped beams, H-shaped beams, I-shaped beams, S -beams, and a mixture thereof.

37. A sheet metal foldable into the beam fastener of any of claims 30-36 .

38. The sheet metal of claim 37 having the shape depicted in Figure 3D comprising: a fastener overhang plate, a fastener web plate, and a first sidewall and a second sidewall, wherein: the first sidewall connects the fastener overhang plate to the fastener web plate;

23 the fastener web plate comprises a stitching edge and the second sidewall comprises a rear edge, and the shape allows stitching the rear edge with the stitching edge.

39 .The sheet metal of claim 37 or 38, wherein the thickness of at least one of a fastener web plate and an overhang plate is in a range of 5 to 10 mm .

40 .A beam fastener made from folding the sheet metal of any of claims 37-39 along folding lines depicted in Figure 3D, thereby defining the fastener overhand plate in the sheet metal.

41. A building element comprising two parallel beams adjacent in respective beam flanges and the first and second beam fasteners of claim 32, wherein the beam flanges are fastened to each other by the overhang plates and the sidewalls of the first and second beam fasteners .

42 .A building element comprising two parallel beams adjacent in respective beam webs and the first and second beam fasteners of any of claims 30-36 wherein the beam webs are fastened to each other by bolts penetrating fastener webs and beam webs and nuts therein .

43 .The beam fastener of any one of claims 30-36 or 41, wherein at least one nut is stitched to at least one hole, whereby the stitching saves a worker at a job site from the need to access the hole with a nut while screwing a bolt therein .

44. A construction comprising two or more adjacent volumetric modules, at least two of the adjacent volumetric modules including adjacent parallel beams fastened with at least two beam fasteners of any one of claims 30-36, 39 or 41.

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