EXPANDABLE BUILDING SYSTEMS

Abstract

The present disclosure describes an expandable residential dwelling unit and a set of modular, prefabricated components which can be built offsite, shipped to site, and assembled. The prefabricated components and expandable dwelling unit enable faster, and more cost effective method for adding additional square footage onto a residential dwelling unit. These prefabricated wall components attach to the existing dwelling unit via mechanical connections that maintain a constant thermal and water barrier. Multiple preferred aspects are described herein.

Claims

1. A removable wall assembly for attachment to an exterior wall of a housing unit, wherein the housing unit comprises a first longitudinal wall portion and a second longitudinal wall portion, wherein the first longitudinal wall portion and the second longitudinal wall portion are substantially parallel to one another, wherein the first longitudinal wall portion and the second longitudinal wall portion define an opening therebetween, and wherein the opening defines an opening height and an opening width, and wherein the removable wall assembly is attached the housing unit and defines a wall structure to fill the opening between the first longitudinal wall portion and the second longitudinal wall portion, wherein the removable wall assembly comprises: a patch panel, wherein the patch panel comprises: a first vertical side; a second vertical side, wherein the first vertical side and the second vertical side are substantially parallel to one another; a bottom portion; a top portion, wherein the bottom portion and the top portion are substantial parallel to one another, wherein the first vertical side, the second vertical side, the bottom portion, and the top portion are connected to form the patch panel, and wherein the patch panel has a patch panel height, a patch panel width, and a patch panel thickness; and an attachment mechanism operable between an engaged condition and a disengaged condition; wherein the first vertical side of the patch panel is configured to abut a portion of the first longitudinal wall portion when the patch panel is attached to the housing unit, wherein the bottom potion of the patch panel is configured to abut a portion of a floor system of the housing unit when the patch panel is attached to the housing unit, and wherein the attachment mechanism is configured to releasably attach the patch panel to the housing unit when the attachment mechanism is in the engaged condition.

2. The removable wall assembly of claim 1, wherein the attachment mechanism is configured to releasably attach the bottom portion of the patch panel to the floor system of the housing unit.

3. The removable wall assembly of claim 1, wherein the attachment mechanism is configured to releasably attach the first vertical side of the patch panel to the first longitudinal wall portion of the housing unit.

4. The removable wall assembly of claim 1, wherein the attachment mechanism comprises a cam latch configured to cammingly engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

5. The removable wall assembly of claim 1, wherein the attachment mechanism comprises a key latch, wherein the key latch is operable between an open condition and a locked condition, wherein the key latch is configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit when the key latch is moved from the open condition to the locked condition.

6. The removable wall assembly of claim 1, wherein the attachment mechanism comprises an attachment pin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

7. The removable wall assembly of claim 1, wherein the attachment mechanism comprises an attachment fin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

8. The removable wall assembly of claim 1, wherein the attachment mechanism comprises an attachment bracket configured releasably attach the patch panel to the housing unit.

9. The removable wall assembly of claim 1, wherein the patch panel defines a first patch panel and wherein the removable wall assembly further comprising a second patch panel, wherein the second patch panel comprises: a first vertical side; a second vertical side, wherein the first vertical side and the second vertical side of the second patch panel are substantially parallel to one another; a bottom portion; a top portion, wherein the bottom portion and the top portion of the second patch panel are substantial parallel to one another, wherein the first vertical side, the second vertical side, the bottom portion, and the top portion of the second patch panel are connected to form the second patch panel, and wherein the second patch panel has a second patch panel height, a second patch panel width, and a second patch panel thickness; and a second attachment mechanism operable between an engaged condition and a disengaged condition; wherein the first vertical side of the second patch panel is configured to abut the second vertical portion of the first patch panel when the first and second patch panels are attached to the housing unit, wherein the second vertical side of the second patch panel is configured to abut a portion of the first longitudinal wall portion when the second patch panel is attached to the housing unit wherein the bottom potion of the second patch panel is configured to abut a portion of a floor system of the housing unit when the second patch panel is attached to the housing unit, and wherein the second attachment mechanism is configured to releasable attach the patch panel to the housing unit when the second attachment mechanism is in the engaged condition.

10. The removable wall assembly of claim 9, wherein the top portion of the first patch panel and the top portion of the second patch panel define a removable wall assembly width, and wherein the removable wall assembly width is substantially the same as the opening width.

11. A method for horizontally expanding a housing unit, comprising the removable wall assembly of claim 1, wherein the method comprises: releasing the patch panel from the housing unit by moving the attachment mechanism from the engaged condition to the disengaged condition; removing the patch panel from the housing unit; installing a horizontal addition onto the housing unit; releasably attaching the addition to the housing unit; and reattaching the patch panel to the horizontal addition by moving the attachment mechanism from the disengaged condition to the engaged condition.

12. The method of claim 11, wherein the attachment mechanism comprises a cam latch configured to cammingly engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

13. The method of claim 11, wherein the attachment mechanism comprises a key latch, wherein the key latch is configured to be moved between an open condition and a locked condition, wherein the key latch is configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit when the key latch is moved from the open condition to the locked condition.

14. The method of claim 11, wherein the attachment mechanism comprises an attachment pin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

15. The method of claim 11, wherein the attachment mechanism comprises an attachment fin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

16. The method of claim 11, wherein the attachment mechanism comprises an attachment bracket configured releasably attach the patch panel to the housing unit.

17. A patch panel, wherein the patch panel comprises: a first vertical side; a second vertical side, wherein the first vertical side and the second vertical side are substantially parallel to one another; a bottom portion; a top portion, wherein the bottom portion and the top portion are substantial parallel to one another, wherein the first vertical side, the second vertical side, the bottom portion, and the top portion are connected to form the patch panel, and wherein the patch panel has a patch panel height, a patch panel width, and a patch panel thickness; and an attachment mechanism operable between an engaged condition and a disengaged condition; wherein the first vertical side of the patch panel is configured to abut a portion of a wall portion of a modular housing unit when the patch panel is attached to the modular housing unit, wherein the bottom potion of the patch panel is configured to abut a portion of a floor system of the modular housing unit when the patch panel is attached to the housing unit, and wherein the attachment mechanism is configured to releasable attach the patch panel to the modular housing unit when the attachment mechanism is in the engaged condition.

18. The patch panel of claim 17, wherein the attachment mechanism comprises a cam latch configured to cammingly engage a corresponding attachment portion of a modular housing unit and releasably attach the patch panel to the modular housing unit.

19. The patch panel of claim 17, wherein the attachment mechanism comprises a key latch, wherein the key latch is configured to be moved between an open condition and a locked condition, wherein the key latch is configured to engage a corresponding attachment portion of a modular housing unit and releasably attach the patch panel to the modular housing unit when the key latch is moved from the open condition to the locked condition.

20. The patch panel of claim 17, wherein the attachment mechanism comprises an attachment pin configured to engage a corresponding attachment portion of a modular housing unit and releasably attach the patch panel to the modular housing unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Various features and characteristics of an expandable building system, and more specifically a removable wall system, described in this specification may be more thoroughly understood by reference to the accompanying figures, in which:

[0013] FIGS. 1A-1K illustrate the process of making a horizontal addition to an existing dwelling unit that was originally built to receive an addition. The process includes the steps of removing a removable wall system, adding an additional room onto an original residential dwelling, and reattaching the removable wall system, where:

[0014] FIG. 1A illustrates an axonometric view of the original dwelling unit;

[0015] FIG. 1B illustrates the faade of the original dwelling unit from FIG. 1A in the process of being removed to begin the expansion process

[0016] FIG. 1C illustrates the faade removed, revealing removable patch panels and quick-connect bracket system of the original dwelling unit from FIG. 1A;

[0017] FIG. 1D illustrates the patch panels in the process of being removed from the original dwelling unit from FIG. 1A;

[0018] FIG. 1E illustrates the original dwelling unit of FIG. 1A with a void where the patch panels were previously located;

[0019] FIG. 1F illustrates additional square footage being connected to the original dwelling unit of FIG. 1A through the addition of floor and roof panels;

[0020] FIG. 1G illustrates the patch panels in the process of being re-attached to the extended dwelling unit of FIG. 1A;

[0021] FIG. 1H illustrates the patch panels re-attached to the extended dwelling unit of FIG. 1A;

[0022] FIG. 1I illustrates the faade of the original dwelling unit of FIG. 1A in the process of being re-attached onto the extended dwelling unit;

[0023] FIG. 1J illustrates the completed addition of the extended dwelling unit; and

[0024] FIG. 1K illustrates a detailed view of the removable wall system, detailing the structural elements that comprise the panelized wall system.

[0025] FIGS. 2A-2D illustrate a detailed elevational view of the expandable building system, where:

[0026] FIG. 2A illustrates an elevational view of the rear of an original dwelling unit showing three patch panels attached; and

[0027] FIG. 2B illustrates an elevational view of the rear of the original dwelling unit of FIG. 2A after the patch panels have been removed, revealing a partial wall opening.

[0028] FIG. 2C illustrates an elevational view of the rear of an original dwelling unit with three patch panels attached; and

[0029] FIG. 2D illustrates an elevational view of the rear of the original dwelling unit of FIG. 2C after the patch panels have been removed, revealing a whole wall opening.

[0030] FIG. 3A illustrates a detailed section view of a bracket system and panelized wall design of FIGS. 1A-2D in a disassembled condition; and

[0031] FIG. 3B illustrates a detailed section view of the bracket system of FIG. 3A in an assembled condition.

[0032] FIG. 4A illustrates a detailed section view of an alternative bracket system and panelized wall design of FIGS. 1A-2D in a disassembled condition; and

[0033] FIG. 4B illustrates a detailed section view of the bracket system of FIG. 4A in an assembled condition.

[0034] FIGS. 5A-5I illustrate an alternative process of making a horizontal addition to an existing dwelling unit that was originally built to receive an addition. The process includes the steps of removing a removable wall system, adding an additional room onto an original residential dwelling, and reattaching the removable wall system, where:

[0035] FIG. 5A illustrates an original dwelling unit with the end-cap removed, where corner wall panels are being attached thereto;

[0036] FIG. 5B illustrates the original dwelling unit of FIG. 5A, where brackets are being installed to allow for the reattachment of the end cap;

[0037] FIG. 5C illustrates the original dwelling unit of FIG. 5A where the metal brackets are installed;

[0038] FIG. 5D illustrates the original dwelling unit of FIG. 5A where a full-fall end cap is being attached, thereto;

[0039] FIG. 5E illustrates the original dwelling unit of FIG. 5A with the assembled addition attached, thereto;

[0040] FIG. 5F illustrates a perspective view of the original dwelling unit of FIG. 5A;

[0041] FIG. 5G illustrates a perspective view of the original dwelling unit of FIG. 5A where the bottom corner panel of FIG. 5B is installed;

[0042] FIG. 5H illustrates a perspective view of the original dwelling unit of FIG. 5A where the top corner panel of FIG. 5B is installed; and

[0043] FIG. 5H illustrates a perspective view of the original dwelling unit of FIG. 5A where the end-cap is being installed.

[0044] FIGS. 6A-6E illustrate alternative process of an addition that as comprised of hinged panels which are unfolded on site, where:

[0045] FIG. 6A illustrates an original dwelling unit with and a hinged-panel wall addition system;

[0046] FIG. 6B illustrates the original dwelling unit of FIG. 6A where the hinged-panel wall addition system is unfolded;

[0047] FIG. 6C illustrates the original dwelling unit of FIG. 6A where the hinged-panel wall addition system is fully unfolded and a floor module is being installed;

[0048] FIG. 6D illustrates the original dwelling unit of FIG. 6A where a roof module is being installed onto the unfolded wall addition system; and

[0049] FIG. 6E illustrates the original dwelling unit of FIG. 6A with the fully assembled addition attached, thereto.

[0050] FIG. 7A illustrates an original dwelling unit with a fully-assembled additional room module being attached, thereto; and

[0051] FIG. 7B illustrates the original dwelling unit of FIG. 7A with the fully-assembled additional room module attached.

[0052] FIGS. 8A-13 illustrate wall addition systems and various alternative attachment mechanisms, where:

[0053] FIG. 8A illustrates an interior view of a full wall patch panel system;

[0054] FIG. 8B illustrates an interior view of a partial wall patch panel system;

[0055] FIG. 9 illustrates a patch panel assembly having a cam latch attachment mechanism;

[0056] FIG. 10 illustrates a patch panel assembly having a key attachment mechanism;

[0057] FIG. 11A illustrates a patch panel assembly and a fin attachment mechanism;

[0058] FIG. 11B illustrates the patch panel assembly of FIG. 11A with the fin attachment mechanism attached; and

[0059] FIG. 12 illustrates a patch panel assembly having a pin attachment mechanism.

[0060] FIG. 13 illustrates a patch panel assembly having a bracket attachment mechanism.

[0061] The reader will appreciate the foregoing features and characteristics, as well as others, upon considering the following detailed description of the expandable building system according to this specification.

DETAILED DESCRIPTION

[0062] This specification is generally directed to expandable building systems, and more specifically, removable wall systems for use with modular building structures. However, they are not limited to such extemporary environments.

[0063] Generally speaking, numerous aspects described throughout the specification can be used in the construction of modular structures, prefabricated structures, as well as site-built structures. The removable wall assembly can allow modular structures to grow and expand as well as contrast as the needs of the building owners/occupants change. In one aspect, the removable wall assembly may permit the expansion of a modular residential structure its current footprint to a larger horizontal footprint, for example a rear or side addition that permits additional square footage to be added to the residential structure. In addition, the removable wall assembly may permit a modular residential structure to be contracted and an addition removed, for example when a family is looking to downsize after the children have left the home.

[0064] In other aspects, the removable wall assembly may allow for the replacement of exterior walls on structures designed as permanent buildings. In one aspect, the removable wall assembly may allow a building owner to easily replace the wall structures of a building to update the structural aspects as well as the visual aspect of a building structure. For example, the removable wall assembly may allow for ease of replacing a building with a vinyl siding with one of a wooded siding, a siding of a different color, or another type of exterior appearance, such as brick, or stucco. The ease of removal and replacement with the removable wall assembly can reduce labor costs and replacement wall assemblies can be constructed offsite and shipped to the location of the building which can reduce the time and labor costs associated with replacing a roof structure. Additionally, the removable wall assembly also may facilitate the easy removal and replacement of walls as technology improves and more efficient building materials are produced, such as increased thermal resistivity materials to allow a structure to be more energy efficient or technological upgrades, such as smart panels having built-in electronic features.

[0065] FIGS. 1A-K illustrate the process of removing a removable wall assembly, adding an additional wall panels and horizontal square footage onto an original residential dwelling, and reattaching the removable wall assembly. Referring to FIG. 1A, the original dwelling unit 100 is comprised of four vertical walls, a floor, a roof structure, and a removable wall assembly 110. The removable wall assembly comprises a removable faade 101. FIG. 1B illustrates the faade 101 of the removable wall assembly 110 being removed Arrow A from the original dwelling unit 100. The removable wall assembly 110 further comprises patch panels 103a-c. The patch panels 103a-c can be releasably attached to the original dwelling unit 100 through attachment assemblies 102. Each attachment assembly 102 can comprise an attachment mechanism that permits mechanical attachment of the patch panels 103a-c to the original dwelling unit 100. The attachment assembly 102 also may comprise a quick-connect bracket system that permits the efficient removal of the patch panels 103a-c from the original dwelling unit 100.

[0066] FIG. 1C shows the original dwelling unit 100 with the faade 101 having been completely removed. The original dwelling unit 100 is designed to permit the structure to remain structurally stable with the removal of the removable wall assembly 110, which can allow the internal furnishings and belongings of the occupant to remain in place during the horizontal expansion process.

[0067] Referring now to FIG. 1D, the patch panels 103a-c are shown in the process of being removed Arrow B. The attachment assemblies 102 have been disengaged and the patch panels 103a-c have been released from the original dwelling unit 100. With the removal of the patch panels 103a-c, the original dwelling unit 100 maintains its structural integrity and is now ready for horizontal building expansion.

[0068] FIG. 1E depicts the original dwelling unit 100 with the removable wall assembly 110 (faade 101, patch panels 103a-c, and attachment assemblies 102) removed. With the removable wall assembly 110 removed, opening 104 allows a horizontal addition to be connected to the original dwelling unit 100. FIG. 1F illustrates the horizontal building expansion with the addition of wall panels 105a-d and floor panels 106 being attached Arrow C. The wall panels 105a-d and the floor panels 106 can be attached to the original dwelling unit through an attachment assemblies, similar to attachment assembly 102. When multiple wall panels 105a-d are attached to the original dwelling unit 100, each wall panel 105a-d can be attached to longitudinal walls of the original dwelling unit 100 or to each subsequently added wall panel. Each of the wall panels 105a-d can have an attachment assembly that allows the wall panels 105a-d to be sequentially attached to the original dwelling unit 100 and to each added wall panel. By having a modular building structure with compatible attachment mechanisms, each additional wall panel or floor panel can easily be attached to the original dwelling until 100.

[0069] Referring to FIG. 1G, the wall panels 105a-d and floor panels 106 have been attached to the original dwelling unit 100. In addition, roof assembly 109 has been attached to the original dwelling unit 100 through the use of attachment assemblies that permitted the roof assembly 109 to be easily attached to the original dwelling unit 100. FIG. 1G further illustrates patch panels 103b, 103d, and 103e being attached Arrow F to the original dwelling unit 100. In various aspects, the original patch panels 103a-c may be attached to the original dwelling unit 100 through attachment assemblies 102. In addition, or in the alternative, additional patch panels 103d and 103e can be attached to the original dwelling unit 100. For example, a new patch panel 103d may be attached to the original dwelling unit 100 to add a door access to the original dwelling unit 100. In addition, patch panel 103e may be attached to the original dwelling unit 100 to add a window to the original dwelling unit 100. While the addition of doors and windows are shown during an expansion of the original dwelling unit 100, the patch panels 103d and 103e may be used to replace patch panels or wall panels of an original dwelling unit and allow the occupants to easily add additional windows or doors to the original dwelling unit 100 without the hassle experienced in such an addition in a non-modular structure.

[0070] FIG. 1H illustrates the original dwelling unit 100 with the patch panels 103b, 103d, and 103e attached, which comprise the structural components of the horizontal addition 107. Once the structural components of the horizontal addition 107 have been attached to the original dwelling unit 100, the faade 101 can be attached to the additional wall panels 105a-d and to the patch panels 103b, 103d, and 103e, as shown in FIG. 1I. Where the patch panels are not changed from the pre-expanded original dwelling unit 100, the original faade 101 can be reattached. If the occupant decides to add patch panels having additional features such as doors or windows, new or altered faades 101 can be reattached to the patch panels Arrow G. FIG. 1J illustrates the original dwelling unit 100 with the horizontal addition 107 and additional features of a door and window.

[0071] FIG. 1K illustrates one aspect of the attachment assemblies 102 that allow the horizontal addition 107 to be attached to the original dwelling unit 100. In one aspect, the attachment assembly 102 may comprise a bracket system that allows for the attachment of the components of the horizontal addition to be attached to the original dwelling unit 100.

[0072] Now referring to FIGS. 2A-2D, various aspects of a removable wall assembly 210a-b are shown. FIGS. 2A and 2B illustrate an elevation view of a removable wall assembly 210a having three patch panels 203a-c. The rear wall 218a has a framing 220a which defines an opening 204a. In FIG. 2A, the patch panels 203a-c are attached to the rear wall 218a within partial wall opening 204a. The framing 220 of rear wall 218a provides structural support and does not allow for the entire removal of the rear wall 218a. This orientation is shown in FIGS. 2A and 2B and may be used where the rear wall of a structure is required to be load barring to an extent. Thus, in the aspects show in FIGS. 2A and 2B, the framing 220 of the rear wall 218a allows for the removal of the patch panels 203a-c and the expansion of the original dwelling unit 200. FIG. 2B illustrates the framing 220 of the rear wall 218a of the original dwelling unit 200 with the patch panels 203a-c removed to allow for the horizontal expansion of the original dwelling unit 200.

[0073] FIGS. 2C and 2D illustrate and alternative aspect of a removable wall assembly 210b. The removable wall assembly of FIGS. 2C and 2D allows for the removal of the entire rear wall 218b of the original dwelling unit 200. The removable wall assembly 210b comprises patch panels 203d-f which comprise the entire rear wall 218b of the original dwelling unit 200. As seen in FIG. 2D, when the patch panels 203d-f are removed, the whole opening 204b stretches the entire rear wall 218b and allows for the original dwelling unit 200 to be expanded without having a partial wall opening 204a.

[0074] As see in FIGS. 3A and 3B, an attachment assembly 302 is shown. The attachment assembly 302 can be used to attach addition wall panels, for example wall panels 105a-d to the existing walls of an original dwelling unit 100. In addition, or in the alternative, similar attachment assemblies can be used to attaches floor panels 106 or roof assembly 109 to an original dwelling unit 100, as shown in FIGS. 1A-1K. FIG. 3A shows an attachment assembly 302 in a disassembled condition. The additional wall panels 305 or the walls of the original dwelling unit 300 can include faade 301, sheathing 315, insulation cavity 308 and threaded inserts 312. The additional wall panels 305, and or walls of the original dwelling 100, can comprise a panelized wall system using structural insulated panels (SIPs), traditional lumber framing, or metal studs. The sheathing 315 may provide the structural aspects of the panelized wall system. The additional wall panels 305, and or walls of the original dwelling 100 can be attached to one another through attachment assembly 302. In one aspect, shown in FIGS. 3A and 3B, the attachment assembly 302 can include bracket 322, fasteners 316, fastener openings 324, and weather barrier 304. The weather barriers 304 can be installed between the two conjoining panels during installation between the panels 305 and attachment assembly 302. The weather barriers 304 help ensure that a weather resistant seal is formed between the two wall panels 305. During assembly of the two wall panels to one another, the fasteners 316 releasably attach the wall panel 305, weather barrier 304 and bracket 322. The fasteners 316 can be threaded through the fastener opening 324, engage the weather barrier 304 and are then threaded into the threaded inserts 312. Each of the wall assemblies 305 can be attached to the attachment assembly through the same process and permits expansion of the original dwelling unit 300.

[0075] Now referring to FIGS. 4A and 4B, an alternative attachment assembly 402 is shown. FIG. 4A shows the attachment assembly 402 in a disassembled condition. The wall penalization system depicted in FIGS. 4A and 4B comprise a male-female connection. The wall panels 405 comprise sheathing 415 which provides structural component to the wall panel 405. The sheathing 415 of the female connection portion comprises an opening that allows a corresponding connection portion of the male connector of another wall panel to be inserted and attached. The female connection portion 426 comprises fastener openings 424 that allow fasteners 416 to be threadably passed, therethrough. The attachment assembly comprises two synthetic waterproof membrane weather barriers 404 that are affixed to the female connection portion 426 and the male connection portion 422. Each wall portion 405 comprises an insulation portion 408 on the interior of the sheathing 415 and a faade 401 on the outside of the wall panel 405. The fasteners 416 may be bolts or other types of fasteners. The two adjoining wall panels 405 are attached by inserting the male connection portion 426 of one wall assemble into the female portion 426 of an adjoining wall assembly with the weather barrier 404 therebetween. Once the wall panels are in a mating relationship with one another, the fasteners can be threadably attached through the fastener openings 422 in the female connection 426 and threadably attached to the threaded inserts of the male connection portion 422. FIG. 4B illustrates the attachment assembly shown in FIG. 4A in the attached condition.

[0076] FIGS. 5A-5I illustrate another aspect of an expandable building assembly. FIG. 5A illustrates an original dwelling unit 500 with opening 504 after having removed the faade 501 and patch panels 503, thus exposing the attachment assembly 502. Preassembled corner wall panels 505a-b are in the process of being attached Arrow H. The corner wall panels 505a-b can be assembled on-site or may be assembled off-side and brought to the building site to allow for a more efficient addition building process.

[0077] FIG. 5B shows original dwelling unit 500 with corner wall panels 505a-b attached and additional attachment assemblies 502a-b in the process of being attached Arrow I. The additional attachment assemblies 502a-b may be similar to the attachment assemblies depicted in FIGS. 3A-4B. Once the attachment assemblies 502a-b are attached to the corner wall panels 505a-b, additional corner panels or removable wall assemblies can be attached to the original dwelling unit 500. FIG. 5C shows original dwelling unit 500 with the full wall panels 505a-b and attachment assemblies 502a-b attached, but still without the removable wall assembly 510 attached.

[0078] FIG. 5D illustrates the original dwelling unit 500 with the removable wall assembly 510 being attached to the attachment assemblies 503a, 503b. The removable wall assembly 510 is attached Arrow J and comprises the patch panels 503 and faade 501.

[0079] FIG. 5E illustrates the full addition of the corner wall panels 505a-b and the removable wall assembly 510 attached to the original dwelling unit 500. FIG. 5F is a perspective view showing bottom corner panel 504 in the process of being fastened to attachment assembly 502 lined with synthetic waterproof membrane. FIG. 5G is a perspective view of bottom corner panel 505a affixed to attachment assembly 502a which creates the floor and right side-wall of the addition 507. FIG. 5H is a perspective view of top corner panel 505b in the process of being fastened to attachment assembly 502b which is lined on each side with synthetic waterproof membrane. FIG. 5I is a perspective view of the attachment assembly 502c being attached to the addition 507 and the removable wall assembly 510. A synthetic waterproof membrane in the fastened to the original dwelling unit 500 between the attachment assembly 502c and the corner wall panels to create a weatherproof barrier. Once the structural components of the addition 507 are assembled, the faade 501 of the removable wall assembly can be attached.

[0080] Referring now to FIG. 6A, an alternative horizontal addition assembly is shown. FIG. 6A illustrates an original dwelling unit 600 with the removable wall assembly 610 removed. A hinged wall-panel system 617 is shown. The hinged wall-panel system 617 is in a folded position that can allow for ease of transportation of the hinged wall-panel system 617 to the building site. The hinged wall-panel system 617 comprises an exterior wall 605 having a finished faade 601. Each of the panels of the hinged wall-panel system 617 is connected with a hinge 602. The hinges 619 can comprise different types of hinges, for example a pin hinge, and allow the panels to be folded to allow for ease of transportation and unfolded to permit the hinged wall-panel system 617 to be assembled to the original dwelling unit 600. The attachment interface between the original dwelling unit 600 and the hinged wall-panel system 617 can include a synthetic waterproof membrane to permit the two components to be attached through a weatherproof seal.

[0081] Referring now to FIG. 6B, the hinged wall-panel system 617 is shown in the process of being unfolded. The interior walls 606 of the hinged wall-panel system 617 can be finished interior walls, unfinished interior walls, or partially finished interior walls. FIG. 6C illustrates the hinged wall-panel system 617 fully unfolded. Once the hinged wall-panel system 617 is fully unfolded, the hinges 619 can be locked into position at the respective 90 and 180 degree positions. Once the hinged wall-panel system 617 is unfolded, the floor 608, can be placed within the hinged wall-panel system 617. FIG. 6D shows the hinged wall-panel system 617 with the flooring 608 installed. The roof panel 609 is shown being installed to the addition 607. In the currently aspect, the roof panel measures 1616 and is placed atop the hinged wall-panel system 617. The roof panel 609 and/or the flooring 608 can be delivered to the building site in a singular piece or modular pieces and assembled onsite. FIG. 6E shows the addition 607 fully assembled and attached to the original dwelling unit 600. The addition 607 can be attached to the original dwelling unit 600 through attachment assemblies 602, which are describe in more detail with respect to FIGS. 3A-4B, above, and FIGS. 8A-13, below.

[0082] Referring now to FIGS. 7A and 7B, a fully-built, addition module 707 is shown. The fully-built, addition module 707 may come completely assembled and delivered to a building site or may be built onsite. The fully-built, addition module 707 can be attached to an original dwelling unit 707 using any of the attachment assemblies described herein. FIG. 7A depicts an original dwelling unit 700 with a removable wall assembly removed and a fully-built, addition module 707. FIG. 7B shows the fully-built, addition module 707 attached to the original dwelling unit 700.

[0083] FIGS. 8A-13 illustrate wall addition systems and various alternative attachment mechanisms to permit removable wall assemblies to be removably attached to the original dwelling units 100-1400. The removable wall assemblies described throughout may have different attachment assemblies. The attachment assemblies may allow for the attachment of additional wall panels to the original dwelling units, the attachment of one or more additional wall panels to each other, the attachment of flooring assemblies to the original dwelling unit, the attachment of roof assemblies to the original dwelling unit, and the attachment of removable wall assemblies to any of the aforementioned pieces of the modular building structure.

[0084] Referring to FIG. 8A, an interior view of a removable wall assembly 810 having a full wall patch panel system is shown. The full wall patch panel system comprises patch panels 803a-c. The original dwelling unit 800 can have flooring 806. The patch panels 803a-c can have various attachment locations to the original dwelling unit 800. The patch panels 803a and 803b can be attached to the walls of the original dwelling unit 800 through attachment assemblies 802a and 802d, respectively. In addition, the patch panels 803a-c can be attached to the flooring 806 of the original dwelling unit 800 through attachment assemblies 802g, 802f, and 802e. Patch panels 803a and 803b can be attached to one another through attachment assembly 802b. Patch panels 803b and 803c can be attached to one another through attachment assembly 802c. In addition, the patch panels can be attached to the roofing of the original dwelling unit 800 through similar attachment assemblies. Each of these attachment assemblies can comprise various attachment mechanisms, described in greater detain with respect to FIG. 3A-4B, above, and FIGS. 9-13, below.

[0085] FIG. 8B illustrates an interior view of a partial wall patch panel system. Referring to FIG. 8B, an interior view of a removable wall assembly 910 having a partial wall patch panel system is shown. The partial wall patch panel system comprises patch panels 903a-c. The original dwelling unit 900 can have flooring 906 and rear wall framing 920. The patch panels 903a-c can have various attachment locations to the original dwelling unit 900. The patch panels 903a and 903b can be attached to the framing 920 of the original dwelling unit 900 through attachment assemblies 902a and 902d, respectively. In addition, the patch panels 903a-c can be attached to the flooring 906 of the original dwelling unit 900 through attachment assemblies 902g, 902f, and 902e. Patch panels 903a and 903b can be attached to one another through attachment assembly 902b. Patch panels 903b and 903c can be attached to one another through attachment assembly 902c. In addition, the top portion of the patch panels can be attached to the top portion of the framing 920 of the original dwelling unit 900 through similar attachment assemblies. Each of these attachment assemblies can comprise various attachment mechanisms, described in greater detain with respect to FIG. 3A-4B, above, and FIGS. 9-13, below.

[0086] Referring to FIG. 9, a patch panel 1003 having an attachment assembly 1002 is shown. While the attachment assembly is shown connecting the patch panel 1003 to the flooring 1006 of original dwelling unit 1000, the attachment assembly 1002 can also be used to attach the patch panel 1003 to the walls of original dwelling unit 1000, to the roof structure of the original dwelling unit 1000, to the framing of original dwelling unit 1000, or to additional patch panels. In addition, the attachment assembly 1002 can be used as an attachment assembly to connect other modular structures, described herein. The attachment assembly 1002 comprises a rotatable cam latch 1024 and a cam latch receiver 1022. The cam latch 1024 can be rotated between an attached condition where the cam latch 1024 is releasably attached to the cam latch receiver 1022 to attach the patch panel 1003 to the original dwelling unit 1000 and an unattached condition where the patch panel 1003 is not attached to the original dwelling unit 1000. In the current aspect, the cam latch 1024 is depicted as part of the patch panel 1003 and the cam latch receiver 1022 is depicted as part of the original dwelling unit 1000. However, the reverse configuration is also within the scope of this disclosure.

[0087] Referring to FIG. 10, a patch panel 1103 having an attachment assembly 1102 is shown. While the attachment assembly is shown connecting the patch panel 1103 to the flooring 1106 of original dwelling unit 1100, the attachment assembly 1102 can also be used to attach the patch panel 1103 to the walls of original dwelling unit 1100, to the roof structure of the original dwelling unit 1100, to the framing of original dwelling unit 1100, or to additional patch panels. In addition, the attachment assembly 1102 can be used as an attachment assembly to connect other modular structures, described herein. The attachment assembly 1102 comprises a rotatable key 1124 and a key receiver 1122. The key 1024 can be inserted into the key receiver 1122 and rotated between an attached condition where the key 1124 is releasably attached to the key receiver 1122 to attach the patch panel 1103 to the original dwelling unit 1100 and an unattached condition where the patch panel 1103 is not attached to the original dwelling unit 1100. In the current aspect, the key 1124 is depicted as part of the patch panel 1103 and the key receiver 1122 is depicted as part of the original dwelling unit 1100. However, the reverse configuration is also within the scope of this disclosure.

[0088] Referring to FIGS. 11A and 11B, a patch panel 1203 having an attachment assembly 1202 is shown. While the attachment assembly is shown connecting the patch panel 1203 to the flooring 1206 of original dwelling unit 1200, the attachment assembly 1202 can also be used to attach the patch panel 1203 to the walls of original dwelling unit 1200, to the roof structure of the original dwelling unit 1200, to the framing of original dwelling unit 1200, or to additional patch panels. In addition, the attachment assembly 1202 can be used as an attachment assembly to connect other modular structures, described herein. The attachment assembly 1202 comprises a fin receiver 1224 and a fin 1222. The fin receiver 1224 can receive the fin 1222. During the assembly of the patch panel 1203 to the original dwelling unit 1200, the fin receiver 1224 and the fin 1222 can be aligned. Once the fin receiver 1224 and the fin 1222 are aligned, as seen in FIG. 11A, the fin 1222 can be moved from a recessed position to an extended position, as seen in FIG. 11B and positioned within the fin receiver 1224. Once the fin 1222 is releasable received within the fin receiver 1224, a locking mechanism can be employed to releasable retain the patch panel 1203 to the original dwelling unit 1200. In the current aspect, the fin receiver 1224 is depicted as part of the patch panel 1203 and the fin 1222 is depicted as part of the original dwelling unit 1200. However, the reverse configuration is also within the scope of this disclosure. In addition, the fin may be moved between the recessed and extended positions through a mechanical actuator, a compressed air system, a hydraulic system, a spring system, or a motor driven system.

[0089] Referring to FIG. 12, a patch panel 1303 having attachment assemblies 1302a-c is shown. While the attachment assemblies 1302a-c are shown connecting the patch panel 1303 to the flooring 1306 of original dwelling unit 1300, the attachment assemblies 1302a-c can also be used to attach the patch panel 1303 to the walls of original dwelling unit 1300, to the roof structure of the original dwelling unit 1300, to the framing of original dwelling unit 1300, or to additional patch panels. In addition, the attachment assemblies 1302a-c can be used as an attachment assembly to connect other modular structures, described herein. The attachment assemblies 1302a-c comprise pins 1324a-c and pin receivers 1322a-c. The pins 1324a-c can be received by the pin receivers 1322a-c. During the assembly of the patch panel 1303 to the original dwelling unit 1300, the pins 1324a-c and the pin receivers 1322a-c can be aligned. Once the pins 1324a-c and the pin receivers 1322a-c are aligned, the pins 1324a-c can be moved from a recessed position to an extended position, and positioned within the pin receivers 1322a-c. Once the pins 1224a-c are releasable received within the pin receivers 1322a-c, a locking mechanism can be employed to releasable retain the patch panel 1303 to the original dwelling unit 1300. In the current aspect, the pins 1324a-c are depicted as part of the patch panel 1303 and the pin receivers 1322a-c are depicted as part of the original dwelling unit 1300. However, the reverse configuration is also within the scope of this disclosure. In addition, the pins may be moved between the recessed and extended positions through a mechanical actuator, a compressed air system, a hydraulic system, a spring system, or a motor driven system.

[0090] Referring to FIG. 13, a patch panel 1403 having attachment assemblies 1402a-b is shown. While the attachment assemblies 1402a-b are shown connecting the patch panel 1403 to the flooring 1406 of original dwelling unit 1400, the attachment assemblies 1402a-b can also be used to attach the patch panel 1403 to the walls of original dwelling unit 1400, to the roof structure of the original dwelling unit 1400, to the framing of original dwelling unit 1400, or to additional patch panels. In addition, the attachment assemblies 1402a-b can be used as an attachment assembly to connect other modular structures, described herein. The attachment assemblies 1402a-b comprise fasteners 1424 and brackets 1422a-b. The fasteners 1424 releasable attach the brackets 1422a-b to the patch panel 1403 and the flooring 1406 of the original dwelling unit 1400. The fasteners 1424 can comprise screws, staples, bolts, and/or other types of fasteners.

EXAMPLES

Example 1

[0091] A removable wall assembly for attachment to an exterior wall of a housing unit. The housing unit comprises a first longitudinal wall portion and a second longitudinal wall portion. The first longitudinal wall portion and the second longitudinal wall portion are substantially parallel to one another. The first longitudinal wall portion and the second longitudinal wall portion define an opening therebetween. The opening defines an opening height and an opening width. The removable wall assembly is attached the housing unit and defines a wall structure to fill the opening between the first longitudinal wall portion and the second longitudinal wall portion. The removable wall assembly comprises a patch panel. The patch panel comprises a first vertical side and a second vertical side, wherein the first vertical side and the second vertical side are substantially parallel to one another. The patch panel further comprises a bottom portion and a top portion, wherein the bottom portion and the top portion are substantial parallel to one another. The first vertical side, the second vertical side, the bottom portion, and the top portion are connected to form the patch panel. The patch panel has a patch panel height, a patch panel width, and a patch panel thickness. The patch panel further comprises an attachment mechanism operable between an engaged condition and a disengaged condition. The first vertical side of the patch panel is configured to abut a portion of the first longitudinal wall portion when the patch panel is attached to the housing unit. The bottom potion of the patch panel is configured to abut a portion of a floor system of the housing unit when the patch panel is attached to the housing unit. The attachment mechanism is configured to releasably attach the patch panel to the housing unit when the attachment mechanism is in the engaged condition.

Example 2

[0092] The removable wall assembly of Example 1, wherein the attachment mechanism is configured to releasably attach the bottom portion of the patch panel to the floor system of the housing unit.

Example 3

[0093] The removable wall assembly of Example 1, wherein the attachment mechanism is configured to releasably attach the first vertical side of the patch panel to the first longitudinal wall portion of the housing unit.

Example 4

[0094] The removable wall assembly of Examples 1, 2, or 3, wherein the attachment mechanism comprises a cam latch configured to cammingly engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

Example 5

[0095] The removable wall assembly of Examples 1, 2, or 3, wherein the attachment mechanism comprises a key latch, wherein the key latch is operable between an open condition and a locked condition, wherein the key latch is configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit when the key latch is moved from the open condition to the locked condition.

Example 6

[0096] The removable wall assembly of Examples 1, 2, or 3, wherein the attachment mechanism comprises an attachment pin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

Example 7

[0097] The removable wall assembly of Examples 1, 2, or 3, wherein the attachment mechanism comprises an attachment fin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

Example 8

[0098] The removable wall assembly of Examples 1, 2, or 3, wherein the attachment mechanism comprises an attachment bracket configured releasably attach the patch panel to the housing unit.

Example 9

[0099] The removable wall assembly of Examples 1, 2, 3, 4, 5, 6, 7, or 8, wherein the patch panel defines a first patch panel and wherein the removable wall assembly further comprising a second patch panel. The second patch panel comprises a first vertical side and a second vertical side, wherein the first vertical side and the second vertical side of the second patch panel are substantially parallel to one another. The second patch panel further comprises a bottom portion and a top portion, wherein the bottom portion and the top portion of the second patch panel are substantial parallel to one another. The first vertical side, the second vertical side, the bottom portion, and the top portion of the second patch panel are connected to form the second patch panel. The second patch panel has a second patch panel height, a second patch panel width, and a second patch panel thickness. The second patch panel comprises a second attachment mechanism operable between an engaged condition and a disengaged condition. The first vertical side of the second patch panel is configured to abut the second vertical portion of the first patch panel when the first and second patch panels are attached to the housing unit. The second vertical side of the second patch panel is configured to abut a portion of the first longitudinal wall portion when the second patch panel is attached to the housing unit. The bottom potion of the second patch panel is configured to abut a portion of a floor system of the housing unit when the second patch panel is attached to the housing unit. The second attachment mechanism is configured to releasable attach the patch panel to the housing unit when the second attachment mechanism is in the engaged condition.

Example 10

[0100] The removable wall assembly of Example 9, wherein the top portion of the first patch panel and the top portion of the second patch panel define a removable wall assembly width, and wherein the removable wall assembly width is substantially the same as the opening width.

Example 11

[0101] A method for horizontally expanding a housing unit, comprising the removable wall assembly of Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. The method comprises releasing the patch panel from the housing unit by moving the attachment mechanism from the engaged condition to the disengaged condition. The method further comprises removing the patch panel from the housing unit, installing a horizontal addition onto the housing unit, releasably attaching the addition to the housing unit, and reattaching the patch panel to the horizontal addition by moving the attachment mechanism from the disengaged condition to the engaged condition.

Example 12

[0102] The method of Example 11, wherein the attachment mechanism comprises a cam latch configured to cammingly engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

Example 13

[0103] The method of Example 11, wherein the attachment mechanism comprises a key latch, wherein the key latch is configured to be moved between an open condition and a locked condition, wherein the key latch is configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit when the key latch is moved from the open condition to the locked condition.

Example 14

[0104] The method of Example 11, wherein the attachment mechanism comprises an attachment pin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

Example 15

[0105] The method of Example 11, wherein the attachment mechanism comprises an attachment fin configured to engage a corresponding attachment portion of the housing unit and releasably attach the patch panel to the housing unit.

Example 16

[0106] The method of Example 11, wherein the attachment mechanism comprises an attachment bracket configured releasably attach the patch panel to the housing unit.

Example 17

[0107] A patch panel, wherein the patch panel comprises a first vertical side and a second vertical side, wherein the first vertical side and the second vertical side are substantially parallel to one another. The patch panel further comprises a bottom portion and a top portion, wherein the bottom portion and the top portion are substantial parallel to one another. The first vertical side, the second vertical side, the bottom portion, and the top portion are connected to form the patch panel. The patch panel has a patch panel height, a patch panel width, and a patch panel thickness. The patch panel further comprises an attachment mechanism operable between an engaged condition and a disengaged condition. The first vertical side of the patch panel is configured to abut a portion of a wall portion of a modular housing unit when the patch panel is attached to the modular housing unit. The bottom potion of the patch panel is configured to abut a portion of a floor system of the modular housing unit when the patch panel is attached to the housing unit. The attachment mechanism is configured to releasable attach the patch panel to the modular housing unit when the attachment mechanism is in the engaged condition.

Example 18

[0108] The patch panel of Example 17, wherein the attachment mechanism comprises a cam latch configured to cammingly engage a corresponding attachment portion of a modular housing unit and releasably attach the patch panel to the modular housing unit.

Example 19

[0109] The patch panel of Example 17, wherein the attachment mechanism comprises a key latch, wherein the key latch is configured to be moved between an open condition and a locked condition, wherein the key latch is configured to engage a corresponding attachment portion of a modular housing unit and releasably attach the patch panel to the modular housing unit when the key latch is moved from the open condition to the locked condition.

Example 20

[0110] The patch panel of Example 17, wherein the attachment mechanism comprises an attachment pin configured to engage a corresponding attachment portion of a modular housing unit and releasably attach the patch panel to the modular housing unit.

[0111] Various features and characteristics of removable roof system are described in this specification and illustrated in the drawings to provide an overall understanding of the disclosed apparatus. It is understood that the various features and characteristics described in this specification and illustrated in the drawings can be combined in any suitable manner regardless of whether such features and characteristics are expressly described or illustrated in combination in this specification. The Inventors and the Applicant expressly intend such combinations of features and characteristics to be included within the scope of this specification. As such, the claims can be amended to recite, in any combination, any features and characteristics expressly or inherently described in, or otherwise expressly or inherently supported by, this specification. Furthermore, the Applicant reserves the right to amend the claims to affirmatively disclaim features and characteristics that may be present in the prior art, even if those features and characteristics are not expressly described in this specification. Therefore, any such amendments will not add new matter to the specification or claims, and will comply with written description, sufficiency of description, and added matter requirements (e.g., 35 U.S.C. 112(a) and Article 123(2) EPC). The systems and methods described in this specification can comprise, consist of, or consist essentially of the various features and characteristics described in this specification.

[0112] The examples presented herein are intended to illustrate potential and specific implementations of the present disclosure. It can be appreciated that the examples are intended primarily for purposes of illustration of the disclosure for those skilled in the art. No particular aspect of the examples are necessarily intended to limit the scope of the present disclosure. For example, those skilled in the art will appreciate that the fasteners described herein (e.g., screws) may be replaced or supplemented by other suitable fastening means including a variety of other types of mechanical fastening devices (e.g., nails, rivets, magnets, or others). In another example, a particular choice of construction material (e.g., aluminum, plastic, steel, etc.) may be replaced or supplemented by another type of material which is suitable for the same or similar structure or function.

[0113] Any element expressed herein as a means for performing a specified function is intended to encompass any way of performing that function including, for example, a combination of elements that performs that function. Furthermore the disclosure, as may be defined by such means-plus-function claims, resides in the fact that the functionalities provided by the various recited means are combined and brought together in a manner as defined by the appended claims. Therefore, any means that can provide such functionalities may be considered equivalents to the means shown herein.

[0114] It will be appreciated that, for convenience and clarity of disclosure, terms describing relative orientation or spatial positioning such as proximal, distal, vertical, horizontal, up, down, top, front, back, bottom, upward, or downward may be used at times herein with respect to the drawings and text description in association with various aspects of the disclosure. However, such terms are primarily used for illustrative purposes and are not necessarily intended to be limiting in nature.

[0115] It is to be understood that the figures and descriptions of the present disclosure have been simplified to illustrate elements that are relevant for a clear understanding of the present disclosure, while eliminating, for purposes of clarity, other elements. Those of ordinary skill in the art will recognize, however, that these and other elements may be desirable. However, because such elements are well known in the art, and because they do not facilitate a better understanding of the present disclosure, a discussion of such elements is not provided herein. It should be appreciated that the figures are presented for illustrative purposes and not as construction drawings. Omitted details and modifications or alternative aspects are within the purview of persons of ordinary skill in the art. For example, there may be variations to these diagrams or the operations described herein without departing from the spirit of the disclosure.

[0116] It can be appreciated that, in certain aspects of the present disclosure, a single component may be replaced by multiple components, and multiple components may be replaced by a single component, to provide an element or structure or to perform a given function or functions. Except where such substitution would not be operative to practice certain aspects of the present disclosure, such substitution is considered within the scope of the present disclosure.

[0117] While various aspects of the disclosure have been described herein, it should be apparent, however, that various modifications, alterations and adaptations to those aspects may occur to persons skilled in the art with the attainment of some or all of the advantages of the present disclosure. The disclosed aspects are therefore intended to include all such modifications, alterations and adaptations without departing from the scope and spirit of the present disclosure as claimed.

[0118] Any patent, publication, or other disclosure material identified in this specification is incorporated by reference into this specification in its entirety unless otherwise indicated, but only to the extent that the incorporated material does not conflict with existing descriptions, definitions, statements, or other disclosure material expressly set forth in this specification. As such, and to the extent necessary, the express disclosure as set forth in this specification supersedes any conflicting material incorporated by reference. Any material, or portion thereof, that is incorporated by reference into this specification, but which conflicts with existing definitions, statements, or other disclosure material set forth herein, is only incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. Applicant reserves the right to amend this specification to expressly recite any subject matter, or portion thereof, incorporated by reference.

[0119] The grammatical articles one, a, an, and the, as used in this specification, are intended to include at least one or one or more, unless otherwise indicated. Thus, the articles are used in this specification to refer to one or more than one (i.e., to at least one) of the grammatical objects of the article. By way of example, a component means one or more components, and thus, possibly, more than one component is contemplated and can be employed or used in an implementation of the described processes, compositions, and products. Further, the use of a singular noun includes the plural, and the use of a plural noun includes the singular, unless the context of the usage requires otherwise.