MULTI-STORY BUILDING CONSTRUCTION USING LONG STRAND TIMBER PANELS
Products and methods for constructing mass timber structures in multi-story configurations using long strand timber (LST) engineered wood products. Structural LST panels of predetermined dimensions are fabricated using LST manufacturing methods, typically involving steam pressing a billet of scrimber material that includes treatment materials and bonding material. The long strands of the material used in the panels are oriented vertically for improved load bearing capacity. The panels are sized for shipment to a job site. Prior to shipment, a plurality of panels are pre-processed by cutting openings for windows, doors, tongues, and grooves at a fabrication plant. At the job site, the LST panels are quickly assembled into a building shell (i.e. full exterior walls). Floor and roof joists are then attached using conventional wood fastening devices, and interior build out can commence very quickly after initial construction of the exterior walls.
This application claims benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 62/777,492 filed Dec. 10, 2018, entitled “MULTI-STORY BUILDING CONSTRUCTION USING LONG STRAND TIMBER PANELS”, which is incorporated herein by reference as set forth herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENTNot applicable.
TECHNICAL FIELDThe present disclosure relates in general to building construction, and more particularly relates to construction of multi-story buildings using engineered lumber products formed from long strand timber (LST) as an improved alternative to cross-laminated timber (CLT) or mass plywood panels (MPP).
BACKGROUNDThe information provided below is not admitted to be prior art the present invention, but is provided solely to assist the understanding of the reader.
The building construction industry in the United States and elsewhere in the world is experiencing major changes in how buildings are designed and built. Changes are especially noticeable in the institutional and commercial buildings which traditionally used concrete and steel. Today, mass timber structures are being designed and built into multi-story buildings. “Mass timber structures” are multi-story, multi-unit (multi-family) buildings made from engineered wood products such as Cross-Laminated Timber (CLT) or Mass Plywood Panels (MPP). Mass timber structures may be used to build apartments and condominiums but also can be used to build other multi-story and multi-room buildings for use by professional offices, small retail, and other small business collectives. Proponents of both CLT and MPP technologies have forecast that tall wooden buildings of 20 to 40 stories will be built in the future.
Mass timber structures are increasingly being built in areas where wood products are readily and/or economically available, and where the social climate demands use of renewable or “green” products wherever possible. The currently dominant mass timber structural technology is known as “Cross-Laminated-Timber (CLT) which is an engineered wood product made from layers of dimensioned lumber (e.g. discrete wooden boards or planks) glued at 90 degrees to the adjacent layers and constructed into panels. An exhaustive exploration of CLT as a building option is found in the publication study by Stora Enso, Georg Guntschnig (Project Consultant), “The future of Timber Construction: CLT—Cross Laminated Timber”, Harry Gatterer (editor), published by Zukunftsinstitut Osterreich GmbH (2017).
Another approach to construction of multi-story building is the use of “Mass Plywood Panels” (MPP). MPPs are veneer-based engineered wood products wherein multiple plies of veneer material are glued together into multiple layers, with certain plies aligned long-grain and others cross-grain, with the some and perhaps a majority of the plies in a long-grain orientation for span performance and the cross grain plies to provide minor force direction and panel dimensional stability. MPPs purportedly provide higher recovery of usable fiber than lumber boards used in CLT, and thus have certain potential economic advantages over CLT. Certain information about MPP is found in the presentation by Eric Ortiz, Freres Lumber Co., Inc., “Mass Plywood Panels: Designing with the Newest Mass Timber Structural Product,” delivered to The American Institute of Architects Continuing Education Systems Course, Apr. 20, 2018, found at http://www.woodworks.org/wp-content/uploads/presentation_slides-ORTIZ-Mass-Plywood-Panels-WSF-180425_pdf
Although CLT and MPP may be pioneers in multi-story construction approaches, the materials of both CLT and MPP have certain drawbacks. For one, CLT in particular is made from discrete boards of wood that are formed into a structural unit by gluing. Classically, CLT is a wood panel made from gluing layers of solid-sawn boards of lumber together. Each layer of boards is typically oriented perpendicular to adjacent layers and glued on the wide faces of each board, usually in a symmetric way so that the outer layers have the same orientation, primarily for aesthetic purposes. Typically, a CLT panel constructed in this manner would require numerous consistently sized boards to create the product, which invariably limits the amount of consistent board product that can be obtained and made into a CLT product. This necessarily produces a great deal of waste, as misshapen or improperly sized boards could not be used in a CLT having uniform board properties.
Furthermore, typical CLT requires an internal structural framework for supporting inner and outer boards, which limits the load bearing capacity. For example, a three layer CLT construction having exterior boards oriented horizontally relative to a middle layer, such as for aesthetic purposes, would be limited in longitudinal (vertical) compression strength due to the presence of only a single vertically oriented load bearing layer. Necessarily, the use of alternating layers of vertical and horizontal limits the load bearing capacity.
A MPP is similar to CLT, except that plywood is already made of thin sheets (plies) of wood that are glued together. There is inherent potential for de-lamination of both MPP as well as CLT, as both are made of discrete units of wood product, fastened together with glue only. The structural capabilities of both CLT and MPP would seem to rely heavily on the properties of the glue and its resistance to shear forces, i.e. forces that wold tend to separate the boards or plies. Because of the lack of cross-ply interconnection, both approaches may have more risk of de-lamination because of deterioration as a result of heat or humidity, glue aging or failure, especially when combined with shear forces.
One example of a CLT panel is found in international patent publication to D'Abbadie D'Arras, Michel-Arnaud, WO 2012/149634, “Cross Laminated Timber Panel”. This document describes a cross-laminated timber panel comprising at least a first and a third timber layers each oriented in different directions including at least one timber; at least one second layer laminated with glue between said first and third timber layers comprising at least one layer selected from the group consisting of an insulation layer, a structural layer, a hollow-core or partially hollow-core layer, an insect-resistant layer and a mildew-resistant layer, a fire-resistance layer.
One example of CLT used in multi-story construction is found in international patent publication to Chapman, John Bentley, WO 2015/152735, Auckland Uniservices Ltd., “Cross Laminated Timber Construction”. This document describes a shear core for a building comprising a plurality of laminated timber panels. Each panel has at least one side edge shaped to mesh with a side edge of an adjacent panel, to thereby resist relative vertical movement between the panels. In some embodiments the shear core further comprises at least one stabilizing means associated with a plurality of the panels for preventing movement of the panels out of alignment.
While this approach is useful for some applications, it requires that the side edges be shaped to mesh with corresponding side edges of an adjacent panel. This requires a time- and resource-consuming step of precisely cutting and aligning the mesh of the edges, resulting in wasted product and adding the complexity of the “fit” of the mesh of the panels with each other. Although perhaps structurally desirable, this approach is costly.
Therefore, there is a continuing need for improved timber products for use in multi-story construction.
One particular type of engineered lumber product is believed to be preferable in a number of aspects for use in construction applications where structural strength as well as attractive appearance is important. This advantageous product is the so-called “long strand timber” (LST) product. Such products are shown in U.S. and international patents, owned and/or licensed by TimTek, LLC, for example and not by way of limitation, the following patents, which are collectively hereafter referred to as the “TimTek Patents”:
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- U.S. Pat. No. 6,344,165, Coleman, Manufacture of Reconsolidated Wood Products
- U.S. Pat. No. 4,232,067, Coleman, Reconsolidated Wood Product
- PCT AU87/06437, A Process and Apparatus for Applying Bonding Agent and a Process for Forming Reconsolidated Wood Products
- U.S. Pat. No. 4,695,345, Coleman, Continuous or Semi-Continuous Process for Forming Reconsolidated Wood Products
- U.S. Pat. No. 4,711,689, Coleman, Process for Reconsolidated Wood Production
- U.S. Pat. No. 4,711,684, Coleman, Method and Apparatus for Use in Producing Reconsolidated Wood Products
- U.S. Pat. No. 4,704,316, Grace, Manufacture of Reconsolidated Wood Products
- U.S. Pat. No. 5,279,691, Stickland, Method for Forming a Natural Wood Strand Bundle for a Reconsolidated Wood Product
- U.S. Pat. No. 5,161,591, Sealey et al., Method and Apparatus for Use in Producing Reconsolidated Wood Products
- U.S. Pat. No. 7,537,031, Jarck, A System and Method for the Manufacture of Reconsolidated or Reconstituted Wood Products
- U.S. Pat. No. 7,537,669, Jarck, Systems and Methods for the Production of Steam-Pressed Long Fiber Reconsolidated Wood Products
- U.S. Pat. No. 7,507,360, Jarck, System and Method for the Preservative Treatment of Engineered Wood Products
- U.S. Pat. No. 8,075,735, Jarck, A System and Method for the Separation of Bast Fibers
- U.S. Pat. No. 7,678,309, Jarck, System and Method for the Preservative Treatment of Engineered Wood Products
- U.S. Pat. No. 7,838,446, Jarck, Wood Enhancement Agent Treated Engineered Wood Products
- U.S. Pat. No. 9,931,761, Jarck, Steam Pressing Apparatuses, Systems, and Method
- CA 2,882,607, Improved Steam Pressing Apparatus
- CA 2,272,884, Manufacture of Reconstituted Wood Products
All of the foregoing TimTek Patents, whether owned, or licensed, are incorporated herein by reference as if set forth fully herein, and made a part hereof
BRIEF SUMMARYBriefly described, aspects of the present disclosure provide for products and methods for constructing mass timber structures in multi-story configurations using long strand timber (LST) engineered wood products. Such LST products can readily provide sufficient structural, insulating, aesthetic, and other desirable properties for buildings in the range of four to seven stories, with up to seven stories expected to provide for 75% of the anticipated multi-story construction within the near future. Advantageously, LST products are more cost-effective to fabricate than CLT, are more durable than MPP, have greater load bearing capacity, and are believed by some to be more aesthetically attractive than either.
In accordance with aspects of this disclosure, the LST products are made in accordance with the referenced and incorporated TimTek Patents, and formed into structural panels of predetermined dimensions suitable for shipment to a job site. Preferably, the panels are manufactured with the strands or “scrimber” resulting from the manufacturing process oriented vertically, with long strands being generally parallel, to provide for greater load bearing capacity.
Prior to shipment, a plurality of panels are pre-processed by cutting openings for windows, doors, tongues, and grooves at a fabrication plant, shipped to a job site, and then quickly assembled into a building shell (i.e. full exterior walls) at the job site. Floor and roof joists are then attached using conventional wood fastening devices, and interior build out can commence very quickly after initial construction of the exterior walls.
Generally, in the TimTek Patents, by way of example and not limitation, an engineered long strand timber (LST) or wood product is manufactured by a process involving the crushing of wood logs, which can be of varying lengths, diameters, and tapers, into a mat of what is called “scrim log” material. A scrim log material mat is a mat of crushed log strands from a process as described in certain of the TimTek Patents. The scrim log material mat is formed by processes as shown in the TimTek Patents into a panel of predetermined width, thickness, and length, so as to constitute a long strand fiber panel. Preferably, the long strands in the scrim log material mat are oriented in a direction that will be vertical (along the length of the panel) and therefore load-bearing in the final panels used for a multi-story construction.
According to one aspect, the mat of scrim log material is pre-treated with various materials such as weather-proofing, insect repellent, fire retardant, preservative, or other suitable material to enhance a property of the resultant panels. The mat, after forming into a billet of predetermined size (dimensions) and shape is pressed into a final shape of a panel by a steam press, as also described in the TimTek Patents. After pressing and forming, the long strand fiber (LST) panel is cooled or cured, so that the glue and applied extra treatment materials have sufficiently set and the panel is ready to be used for a building.
After the panels have sufficiently cured, they are pre-fabricated into panels that are specifically configured for a particular construction project, wherein a multi-story building is contemplated. Preferably, the side edges of panels are pre-cut to form a tongue and groove mating engagement, with a tongue on one vertical extending side and a groove on the opposite, vertically extending side. According to one aspect, a groove is formed on the bottom or lowermost edge of a panel, for engaging with a tongue element on a foundational element or a vertically adjacent additional panel. Similarly, a tongue is formed on the top or uppermost edge of a panel, for engaging with a groove element on a vertically adjacent additional panel.
According to one aspect, openings for windows and doors of a building are precut at the factory or fabrication site, so as to minimize the exposure of the panel to the weather for cutting of the openings, and allow pre-treatment of the openings with sealant, preservatives, paint, or the like.
According to one aspect, a plurality of pre-configured panels are delivered to a construction site for a multi-story building, and assembled into the outer or exterior walls of the building at the site. First, the building is initiated by construction of a foundation that preferably includes an embedded tongue element that extends upwardly from the foundation, along the outer periphery of the foundation. Alternatively, a groove element may be provided in the foundation, along the periphery of the foundation, for engaging with a tongue element of a plurality of panels. Suitable panels with mating engagement tongues or grooves are placed into position on the tongue, or groove, as appropriate. A first panel is typically installed as the “anchor” panel, to which the remaining panels for the outer lower wall of the building are engaged and mated. The initial or starter or anchor panel may be supported temporarily with side supports, so as to prevent undesirable lateral, outward or inward non vertical movement, while other and adjacent panels are installed.
The process of installing adjacent panels continues by lowering a next panel into position and engaging both the lower tongue or groove with the foundation element, as applicable and applying horizontal pressure to engage the tongue or groove, as applicable of the two panels that are to reside side-by-side.
It will be understood that prior to engagement of any panels to a foundation element, a tongue or groove of an adjacent panel, a suitable adhesive or other filler material is applied to bond the panels together and to the sideways adjacent as well as lowermost adjacent foundational element or panel. If desired, pressure may be applied to the side edge panel joints, so as to force any excess adhesive from the joint and also to accelerate the curing of the adhesive. Such pressure may be applied by a jack or by use of a hydraulic force applying means such as the bucket of a loader.
Preferably a suitable protective jig is applied to the exposed edge to which pressure is applied to prevent damage to the tongue or groove on the side of the panel to which pressure is applied.
Once a plurality of panels are assembled, leaving typically a single panel opening in the periphery of side walls of a building, the final panel is lowered into position, from an upper position so that the tongue and groove of the final panel is engaged or slid into the tongue or groove, as applicable, of the panels already in place to form the walls with the exception of the final opening. Pressure from the top of the final panel may be needed to cause the final panel to move into position, given that typically adhesive will be applied to the exposed final tongue and groove. In the event of a fit that is less than tight and satisfactory, further pressure may be applied to the overall walls to force the final panel to close any gaps with its adjacent panels, and force the ejection of any excess adhesive materials.
According to one aspect, the exterior wall panels are fabricated such that each of a plurality of panels is configured for a wall portion that extends multiple floors of a multi-story building, with the length of the strands of each panel oriented in the vertical, load-bearing direction, with a plurality of multi-story panels positioned horizontally adjacent one another to form a complete side wall, each panel extending multiple stories of the building.
According to another aspect, the exterior wall panels are fabricated such that each of a plurality of panels is configured as a single-story panel and comprises a wall portion that extends horizontally of a single floor of a multi-story building, with the length of the strands of each panel oriented in the vertical, load-bearing direction, with a plurality of multi-story panels positioned horizontally adjacent one another to form a complete side wall. In such an aspect, each floor of the multi-story building has a plurality of panels extending around the periphery of the floor of the building on a single floor, and each floor has a similar multi-panel assembly of single-story panels.
According to another aspect, an LST floor panel is disclosed, comprising a plurality of relatively thin LST panels that are pressed into a thicker, single, multi-layer floor panel having the length of the strands in one layer oriented at an angle, preferably perpendicularly, to the lengths of the strands in one or more adjacent layers, pressed in the steam press disclosed in incorporated patents of this disclosure, so as to provide a multi-layer floor panel that can be assembled with other, like floor panels to make floors for use in a building construction as described herein. The multi-layer floor panels are pre-fabricated and delivered to a construction site, as for the exterior wall panels, and assembled on site into a completed, multi-floor building.
According to yet another aspect, a multi-story building can be constructed with vertical support columns that are made from LST material pressed in the steam press disclosed in incorporated patents of this disclosure, with the long strands of the LST material oriented in a vertical, load-bearing orientation, to provide vertical support as well as aesthetically attractive features for exterior columns, floor support columns, decorative columns, and the like. According to another aspect, a larger billet or slab of LST material can be prefabricated and cut either on-site or at the fabrication plant into smaller, discrete, individual support columns.
The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
Turn now to the drawings, which accompany the following detailed description and illustrate various aspects, embodiments, features, and elements of the claimed inventions and the context for the use thereof. While exemplary embodiments and aspects are described herein, it will be understood that various modifications to the methods and devices can be made without departing from the scope of the present invention, which are solely limited by the appended claims. For example, the size, shape, position, materials, and other aspects of the described structural panels may vary from those illustrated in a number of ways. Furthermore, the sequential recitation of steps in any claim is not a requirement that the steps be performed in any particular order, unless otherwise so stated.
The following is a description of certain non-limiting preferred embodiments and/or aspects of the claimed invention. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments and/or aspects of the invention described herein. Those of ordinary skill in the art will appreciate that various changes and modifications to this description may be made without departing from the spirit or scope of the present invention, as defined in the claims that are appended following this description.
Turning now to the drawings, in which like numerals indicate like elements or components or structure or context throughout the several views,
Each panel 12 is preferably a long strand timber (LST) panel fabricated according to the teachings of one or more of the incorporated TimTek Patents. These panels are initially formed from a solid billet of scrimber material, as described in such patents, into a predetermined standard or uniform size, prior to making any cutouts for doors, windows, tongues, grooves, or other material removal for architectural and/or design purposes. A primary consideration for the size of the panels 12 is the steam press that is used to form the panels from the billets of scrimber material that have been initial fabricated with appropriate selected adhesive, fire retardant, insect treatment, or other material, prior to introduction to the steam press in accordance with various of the incorporated TimTek Patents. According to an aspect of this disclosure, wall panels that are 40-50 feet long by 4-6 feet wide by 5-8 inches thick, or within a reasonable variation of those dimensions, are suitable for making the wall panels, floor panels, and column panels as disclosed herein.
It will be understood from the incorporated TimTek Patents that such patents describe systems and methods for the manufacture of steamed-pressed long fiber reconsolidated wood products, which are suitable for use as the panels 12 as described herein. The systems and methods in such patents typically comprises a bonding agent application system for applying bonding agent to a scrim log material mat that can be formed into the panels 12. The bonding agent application system further comprises a roller mechanism, wherein the roller mechanism is configured to compress the scrim log material mat in order to further open any fissures or cracks within the scrim log material mat in order to aid in the uniform application of the bonding agent onto the scrim log material mat. The resultant mat is of a shape and size corresponding to the raw (uncut) panels prior to pressing in a steam press.
In accordance with aspects of this disclosure, the LST products are made in accordance with the referenced and incorporated TimTek patents, and formed into structural panels of predetermined dimensions suitable for shipment to a job site. Preferably, the panels are manufactured with the strands or “scrimber” resulting from the manufacturing process oriented vertically, with long strands being generally parallel, to provide for greater load bearing capacity.
It will be further understood from the TimTek patents that the described systems and methods comprise a steam press chamber that is configured to release a predetermined volume of steam into the steam press chamber in order to cure the bonding agent that has been applied to the scrim log material mat. The steam press chamber further comprises a pressing mechanism, wherein the pressing mechanism is configured to compress the scrim log material mat to a predetermined thickness, height, width, and density corresponding to the size of the panels 12.
In particular, an apparatus such as that shown in U.S. Pat. No. 9,931,761, the disclosure of which is incorporated by reference herein as if the same were fully set forth herein, may be used to construct the long strand timber panels according this this disclosure. The steam pressing apparatus as described in the incorporated patent generally comprises a substantially rectangular or square-shaped inner chamber (such as an autoclave) and an outer, generally rectangular or square-shaped structure. The steam pressing apparatus comprises a hydraulic system used to compress and treat a working material with high efficiency, timing and precision. In one aspect, the steam pressing apparatus comprises a structure and system that allows modularity and scalability for manufacturing final products of varying dimensions, for example the long strand timber panels described herein. Advantageously, such a steam pressing apparatus can be designed to respond to computerized instructions relating to the pressure to be applied, steam to be applied, vacuum parameters, timing of the press operation, thickness of the resultant working material, and other informational inputs, so as to provide an end product that is suitable for constructing multi-story buildings as described herein.
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Each panel 12 is shown in
It will be appreciated that the described tongue and groove edge elements, as well as the doors, windows, or other openings into a panel 12 are preferably pre-cut by use of a computer numerical control (CNC) router preprogrammed for the openings required for each of a plurality of panels intended for use in a building construction.
In accordance with aspects of the invention and this disclosure, the panels 12 are preferably prefabricated solid LST panels all of the same length, width, and height for efficiency of manufacturing. At a factory, based on a design plan (not shown), cutouts for doors and windows are made prior to shipment. The pre-cut panels for an entire building may be pre-cut and sent to a job site, where the building can be quick assembled and roofed in, so as to prevent weather damage and facilitate drying-in for interior work.
The panel 12 in
As shown in
Although the disclosed embodiment and aspects involves a tongue and groove configuration for adjacent panels 12, it should be understood that other attachment or placement methods may be used to secure adjacent panels in a building construction. For example, a butt joint type engagement could be employed, as well as interlocking joints formed by CNC at the fabrication plant. It will be appreciated that a tongue and groove configuration, as well as an interlocking configuration, provides more surface area for glue, e.g. at least double the glue surface compared to a butt joint. It will be further appreciated that an interlocking configuration is more costly from a CNC routing perspective, and may be a more delicate structure at more risk to damage during assembly.
The panel 12 in
In accordance with aspects of this disclosure, the appropriate tongue(s) 24 and groove(s) 26, whether side edge or top or bottom edge, are milled or routed from a fresh panel 12, at a fabrication plant, prior to shipment to a job site and assembly. Preferably, tongues, grooves, doors, and windows are pre-cut at the fabrication plant so as to minimize exposure of the panels to the elements at the job site. It will of course also be appreciated that pre-fabrication of the discrete panels for a particular designed building makes the eventual assembly quicker at the job site.
In accordance with an aspect of the disclosure, a retaining plate or “dagger” 35 is provide to engage with the foundation 20 and with a panel 12, to provide a way to bolt down and hold the panels in position and resist shear and inward compression/wind load forces. A retaining plate or dagger 35 may be made of metal such as steel or aluminum. The retaining plate 35 may be rectangular as shown, or may be of other desired shape. The retaining plate is preferably embedded into the concrete of the foundation 20 at the pour. In this manner, the retaining plate distributes forces within the foundation. Alternatively, the retaining plate 35 could be made L-shaped and fastened to the fountain 20 with a concrete bolt or other fastening mechanism. As shown in
It will be appreciated that the retaining plate 35 is shown in
It will be appreciated that preferably the groove is filled or coated with a suitable filler material such as adhesive or sealant or grout, both on the bottom groove and the side edge, to hold the panels together for structural integrity and strength. Alternatively, the tongues may be coated with such adhesive or sealant, prior to engagement. After placement of a panel 12, preferably side pressure is applied to force any excess filler material out and seal the joint securely. Side pressure may be applied with a hydraulic jack or a machine such as a bucket loader, provided of course that suitable protection for the side edge is provided to prevent damage to the tongue or groove. If desired, an elongate protection jig (not shown) having a first surface for engaging with the tongue or groove and a second surface for engaging with a pressure-applying device such as hydraulic jack or bucket loader may be constructed and utilized, to provide a mechanism against which pressure can be applied and distributed along the entire side edge, for uniform pressure.
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As in the multi-story panels 12 of
As with other LST panels as disclosed herein, the floor panels 90 are preferably provided with tongues and grooves on opposite side edges to provide for shear and compression resistance at the joints between panels or mounting. The tongues and grooves are not necessarily the same dimensions as those of the thicknesses T1, T2 . . . TN, and can be cut out to a preferred dimension. Similarly, the thicknesses of the layers T1, T2 . . . TN need not necessarily to be uniform.
According to one aspect, the panels 12, 80, 90 are treated at initial fabrication for outdoor use. Such treatment may include incorporation of insecticide or insect repelling materials, e.g. to repel or discourage termites. Such treatment may include sealing or weatherproofing on the exterior surfaces. Such treatment may also include a fire retardant material.
It will be appreciated that a building constructed in accordance with this disclosure will exhibit excellent insulating properties. With the panels being dense in constitution and in the realm of 6 inches thick and used as exterior walls, they can be expected to provide a high “R” insulation rating.
It will also be appreciated that construction elements such as wall panels (multi-story as well as single-story), floor panels, and vertical support beams constructed with the long strand timber (LST) material as disclosed herein and described in the incorporated TimTek patents, being a species of oriented strand lumber (OSL), exhibit minimal creep when deployed in a building construction, and are believed to satisfy the requirements of current structural standards including ASTM D 5456, Standard Specification for Evaluation of Structural Composite Lumber Products, which includes laminated veneer lumber (LVL), parallel strand lumber (PSL), laminated strand lumber (LSL), and oriented strand lumber (OSL), and ASTM D 6815, Standard Specification for Evaluation of Duration of Load and Creep Effects of Wood and Wood-Based Products.
From the foregoing, it will now be appreciated that the use of LST products for multi-multi-story building construction provide a better alternative in many respects to either CLT or MPP. The LST products and panels are engineered from low-cost small timber and thinnings, which lowers the cost of the end LST product without compromising structural integrity, susceptibility to weather or insect damage, fire resistance, etc. as well as aesthetics and attractiveness in appearance that is attractive to architects. And, such materials are considered renewable and “green”, as well as minimize the waste that can occur in particular with CLT. A LST construction panel as described herein provides extremely stiff and dense panels that can be 4 feet wide, 40 feet long and 6 to 8 inches thick, and capable of bearing the load of multiple floors. The panels can be treated “in process” of panel formation for weather durability, termite, woodborer and other insect protection and fire retardation. Furthermore, the LST engineered wood panels are less at risk of delamination due to the intertwined fiber strands in the LST product. Both CLT and MPP are believed to be at greater risk of delamination in humid climates as compared to LST material.
With use of the LST panels and construction methods as described herein, multi-story buildings of 4 to 6 stories can be quickly constructed, it is believed in a few days using only 4-5 workers and a small crane capable of lifting the 40×4 foot panels that are considered a preferred configuration.
It is further believed that use of LST panels as described herein can be half the cost of CLT methods, because of the use of the long strand timber method which can use smaller logs of varying diameters and lengths, whereas the CLT approach in particular depends on uniform board length to provide an attractive product.
In the claims that follow, articles such as “a”, “an”, and “the” may mean one or more than one unless indicated to the contrary or otherwise evident from the context. Claims or descriptions that include “or” between one or more members of a group are considered satisfied if one, more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process unless indicated to the contrary or otherwise evident from the context. The invention includes embodiments in which exactly one member of the group is present in, employed in, or otherwise relevant to a given product or process. The invention also includes embodiments in which more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process.
Furthermore, it is to be understood that embodiments of the invention encompasses all variations, combinations, and permutations in which one or more limitations, elements, clauses, descriptive terms, etc., from one or more of the claims or from relevant portions of the description is introduced into another claim. For example, any claim that is dependent on another claim can be modified to include one or more limitations found in any other claim that is dependent on the same base claim. Furthermore, where the claims recite a composition, it is to be understood that methods of using the composition for any of the purposes disclosed herein are included, and methods of making the composition according to any of the methods of making disclosed herein or other methods known in the art are included, unless otherwise indicated or unless it would be evident to one of ordinary skill in the art that a contradiction or inconsistency would arise. In addition, embodiments of the invention encompass compositions made according to any of the methods for preparing compositions disclosed herein.
Where elements are presented as lists, e.g., in Markush group format, it is to be understood that each subgroup of the elements is also disclosed, and any element(s) can be removed from the group. It is also noted that the term “comprising” is intended to be open and permits the inclusion of additional elements or steps. It should be understood that, in general, where the invention, or aspects of the invention, is/are referred to as comprising particular elements, features, steps, etc., certain embodiments of the invention or aspects of the invention consist, or consist essentially of, such elements, features, steps, etc. For purposes of simplicity those embodiments have not been specifically set forth in haec verba herein. Thus for each embodiment of the invention that comprises one or more elements, features, steps, etc., the invention also provides embodiments that consist or consist essentially of those elements, features, steps, etc.
Where ranges are given, endpoints are included. Furthermore, it is to be understood that unless otherwise indicated or otherwise evident from the context and/or the understanding of one of ordinary skill in the art, values that are expressed as ranges can assume any specific value within the stated ranges in different embodiments of the invention, to the tenth of the unit of the lower limit of the range, unless the context clearly dictates otherwise. It is also to be understood that unless otherwise indicated or otherwise evident from the context and/or the understanding of one of ordinary skill in the art, values expressed as ranges can assume any subrange within the given range, wherein the endpoints of the subrange are expressed to the same degree of accuracy as the tenth of the unit of the lower limit of the range.
In addition, it is to be understood that any particular embodiment of the present invention may be explicitly excluded from any one or more of the claims. Any embodiment, element, feature, application, or aspect of the compositions and/or methods of the invention can be excluded from any one or more claims. For purposes of brevity, all of the embodiments in which one or more elements, features, purposes, or aspects is excluded are not set forth explicitly herein.
Claims
1. A multi-story building comprising:
- a plurality of prefabricated long strand timber (LST) engineered wood panels, each panel having at least one side edge shaped to engage with a side edge of an adjacent panel, to thereby resist relative vertical movement between the panels;
- each LST panel having a length, a width, and a thickness, and having a vertically extending attachment edge extending along each vertically extending side edge of the panel,
- each LST panel comprising pre-cut openings for windows and doors;
- each LST panel comprising a linearly extending first engagement structure along a vertically extending side edge of the panel and a complementary linearly extending second engagement structure extending along the other and oppositely disposed vertically extending side edge of the panel, wherein the first engagement structure is configured to engage with a second engagement structure of an adjacent panel,
- wherein each of the LST panels comprise a cured, long strand timber material that is formed in a steam press from a scrimber material into a panel of predetermined length, width, and thickness.
2. The multi-story building of claim 1 wherein the strands of each LST panel are oriented in a vertical direction to provide for load bearing capacity.
3. The multi-story building of claim 1 wherein the side edges are tongue and groove.
4. The multi-story building of claim 1 comprising a filler material between the side edges of adjacent panels.
5. The multi-story building of claim 1 wherein the filler material is an adhesive, a sealant, a spline.
6. The multi-story building of claim 1 wherein a plurality of the panels are arranged side by side.
7. The multi-story building of claim 1 wherein the panels are arranged such that the lower edges of alternate panels are at substantially the same height.
8. A multi-story building comprising:
- a plurality of long strand timber panels, each panel having at least one side edge connected to a side edge of an adjacent panel, the connection between the panels being adapted to resist relative vertical and horizontal movement between the panels;
- wherein the panels are pre-cut at a fabricating plant prior to shipment to a job site to provide for doors and windows and side edge attachment elements, and a foundation for supporting at least one row of said panels along a periphery to form the exterior walls of the building.
9. The multi-story building of claim 8, wherein the strands of long strand timber panels are oriented vertically for load bearing capacity.
10. A method of manufacturing a multi-story building, the method comprising the steps of:
- i. providing a first long strand timber (LST) panel having at least one side edge;
- ii. providing a second LST panel having at least one side edge adjacent the first LST panel, such that a side edge of the first panel is adjacent, but spaced apart from, a side edge of the second LST panel;
- iii. introducing a filler material into a space between the side edges of adjacent LST panels; and
- iv. pressing the adjacent panels into close proximity to each other to eject excess filler material, and
- v. continuing the placement of LST panels until forming a complete exterior wall of the building.
11. The method of claim 10, wherein the strands of each LST panel are oriented vertically for load bearing capacity.
12. The method of claim 10 wherein each said LST panel includes a tongue or groove attachment element on each side and top edge.
13. The method of claim 10 wherein the filler material comprises an adhesive.
Type: Application
Filed: Dec 9, 2019
Publication Date: Jun 11, 2020
Inventor: Walter Jarck (Clarkesville, GA)
Application Number: 16/708,235