Patent application title: Strapping System and Method to Reinforce Framed Structures
David J. Fannon (Daphne, AL, US)
Johnny R. Cahoon (Daphne, AL, US)
IPC8 Class: AE04G2300FI
Class name: Static structures (e.g., buildings) vertical structure with brace, or guy, extending diagonally to a base
Publication date: 2010-02-25
Patent application number: 20100043315
Patent application title: Strapping System and Method to Reinforce Framed Structures
David J. Fannon
Johnny R. Cahoon
MARK O. LOFTIN
Origin: MOBILE, AL US
IPC8 Class: AE04G2300FI
Patent application number: 20100043315
A network of straps is placed over a framed structure and roof decking and
secured to the foundation. A tensional force is applied to the straps.
The tensioned straps are then secured at strap crossing points, the roof
decking, roof structural members and wall structural members. The method
also provides special treatment for straps crossing apex ridges or
valleys of the structure's roof. Additional framing blocks are included
under the roof decking to accommodate fastening the straps to the primary
structural members. The runner straps pass through slits cut into roof
decking near where the sidewalls attach to the roof joists and rafters.
An added framing member or supporting structural device is also installed
above the top plate of the stud wall to support the roof decking as
tension is applied to the straps. The method calls for determining
standard strap spacing based on the design resistance required to counter
external forces that could be encountered at the construction location.
The straps are placed on all sides at the standard spacing. Special
adjustments to the spacing are made to accommodate larger than standard
spacing door, garage, and framed openings. The number and configuration
of straps is dependent on Building Codes and engineered design
guidelines. By securing the strap network to the structure under tension,
the strap network provides a distributed resistance force throughout the
entire structure greatly enhancing its strength against external winds,
internal vacuums, and earthquakes. Suitable straps can be fabricated from
range of materials and composites such as metallic and non-metallic
banding, a combination of non-metallic banding with wire reinforcement,
wire mesh or wire rope.
1. A reinforcing system for increasing a framed building's structural
resistance to forces generated by winds, sudden movements, and sudden
pressure drops comprising:a plurality of parallel runner straps placed at
minimum spaced horizontal distances over the roof decking of the
structure and extending downward along two opposite side walls of the
structure;a plurality of matching parallel foundation straps placed at
the same spaced distances as the runner straps and secured on both ends
to the structure's foundation;a means for joining and tensioning each
matching runner and foundation straps;a means for permanently securing
the tensioned straps together; andfastening the tensioned straps to the
2. The structural reinforcing system of claim 1 where the fastening of the tensioned straps to the structure occurs where the runner straps intersect with the roof trusses, apex ridge, rafters and wall studs.
3. The structural reinforcing system of claim 1 applied to a 4-sided structure where a second plurality of perpendicular runner straps is placed at minimum spaced horizontal distances over the roof decking of the structure and extending downward along the two other opposite side walls of the structure intersecting the first plurality of runner straps at right angles.
4. The structural reinforcing system of claim 2 where one or more fasteners are placed through the straps and into roof structural members at each point where the perpendicular straps intersect the parallel straps.
5. The structural reinforcing system of claim 1 where the runner and foundation straps are fabricated from steel having a width of from 0.5 inch (12.7 mm) to 4.0 inches (101.6 mm) inclusive and a thickness of 10 standard gauge (0.1382 inch or 3.5 mm) to 32 standard gauge (0.0134 inch or 0.34 mm) standard gauge inclusive.
6. The structural reinforcing system of claim 1 where the runner and foundation straps are fabricated from the non-metallic group consisting of polyethylene, polypropylene, polyvinylchloride, polyethylene nylon, fiberglass, Kevlar, and dynema.
7. The non-metallic straps of claim 6 where the straps have a width of from 0.25 inch (6.35 mm) to 4.0 inches (101.6 mm) inclusive and a thickness 0.250 inch (6.35 mm) to 0.003 inch (0.076 mm) inclusive.
8. The non-metallic straps of claim 6 where the straps further contain one or more metallic wires embedded or woven into the non-metallic material for purposes of reinforcement.
9. The structural reinforcing system of claim 1 where the minimum spaced horizontal distance of the top and bottom straps is between 3 and 12 feet inclusive.
10. The structural reinforcing system of claim 1 where a strap that crosses a roof rafter, a fastener is applied through the strap, through the roof decking and into the structural member.
11. The structural reinforcing strap of claim 1 where a strap that crosses a roof valley is secured to the roof through a plurality of fasteners placed through the strap into a metal plate placed underneath the roof decking and on both sides of the roof valley.
12. The structural reinforcing strap of claim 1 where a strap that crosses a roof valley is secured to the roof through a plurality of fasteners placed through the strap and into blocks placed underneath the roof decking and on both sides of the roof valley.
13. The structural reinforcing system of claim 1 where the structure has an eave, the plurality of parallel top straps extend downward along the side walls through slits cut into the roof decking such that the straps are flush with the outside face of the structural wall.
14. The structural reinforcing system of claim 13 where a support member is placed on top of the wall and under the roof decking to prevent compression of the roof decking when tension is applied to the strap.
15. The structural reinforcing system of claim 1 where the protected structure has 2 or more stories and includes a second roof structure extending below the upper roof and away from the outside wall of the higher structure, the system further comprises a plurality of parallel auxiliary runner straps placed at the same horizontal spacing distances as the top runner straps over the upper roof structure and over the lower roof decking,said auxiliary top runner straps connected on one end to the corresponding downwardly extending top runner straps after the top strap is tensioned, and a second end extending downward along outer side wall of the second roof structure, anda plurality of matching parallel auxiliary foundation straps placed at the same spaced distances as the auxiliary top runner straps and secured on one end to the structure's foundation; anda means for joining and tensioning each matching auxiliary top runner and foundation strap;a means for permanently securing the tensioned straps together; andfastening the tensioned straps to the roof structural members, through the roof decking, at points where the roof structural members and the strap network intersect;
16. The structural reinforcing system of claim 1 where the structure has an apex roof, further comprising a runner strap that crosses the roof apex, the runner strap is fastened to the roof decking and apex structural roof member at the point of apex.
17. A method of reinforcing a structure to improve resistance to lateral and vertical forces acting upon it from sources such as hurricanes, tornados and earthquakes, comprising the steps of:determining a standard strap spacing dimension based on the degree of structural resistance desired,marking a grid pattern on a plan view drawing of structure with the grid spacing equal to the standard spacing dimension desired,where a grid line intersects a door, window or other opening in the side wall of the structure, move the interfering end of that grid line to the edge of the opening,installing a plurality of foundation straps with one end firmly secured to the structure's foundation at each point where the grid lines cross the external face of the structure,installing a plurality of runner straps over the top of the structure along the grid lines with each runner having one end extending down along the side wall stud and meeting a matching foundation strap at the structure's bottom and having a second end extending down along the opposite side wall stud and meeting a matching foundation strap at the structure's bottom,installing a fastener through each runner strap into the roof decking and structure at each place where the runner crosses a structure's roof valley,joining each end of a runner strap to its matching foundation strap applying a standard tension to the joined straps,secure the tensioned straps to the roof decking and the roof and wall structural members.
CROSS REFERENCE TO RELATED APPLICATIONS
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
BACKGROUND OF THE INVENTION
The present invention relates to devices and methods for improving the resistance of a structure to lateral and vertical forces acting upon it. The most common sources of lateral and vertical forces acting on a structure are weather phenomena such as hurricanes, tornados, microbursts, etc. and earthquakes. Without some type of reinforcement means, most structures have relatively poor inherent resistance and are subject to significant damage from such events. For example, strong winds blowing into the sidewall of a structure will exert lateral and oblique forces against the wall and also upward forces on the roof as the forces accumulate and strengthen at building indentions, corners and roof eaves. Exterior framed structure finish veneers such as brick and concrete stucco provide mass and some resistance to lateral wind forces. Other finish veneers such as vinyl siding, EIFS and lap siding provide negligible resistance to lateral wind forces above that resistance provided by the framed structure itself. Interiors and structures are often damaged from the separation of roof decking from framing members. Wood, the most common framed structure building material, has relatively poor tensile strength. Most jurisdictions require compliance with a Building Code. Building Codes define the minimum level of structural reinforcement required to maintain structural integrity when subjected to external forces deemed possible to occur in that local area. Numerous devices and methods have been devised to improve structural resistance for use with framed structures. All of these methods and devices are designed to keep the structure intact during a violent event to maintain integrity of the structure but the devices consistently use the wood structural members for intermediate tensional resistance within the overall reinforcement concept. None of the existing concepts or devices addresses the overall structure and roof decking by connecting all of the structural and decking components with one network system that allows the entire structure and the individual components to act together to counter external forces.
FIELD OF THE INVENTION
In general, the local Building Code (or "Code") will dictate which methods of structural reinforcement must be applied. These requirements will vary depending on the most likely event and external forces that could occur to the structure. For example, in the Gulf Coast region of the United States where hurricanes are relatively common, structural reinforcement systems typically consist of bolting or attaching wall reinforcement devices along with rafter straps or cabling, etc. attached at various points onto the framed structure. All of these reinforcements are designed to keep the roof rafters and wall studs tethered to the structure's foundation using the wood structural members as intermediate components of the concept. Codes in other areas subject not to hurricanes but to other potential external forces typically have different reinforcing methods and devices.
Although the devices of the previous examples have generally good individual component yield strength and can protect against separation of the contacting structural members, they provide minimal protection for the overall structure and no protection for the plywood roof decking covering the structure. As a result, when the weakest part of the structure or the roof decking is compromised, significant damage to the structure and contents occurs from rain and wind forces. Secondly, these devices that use wood as the intermediate tensional members are generally not capable of withstanding very strong wind events and many structures are still damaged each year.
What is needed in the art is a cost-effective means for protecting the integrity of the roof decking while at the same time, substantially increasing the resistance of the entire framed structure and decking to separation.
What is also needed in the art is a means for dramatically improving the strength of a framed structure without requiring a substantive change to the method or materials of construction.
What is also needed in the art is a standardized, engineered solution that differentiates varying external forces and prescribes standard components in varying ways to protect an entire framed structure and all components including wall sheathing and roof decking.
BRIEF SUMMARY OF THE INVENTION
The present invention is a reinforcing system applied to an entire structure that when installed, greatly increases the structure's resistance over prior methods yet can be applied affordably. The principal behind the present invention is that, when interconnected, a series of binding elements is stronger than that of each individual element attached at various points in a framed structure. An additional principal is that the framed structure is being structurally reinforced without using framed members having low tensile strength as part of the reinforcement system. The invention is comprised of plurality of strapping elements placed on top of the roof decking of a structure, extending down the side walls of the structure, and attached to the structure's foundation. Each strapping element is tensioned after being set in place. Once all of the strapping elements are in place and tensioned, the straps are secured to the structure at various locations and at points where the straps intersect. Once fastened together, the straps form an extremely strong web of reinforcement throughout the entire the structure. Resistance to wind loads, for example that may be applied to only one side of the house are actually spread throughout the entire structure due to the network of interconnected straps. Thus, the structure's integrity cannot be lost by the failure of any one element as is typical with devices that are attached at various points in a framed structure.
The present invention is an engineered product, which means that the number of straps, location of the straps, and the fastening points to the structure must be determined by a trained person for each particular structure and the Building Code requirements for the area where the structure is located. In general, the more straps and the more fastening points, the greater the overall network resistive strength will be achieved. To assist in understanding the methodology of applying this system, a four-sided structure is used. However, one skilled in the art can apply the basic principals of the 4-sided structure example to cover other structural layouts.
The basic element of the system is the strap. Each complete strap is comprised of two "foundation" straps and a "runner" strap. Each foundation strap has one end embedded into or otherwise attached to the structure's foundation. The other end of the foundation strap is connected to one end of the runner strap. The runner strap is placed up the outside of the sidewall, through a slit in the roof decking, up over the top of the roof decking, and down the opposite side wall. One end of the runner strap is connected to the foundation strap without tension using various metal strapping means. Using a standard strap-tensioning tool, the end of the opposite foundation strap is set into the device and the opposite end of the runner strap (coming down from above) is set into the device. The device is ratcheted to pull the runner and foundation straps together to a prescribed minimum tension. Once under tension, the pieces are attached together and the tensioning device is removed. Once all of the straps are tensioned, the straps are "networked" by fastening them at various points to the roof structure and at strap crossing points.
It is an object of the invention to provide a structure stabilizing system that includes a plurality of interconnected, pre-tensioned straps.
It is a further object of the invention to provide a structure stabilizing method that presents a simple approach to designing and installing a network of interconnected, tensioned straps to accommodate a wide range of building types, sizes and roofing configurations.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a three-dimensional view of a four-sided structure with a typical strapping design that includes examples of methods for larger than standard openings and a framed attachment to the main structure.
FIGS. 2A, 2B and 2C show types of foundation sections of various strap assemblies, which are embedded into the foundation's slab or stemwall foundation.
FIGS. 3A, 3B and 3C show alternate embodiments of foundation sections and various strap assemblies where the structure does not have a concrete slab such as found with structures built on pilings or piers.
FIGS. 4A and 4B show an alternate embodiment of a foundation section where one end is attached to an anchor bolt as might be done for retrofit applications or interior wall anchors.
FIG. 5 shows a side cross-sectional view of a strap where it exits the top of the roof decking and extends below the decking, down the sidewall of the structure.
FIGS. 6C-6D show various pre-tensioning roof attachments for situations such as roof valleys.
FIGS. 6A-6B show various post-tensioning roof attachments for situations such as roof apexes.
FIGS. 7A, 7B show typical attaching means for securing various types of tensioned straps to the roof structural members.
FIGS. 8A, 8B and 8C show details of various runner strap sections.
FIG. 9A-9J show details of typical joining methods for runner and foundation sections of the various straps that can be used before and after applying tension using a tensioning tool.
DETAILED DESCRIPTION OF THE INVENTION
In reference to FIG. 1, a standard 4-sided structure with an angled roof and eave is shown with the strapping system of the present invention in place. Item 1 represents the standard strap spacing determined by the installer based upon the degree of resistance desired or required by local Building Codes. The inventors have determined that 3 to 10 feet spacing will be adequate for most Code requirements and external forces to be expected in the United States. The shorter the standard spacing, more straps will be present for a given building dimension and greater structural resistance will result. For example, 3-feet spacing may be required to protect a structure directly on the coast, which may be subject to the highest wind force of a hurricane. However, greater standard spacing may be desired further inland as hurricane winds tend to decrease once the storm moves further over land.
The strapping system of this typical structure is designed by first locating the end-wall strap spacing 7 placed within a minimal distance from the outside wall corner. Then, moving toward the opposite wall, the next strap is placed at the standard spacing 1 except when interferences occur. This procedure is repeated for the other two walls resulting in a grid-type layout over the structure. The straps that are placed on standard dimensions that extend down over an opening into the structure's wall, such as a door or window, are then moved according to several standard adjustment formulas. Straps that interfere with openings may be spaced closer than standard as shown by spacing 5. The inventors set forth herein the preferred adjustment means for the most typical of structural openings. The methodology behind these formulas are exemplary and can be applied to other wall openings as well.
The first adjustment formula applies to a window opening 4 that is greater than the standard spacing dimension determined for the structure. In this instance, one end of the strap is placed on the edge of the window opening while the other end of that strap is located at the next forward strap location. A second strap is located on the other edge of the window opening with the other end extending to the preceding adjacent strap location. The strap spacing on the wall opposite the wide window 4 is maintained at standard spacing 1. This design formula results in these two adjacent straps forming an "x" pattern 9 over the structure whereas most other straps between two opposite side walls will be parallel. The "x" pattern 9 allows multiple connections to roof structural members, providing greater overall strength, as the runner strap passes over these structural members on a diagonal.
A second adjustment formula is applied to a garage opening 6 where the opening dimension is more than 2-times the standard spacing dimension. In this instance, a standard spacing dimension 1 is marked on the opposite wall from garage bay opening having a center located directly across from the opening's center. One strap is located on one edge of the garage bay and extends over to the structure's roof to 11. A second strap is located at the other edge of the garage bay and extends over the structure's roof to 12. Additional straps that are located at the garage opening edge run directly across the roof structure and connect to foundation straps on both ends. All four garage bay edge straps are connected with fasteners to the horizontal opening structural member. A third strap is secured to the horizontal structural member at the center of the garage opening and extends directly across the roof structure to the opposite sidewall. This design formula results in these two adjacent straps forming an "x" pattern 8 over the structure with a third strap centered in between.
In continued reference to FIG. 1, an entrance-way appurtenance 15 is shown on the forward wall. This typical entrance-way is comprised of a 3-sided structure and covering roof extending away from the main 4-sided structure of the building. Straps 14, which secure the main structure are connected to the foundation and extend down the outside wall of the main structure, behind the wall of the entrance-way appurtenance 15. This entrance-way appurtenance 15 is reinforced by a single strap 10 placed over the appurtenance roof near the forward edge. The purpose of placing this appurtenance strap close to the edge is the separation of the appurtenance's roof structure from the stud wall is most likely to happen from vertical forces pushing up on the forward eave of the appurtenance. Therefore, the tie-down force should be applied as close to the forward wall edge as practical to secure that area. Longer appurtenances may be secured with more than one strap. Chimney and porch appurtenances are also secured in a similar manner.
As a practical matter, the location and placement of the straps are typically performed graphically by an architect or engineer with strap spacing adjustments made for openings in the side walls. Once the initial structural grid and sidewall opening adjustment formulas have been applied, a drawing is marked and given to field personnel to begin marking the foundation structure at the determined locations and installing the foundation straps.
In reference to FIGS. 2A, 2B and 2C, an embodiment of a foundation section is shown for new construction applications. This foundation strap is further comprised of an embedding section 20 and an attachment section 21. The embedding section of a metal strap or bracket 20 is typically coated with a material that prevents corrosion by the concrete material of the foundation slab 22. This section is also bent at various locations to form a general "hook" shape that provides increased strength of attachment once embedded into cured concrete. An additional area of the metal portion of the strap base 21 approximately 18'' above the embedded portion is coated to prevent any moisture below grade or weeping from the wall or mortar from a brick wall system degrading the strap strength. A metal strap will have holes along its length suitable for nails, screws, bolts, or other fasteners to attach the strap to framing members to secure the strap at critical framing changes or unusual structural components. The attachment metal section 21 may have two additional small holes 24 located near the first bend for proper positioning and insertion of nails or other fasteners to secure the strap to the concrete form. The metal strap has additional holes that allow the strap to be easily attached to the bottom wall plate and to the wall stud 23 and further secure the wall structure to the foundation. The attachment strap section need only be a few feet long and can be coiled up and set on the ground until the framing crews complete the basic wall and roof structure construction. FIG. 2C shows an alternate embodiment of the foundation section using a non-rigid strap material. To facilitate positioning and shaping of the non-rigid material during installation, a rigid bracket 31 is used with the flexible strap material to hold the strap at the proper shape when the foundation is poured.
In reference to FIGS. 3A, 3B and 3C, an alternate embodiment of a foundation section of a strap assembly is shown for structures without a concrete slab. The foundation strap 3B is also further comprised of a foundation section 20 and an attachment section 21. The foundation section 20 contains two pairs of holes 26 for receiving a pair of securing bolts or other type fastener. This foundation section is bent at two locations to form a general "U" shape of width 28 that conforms to the supporting structure 25 dimensions. The attachment section 21 has holes located along its length for insertion of nails or other fasteners to secure the strap to the bottom plate and wall stud 23 and further secure the wall structure to the supporting foundation structure. The foundation strap 3C made from alternate materials would require a rigid bracket base section 31 similar to strap 3B to reinforce the attachment to the foundation. The attachment section need only be a few feet long to provide a working length for attachment to the matching strap runner coming down the sidewall from above.
In reference to FIGS. 4A and 4B, an alternate embodiment of a foundation section of a strap assembly is shown for retrofit applications to existing slabs or for anchoring interior wall straps. This type of foundation strap is field fabricated from a runner strap and has a short end piece bent at 90° and has a central hole for attachment to a standard concrete anchor 29. The central hole in the strap is placed over the threaded end of the concrete anchor 29 and the nut fastener with washer is attached.
Once all of the foundation straps are in place at the locations determined by the system design and framed construction is complete to the point of roof decking and outer walls, the matching runner straps are installed over the roof decking of the structure and extended down the sidewall of the structure through the roof decking. In reference to FIG. 5, a typical strap routing is shown for a structure with an eave extending out away from the wall stud. In this case, a slit 50 is cut into the roof decking flush with the outside edge of the wall stud 23. To avoid compression of the roof decking when the straps are tensioned, a framing block 52 is inserted underneath the roof decking behind the strap and secured to structural members. One end of the runner strap 53 is inserted through the slit 50 and extended down far enough to reach the matching foundation strap at the base of the wall stud.
After the straps are placed over the roof decking and extended down the sides of the stud walls, just prior to joining and tensioning the runner and foundations strap sections, certain runner straps must be anchored. Primarily, these include runner straps crossing roof valleys.
FIG. 6C shows a securing system for a typical roof valley 69 employing a formed sheet metal frame 64 that is inserted around the valley structural member 69. The formed frame employs two flat sections abutting the underside of the roof decking on either side of the valley. A hole is drilled through the roof decking and a pair of bolt-type fasteners 62 are inserted and tightened, which secures the strap in 3 places across the gable. FIG. 6D shows an alternate valley-securing system comprised of a central bolt 65 securing the strap to the valley structural member and a pair of screw type fasteners 66 securing the strap to the roof decking and framing blocks 67 underneath the roof decking on either side of the roof valley.
Once the valleys are secured, the straps are ready to be tensioned. From the ground around the structure, the installer joins one end of the runner strap to its related foundation strap by any number of standard metal strapping means. The installer then inserts the opposite loose end of the runner section into a common strap-tensioning tool. The loose end of the foundation strap is also inserted into the strap-tensioning tool. The straps are then pulled together to provide a permanent tension force to the entire runner/foundation strap. The inventors estimate that 50-200 ft-lbs of tension would be adequate for most applications although more or less tension could be applied in special circumstances. A "proper tension-over tension" gauge is used to determine that minimum tension has been reached while also confirming that the strap has not been over tensioned. The uniformity of tension levels through the strap network insures proper performance of each strap. The gauge will be incorporated into each strap at the tensioning location and remain visible for inspection. While under tension, the runner and foundation straps are connected together by any number of standard metal strapping attachment means. When valley points are secured on a roof, the tensioning and joining must take place at both ends of the runner and foundation straps ground locations.
Once the individual straps are tensioned, the system is networked together by fastening the runner sections together at crossing points and fastening the runner sections to the structure. In general, the more fastening points of the tensioned strap network to the structure, the greater reinforcement properties of the system. The critical attachment points to the structure are the roof apex ridge, roof rafters and wall studs. The installer will typically apply structural fasteners into the roof decking at every point where two or more straps overlap. FIG. 1 shows a typical attaching point 13 where two perpendicular straps intersect. The fastener is installed through the straps and into the roof decking. FIG. 7A shows a typical fastener 70 installed through the strap, through the roof decking, and into the roof rafters. FIG. 7B shows an attaching means for two straps that intersect between two adjacent roof rafters. The bolt or other similar fastener 71 is inserted through the straps at the point of intersection, through the roof decking and through a framing block 72 placed between and secured to the roof structure. Additional fasteners will then be installed where straps cross roof rafters and apex ridges. The most basic attachment means involves the use of a screw or nail 60, as seen in FIG. 6A, that secures the strap to the apex structural member 68. An alternate attachment means can be a bolt and nut assembly 61, as shown in FIG. 6B. The bolt is inserted through a hole in the strap and extending through the apex structural member 68. A nut is then placed on the end of the bolt and tightened. Still more fasteners will be installed on the vertical part of the runner straps securing the strap to the top and bottom plates and vertical studs. Fasteners may also change depending on the strap material. For example, a non-rigid metallic steel mesh or nylon strap would not have pre-drilled holes in the strap material. These type straps would be fastened to the roof decking and rafters using screws with washers.
FIG. 8A shows the detail of a metal runner section 80 of a strap having a width 83 and a plurality of pre-drilled holes 84, spaced apart a distance 82, and spaced from the strap's edge a distance 81. Metal straps are typically made of 10 to 32 gauge galvanized steel of width between 0.5 to 4.0 inches. As a general matter, different steel compositions and heat treating operations will be used to provide stronger straps. Also the wider and thicker the strap, the greater will be the yield strength and the stronger the individual strap and the network strength. The pre-drilled holes allow for rapid installation of fasteners by the installer. The holes are offset a distance 81 from the side at least 1/4'' to maintain strength of the attachment. The holes 84 are spaced apart a distance 82 of approximately 1-2 inches. The holes 84 are staggered to allow more variety of location and improve the number of points where the holes align over the roof and wall structural members. Coating methods, such as galvanizing, may be applied to metal strapping in specific climate zones where air contaminants could cause corrosion and degradation of the strap material. Non-corrosive metal materials such as stainless steel of varying grades may be utilized in more corrosive atmospheres.
FIG. 8B shows the detail of a non-metallic plastic, fabric or other non-metallic material runner section 80 of a strap having a width 83. Non metallic straps are typically made of plastics and fabrics made of nylon, fiberglass, Kevlar, dynema, polyethylene, polypropylene, polyvinylchloride or similar materials and having the ability to be formed by extrusion or woven into a strap formation. The strap would have a width between 0.5 to 4.0 inches and thickness between 3 mil (0.003 inches) and 250 mil (0.250 inches). As a general matter, different non-metallic materials or combinations of non-metallic materials in a matrix may be used to provide stronger straps. Also the wider and thicker the strap, the greater will be the yield strength and the stronger the individual strap and the network strength. Connection points of the strap and the network into the roof and wall structural members is easier with non-metallic straps as the penetration at any point through the strap does not require pre-punched holes. Metal reinforcing washers and brackets at certain attachment positions would be required to reinforce those attachment points when utilizing non-metallic straps.
FIG. 8C shows the detail of a non-metallic plastic, fabric or other non-metallic materials runner section with integral wire reinforcement 85 of a strap having a width 83. Wire reinforced non metallic straps or wire mesh or rope straps are typically include plastics and fabrics made of nylon, fiberglass, Kevlar, dynema, polyethylene, polypropylene, polyvinylchloride or similar materials and having the ability to be formed by extrusion or woven and include within the extruded or woven strap formation also includes a matrix of wires of various metallic materials. The percentage of metallic wires could increase to 100% of this embodiment to manufacture a strap totally of wires formed in a mesh or rope that then could be flattened for suitable installation on the vertical wall and across the roof decking of a framed structure and not interfere with the installation of other overlapping components such as wall siding or roofing shingles. The strap would have a width 83 between 0.25 to 4.0 inches and a final installed thickness between 3 mil (0.003 inches) and 250 mil (0.250 inches). As a general matter, different non-metallic materials or combinations of non-metallic materials plus more metallic wire reinforcement may be used to provide stronger straps. Also the wider and thicker the strap, the greater will be the yield strength and the stronger the individual strap and the network strength. Connection points of the strap and the network into the roof and wall structural members is easier with wire mesh, wire rope or wire reinforced non-metallic straps as the penetration at any point through the strap does not require pre-punched holes. Metal reinforcing washers and brackets at certain attachment positions would be required to reinforce those attachment points when utilizing straps incorporating these materials.
There are several methods suitable for joining the runner and foundation straps before and after applying tension. The tensioning tool pulls the straps along side each other until the correct tension is established. In FIG. 9A, a crimping and folding tool cuts a plurality of notches 90 through both straps and bends the notched strap material over and compresses the metal together. The notches are rotated 180 degrees to provide attachment resistance in multiple directions.
FIG. 9B shows an alternative attaching means using a banding strap 91 that is inserted over the tensioned straps and crimped using a special tool. Multiple banding straps are applied to ensure a strong connection. FIG. 9C shows an additional attachment means employing a buckle 92. The end of each strap is threaded through the buckle holes and aligned. When axial tension is applied, the friction caused by contact between the straps and the buckle metal will hold the straps together. FIG. 9D shows an additional attachment means comprised of a plurality of fasteners, such as bolts or rivets, 93 inserted into overlapping straps 80. The holes in the two straps are aligned and the fasteners inserted and secured. FIG. 9E shows an alternative fastener embodiment where screws 94 are used to secure straps 80 into a cross beam 96 inserted and secured between to wall studs 95. FIG. 9F shows an alternate attaching means employing an adhesive 96 placed between the straps that once cured forms a strong bond between the straps. FIG. 9G shows an alternate attaching means comprised of a mesh sock 98 into which both ends of the runner and foundation straps are placed. When axial tension is applied to the mesh sock, a proportional gripping force is applied to the inserted strap ends holding them together. FIG. 9H shows an alternate attaching means comprised of a tension buckle 99 with hooked ends that are inserted into holes on the straps. When connected, the tension buckle is turned. By screw action, each hook end is pulled toward the buckle center applying tension to the straps. FIG. 9I shows an additional attachment and tensioning means employing a ratcheting turnbuckle 100. Each end of the straps is inserted into a slot located in the center barrel of the turnbuckle. As the turnbuckle is ratcheted, the center barrel turns, wrapping the straps from different directions and pulling the straps together. Once the desired tension is applied, a set pin is positioned to keep the center barrel immobile and the turnbuckle ratchet handle is moved to the rest position. FIG. 9J shows an additional attachment using a sleeve 101 that is placed around the straps 80 to be joined that includes one or more set-screws 102 that are threaded into and secure the two internal straps by pressure of the sets screws against the straps and the sleeve base.
Patent applications in class VERTICAL STRUCTURE WITH BRACE, OR GUY, EXTENDING DIAGONALLY TO A BASE
Patent applications in all subclasses VERTICAL STRUCTURE WITH BRACE, OR GUY, EXTENDING DIAGONALLY TO A BASE