Strapping System and Method to Reinforce Framed Structures

Abstract

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; and   fastening the tensioned straps to the structure.   
   
   
       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, and   a 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; and   a means for joining and tensioning each matching auxiliary top runner and foundation strap;   a means for permanently securing the tensioned straps together; and   fastening 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.