The present invention is directed to a flashing for use on a roof valley.
Many buildings include multiple roof sections that are at angles with respect to each other and that intersect. The joint at which two roof sections intersect at a peak or point is often referred to as the roof “ridge.” The concave joint between two roof sections is often referred to as a valley. Roof valleys typically encounter high water loads because the valley collects water running off of two roof sections.
The roof sections are typically covered by a plurality of shingles, and on many roofs, a valley flashing component is installed at the valley joint where the use of shingles is not a practical option. The valley flashing runs along the valley joint and shingles are layered on top of it. The purpose of the valley flashing is to provide increased protection against water infiltration at the valley joint. Without proper sealing of the valley joint, water can seep underneath the roof shingles and cause rot and deterioration of the roof decking and rafters.
Traditional valley flashing designs suffer from notable drawbacks. First, in geographical areas in which stormy, windy weather is common, water can be forced far enough under the shingles that are layered over the edge of the valley flashing and can then reach the roof material under the shingles and flashing. High winds, which are often accompanied by rain, can lift parts of the shingles and allow blown rain to move between the shingles and the flashing.
Next, valley flashing is often made of metal, which can act as a lightning rod. The metal valley flashing can attract lightning, which, when it occurs, can destroy the structure to which the flashing is attached. Metal flashing also presents difficulties in joining multiple pieces to cover a long valley joint. Joining a number of individual flashing components together to cover a valley joint are typically requires sealing with caulk, for example, silicone caulk. Caulked joint seals have a limited lifespan before they degrade and cause the seal to fail. Seal failure requires expensive repair or it can cause water leaks and, eventually, rot.
Traditional valley flashing is typically installed by applying a fastener, such as a nail, directly through the flashing itself and into the roof decking. This has some notable disadvantages. First, it creates an opening through the flashing through which water can reach the roof decking. Second, it eliminates the ability of the installer to make adjustments to the positioning of the flashing as he or she is installing the shingles over the edge of the flashing.
Accordingly, what is desired is valley flashing that provides improved protection of a roof valley joint from water intrusion, particularly in geographical areas subject to intense storms. Further, what is desired is a valley flashing that is resistant to degradation over time. Even further, what is desired is a valley flashing that is easier and less cost intensive to manufacture, install, and maintain.
It is an object of the present invention to provide improved protection of a roof valley joint from water intrusion.
It is a further object of the present invention to provide a valley flashing device that is resistant to degradation over time, even when it is exposed to elements such as wind, rain, and sunlight.
It is yet a further object of the present invention to provide a valley flashing that is easier and less cost intensive to manufacture, install, and maintain.
According to a first embodiment of the present invention, a roof valley flashing device is provided, comprising: a first roof panel comprising a first upper surface and a first lower surface; a second roof panel arranged at a first angle with respect to said first panel and comprising a second upper surface and a second lower surface; and a first attachment flange extending from the first lower surface of the first roof panel.
In some embodiments, the device further comprises a second attachment flange extending from the second lower surface of the second roof panel. In some embodiments, the device further comprises a longitudinal axis; and a first protrusion having substantially the shape of a “T” when viewed along the longitudinal axis, and arranged on the first upper surface. In some embodiments, the device further comprises a second protrusion having substantially the shape of a “T” when viewed along the longitudinal axis, and arranged on the second upper surface.
In some embodiments, the device further comprises a third protrusion arranged on the first upper surface, the third protrusion extending at an angle toward a center of the device. In some embodiments, the device further comprises a fourth protrusion arranged on the second upper surface, the fourth protrusion extending at an angle toward the center of the device. In some embodiments, the device further comprises a middle portion that connects the first roof panel and the second roof panel.
In some embodiments, the middle portion is shaped and the first and second roof panels are arranged such that the device has substantially the shape of a “W” when viewed along the longitudinal axis. In some embodiments, each of the first and second roof panels are joined to the middle portion by a curved corner. In some embodiments, the third protrusion is disposed on the first upper surface between the first protrusion and the middle portion, and the fourth protrusion is disposed on the second upper surface between the second protrusion and the middle portion.
In some embodiments, the device further comprises a fifth protrusion arranged on the first upper surface adjacent to the third protrusion and extending at an angle toward the center of the device; and a sixth protrusion arranged on the second upper surface adjacent to the fourth protrusion and extending at an angle toward the center of the device.
In some embodiments, the first roof panel further comprises a first upper edge and a first lower edge and the second roof panel further comprises a second upper edge and a second lower edge; and the first attachment flange extends from the first lower surface at the first lower edge and the second attachment flange extends from the second lower surface at the second lower edge.
In some embodiments, the device is comprised of a flexible, plastic material. In some embodiments, the device is formed by an extrusion process.
According to a second embodiment of the present invention, a roof valley flashing device is provided, comprising: a longitudinal axis, a first roof panel comprising a first upper surface, a first upper edge, and a first lower edge; a second roof panel arranged at a first angle with respect to said first panel, and comprising a second upper surface, a second upper edge, and a second lower edge; a middle portion connected to the first lower edge and to the second lower edge; a first protrusion having substantially the shape of a “T” when viewed along the longitudinal axis, and arranged on the second upper surface; and a second protrusion having substantially the shape of a “T” when viewed along the longitudinal axis, and arranged on the second upper surface. The first protrusion is located between the first upper edge and the first lower edge of the first roof panel and the second protrusion is located between the second upper edge and the second lower edge of the second roof panel.
In some embodiments, the device further comprises a first attachment flange extending from the first lower surface of the first roof panel and a second attachment flange extending from the second lower surface of the second roof panel. In some embodiments, the device further comprises third and fourth protrusions disposed on the first upper surface between the first protrusion and the first lower edge, the third and fourth protrusions extending toward a center of the device. In some embodiments, the device further comprises fifth and sixth protrusions disposed on the second upper surface between the second protrusion and the second lower edge, the fifth and sixth protrusions extending toward the center of the device.
According to a third embodiment of the present invention, a roof valley flashing device is provided, comprising: a longitudinal axis, a first roof panel extending along the longitudinal axis and comprising a first upper surface, a first upper edge, and a first lower edge; a second roof panel extending along the longitudinal axis and arranged at a first angle with respect to said first panel, and comprising a second upper surface, a second upper edge, and a second lower edge; a middle portion connected to the first lower edge and to the second lower edge; at least one first tab disposed on the first roof panel, extending substantially parallel to the longitudinal axis and angled toward a center of the device; and at least one second tab disposed on the second roof panel, extending substantially parallel to the longitudinal axis and angled toward the center of the device.
In some embodiments, the middle portion is shaped and the first and second roof panels are arranged such that the device has substantially the shape of a “W” when viewed along the longitudinal axis. In some embodiments, the device further comprises a first attachment flange extending from the first lower surface of the first roof panel and a second attachment flange extending from the second lower surface of the second roof panel.
In some embodiments, the device further comprises a first protrusion having substantially the shape of a “T” when viewed along the longitudinal axis and arranged on the second upper surface; a second protrusion having substantially the shape of a “T” when viewed along the longitudinal axis, and arranged on the second upper surface; and the first protrusion is located between the first upper edge and the first lower edge of the first roof panel and the second protrusion is located between the second upper edge and the second lower edge of the second roof panel.
Exemplary embodiment(s) of the invention will now be described in greater detail in connection with the following drawings.
The figures show certain embodiments of the present invention having a variety of features. It will be understood by those of skill in the art that not all of the features of each embodiment depicted or described are necessarily present in other possible embodiments of the invention.
The valley flashing 10 shown in
The valley flashing 10 also includes two sets of wind tab protrusions. Wind tab protrusions 20 and 21 are disposed on the upper surface 16 of the first roof panel 11, while wind tab protrusions 22 and 23 are disposed on the upper surface 17 of the second roof panel 12.
The valley flashing 10 shown in
In the embodiment of
The wind tabs 20, 21, 22, and 23 are designed to be disposed under the roof shingles 33. In the embodiment shown, the tabs are flexible, so that they bend downward toward the surface of the roof panels when the shingles are installed on top of the tabs. In some embodiments, the flashing 10 has only a single wind tab in or around the position of the tabs 20, 21, 22, and 23 shown in the Figures. The wind tabs help prevent water from migrating up and under the shingles. This protects the roof decking 31a and 31b from water damage. In the embodiment shown, the wind tabs project from the upper surfaces 16 and 17 at angles other than 90 degrees. Advantageously, the tabs are arranged at an angle such that they point toward the center of the flashing. For example, tabs 20 and 21 are angled with respect to the upper surface 16 such that they extend toward the middle of the flashing. This feature that the tabs are angled toward the middle of the flashing is achievable using a variety of angles. These include angles less than 90 degrees as shown in the figures, 90 degrees, and even greater than 90 degrees, so long as the extension of the tab is in the direction of the center of the flashing. In the particularly advantageous embodiment shown, the tabs are angled toward the opposite roof panel, which requires a more acute angle than a tab that extends only toward the center of the flashing.
In the embodiment shown in
In some embodiments, the flashing 10 is secured to the roof by attachment fasteners through the flanges 24 and 25 and then nails are used to secure the shingles 33, some of which are also driven through the flashing 10. In such embodiments, then, only the nails through the flanges 24 and 25 secure the flashing alone. In other embodiments, additional fasteners driven through the roof panels 11 and 12 are used to secure the flashing 10 to the roof. This is not always the optimal installation process, however, as it requires more fasteners than other techniques.
In the embodiment shown, the valley flashing 10 is formed of a flexible, resilient material. Material of this type permits the “T” protrusions and wind tabs to flex underneath the shingles and provide a seal. In the embodiment of the invention shown in the figures, the flashing 10 is constructed of a polymer plastic material. The flashing, including the roof panels, middle portion, and protrusions, is a single unitary piece. In an advantageous embodiment, the flashing is extruded by a melt extrusion process. As is known in the art, such a process generally involves melting raw plastic pellets and forcing the melted plastic through a die. The extrusion product is then cooled so that it hardens into the shape created by the die. Flashing made by this method can be made into virtually any desirable length. Other suitable manufacturing processes are employed in other embodiments, such as injection molding.
The material used in the most advantageous embodiments of the present invention is flexible and completely waterproof. The most advantageous polymers for this application do not degrade significantly with time. Such advantageous polymers include additives to increase the material's resistance to breakdown due to exposure to ultraviolet (UV) light.
In the advantageous embodiment shown in the figures, the flashing is constructed using a polypropylene-based composition in the thermoplastic elastomer olefinic chemical family. The composition includes polypropylene, a styrene ethylene butylene styrene copolymer, calcium carbonate, antioxidant/stabilizer, and mineral oil. A colorant is also added to provide the desired appearance of the flashing and to enhance the UV breakdown resistance of the flashing. Pigments and other fillers are generally encapsulated in the resin so as to avoid any hazardous conditions when the material is processed.
The embodiment of the flashing shown in the figures is made using a material that will not show evidence of visible cracks after exposure to ozone pressure of 100 mPa and a temperature of 104° F. for 70 hours, pursuant to ASTM Standard D1149-12. Further, the material used in the embodiment of the figures will not show appreciable change in mass or volume after submersion in distilled water at a temperature of 158° F.±2° F. for a minimum of 46 hours, pursuant to ASTM Standard D471-06. Specifically, the material will have a percent change in mass and volume of about 0.00%, respectively.
The material used in the embodiment of the figures also meets the AC286 Section 4.4 standard using the ASTM Standard D412-06 tensile strength and elongation procedure even after weathering for 2000 hours in accordance with ASTM G154. Specifically, the average ultimate elongation of the weathered material exceeds the minimum of 210 percent under SC286 Section 4.4 and the minimum of 85 percent under AC286 Section 4.7 with respect to control specimens. Even more specifically, the material has an average tensile strength of 1530 psi before weathering and an average tensile strength of 1490 psi post-weathering. The material has an average elongation percent of 472% before weathering and 427% post weathering.
The tear strength of the material used in the embodiment of the figures exceeds the minimum of 1.43 pounds per inch pursuant to AC286 Section 4.5 and ASTM Standard D624-12. Specifically, the material has an average tear strength of 733 pounds per inch.
The material used in the embodiment of the figures does not show signs of cracking or brittleness when tested at −40° C. in accordance with AC286 Section 4.6 and ASTM Standard D2137-11. Furthermore, the material meets the tensile strength and elongation requirements of AC286 Section 4.7 even after exposure to Ultra Violet radiation pursuant to ASTM Standard G154-06. In other words, its average ultimate elongation percent exceeds 85% of the average elongation percent of the control specimens.
Advantageously, the material of the embodiment of the flashing shown in the figures is selected to expand and contract in concert with the expansion and contraction of the other building materials around the flashing, such as the roof decking, rafters, shingles, siding, etc. This minimizes the effects of such expansion and contraction on the seals between sections of flashing and the overall strength of the flashing.
A further advantage of embodiments of the present invention that are formed of the above-described polypropylene-based composition is that the flashing does not conduct electricity like traditional, metal flashing. Traditional metal flashing can attract lightning due to its conductivity. Embodiments of the present invention that are formed of certain polymer plastic materials, such as the above-described polypropylene-based composition, have negligible conductivity. The result is that roofs that use such embodiments of the present invention instead of metal flashing are far more resistant to lightning strikes or other electrical damage.
Another advantage of this embodiment of the present invention is that a single piece of flashing can be used along an entire length of the valley joint even as the length exceeds multiple feet. As a result of its construction using a polymer and the extrusion technique, the flashing can be made in a much greater length than traditional flashing. As such, the flashing of this embodiment of the present invention requires far fewer joints between pieces of flashing. When a joint is required, the two pieces of flashing can be joined by the technique of heat welding using a piece of polymer of the same or similar composition. This heat-welded joint remains strong and watertight much longer than a caulked joint between metal flashings. The heat-welded joints require less maintenance and have a much lower risk of failure than traditional caulked joints. As those of skill in the art will appreciate, caulking is an inexact science. Once caulk loses its adhesion to a surface, it can act as a siphon and draw water in. For some installations, some portions of the protrusions on the flashing 10 (such as the “T” protrusions and wind tabs) are trimmed by the installer to permit two pieces of the flashing to overlap and be welded together. In other embodiments, two sections of overlapping flashing can be joined in a permanent, bonded relationship using an approved sealant. Such a sealant may fuse the two sections together permanently as if they had become a single, continuous section.
The flexibility of the flashing according to the exemplary embodiments shown in the figures also improves the ease and quality of the installation. The flexible flashing is better able to adapt to variations in the roof decking and rafters. This improves the waterproofing function of the valley flashing.
It will also be understood that patching or repairing the flashing of the illustrated embodiments of the present invention is much easier and less expensive than with traditional flashing. Should a crack or hole form in the flashing of the present invention, it is relatively straight forward to apply a heat weld patch directly to the affected area. Such a repair will provide a consistent surface and will be long-lasting.
While this invention has been described in specific terms related to an exemplary embodiment or embodiments, it will be understood by those of skill in the art that modifications may be made in the configurations and dimensions of those embodiment(s) without departing from the following claims.