Patent Application
20230010965
This invention relates to a multi-layered engineered roofing structural panel (which can be wood-based, such as, but not limited to, oriented-strand board (OSB), plywood, or other lignocellulosic-based panel) with integrated ventilation.
Current roof assemblies are typically multiple layers of several materials, each performing a single function, that are installed separately on the site in which the building is being constructed. In many roofing systems, there is a deck, an underlayment barrier on top of the deck, covered by a surface layer of shingles (e.g., asphalt, ceramic, metal, and the like). Compatibility between the various layers creates challenges not only for the designer, but also for the installers. In addition, a varied and large amount of materials are required during the installation, as well as during maintenance (e.g., re-roofing).
A central layer in most such assembles in a wood panel product, or an integral composite engineered panel product, including, but not limited to, engineered wood composite products formed of lignocellulosic strands or wafers (sometimes referred to as oriented-strand board, or OSB). Products such as fiberboard and particleboard have been found to be acceptable alternatives in most cases to natural wood paneling, sheathing and decking lumber. Fiberboard and particleboard are produced from wood particles bonded together by an adhesive, the adhesive being selected according to the intended use of and the properties desired for the lumber. Often times, the adhesive is combined with other additives to impart additional properties to the lumber. Additives can include, but are not limited to, fire retardants, insect repellants, moisture resistant substances, fungicides and fungal resistant substances, and color dyes. A significant advantage of fiberboard and particleboard lumber products is that they have many of the properties of plywood, but can be made from lower grade wood species and waste from other wood product production, and can be formed into lumber in lengths and widths independent of size of the harvested timber.
A major reason for increased presence in the marketplace of the above-described product alternatives to natural solid wood lumber is that these materials exhibit properties like those of the equivalent natural solid wood lumber, especially, the properties of retaining strength, durability, stability and finish under exposure to expected environmental and use conditions. A class of alternative products are multilayer oriented wood strand particleboards, particularly those with a layer-to-layer oriented strand pattern, such as OSB. Oriented, multilayer wood strand boards are composed of several layers of thin wood strands, which are wood particles having a length which is several times greater than their width. These strands are formed by slicing larger wood pieces so that the fiber elements in the strands are substantially parallel to the strand length. The strands in each layer are positioned relative to each other with their length in substantial parallel orientation and extending in a direction approaching a line which is parallel to one edge of the layer. The layers are positioned relative to each other with the oriented strands of adjacent layers perpendicular, forming a layer-to-layer cross-oriented strand pattern. Oriented, multilayer wood strand boards of the above-described type, and examples of processes for pressing and production thereof, are described in detail in U.S. Pat. Nos. 3,164,511, 4,364,984, 5,435,976, 5,470,631, 5,525,394, 5,718,786, and 6,461,743, all of which are incorporated herein in their entireties by specific reference for all purposes.
In various exemplary embodiments, the present invention comprises a multi-layer panel for use as integrated structural sheathing on a roof, with integrated drip edge or “driplap edge.” The integrated roofing panel comprises a multi-layer panel or plank 2 for use as integrated structural sheathing on a roof. The lower (or “downhill”) edge of certain integrated roofing panels, such as those that are “starting planks” 4 (as described more fully below) comprises an integrated “driplap edge” 6 that promotes water evacuation from the roof surface while keeping it away from the walls below the roof edge.
In various exemplary embodiments, as seen in
The multi-layer integrated roofing product comprises a wood structural panel or plank 10. The wood may be natural or manufactured, engineered wood, such as oriented strand board (OSB) or plywood. The panel may be coated or treated, during or after the manufacturing process, with a product that provides various properties, such as, but not limited to, weather resistance, fungus resistance, insect resistance, and/or fire resistance. The treatment may be integrated with the material forming the wood structural panel, or may be a coating on one or both surfaces. Examples of integrated roofing panels are disclosed in U.S. patent application Ser. No. 17/068,712, filed Oct. 12, 2020 by Louisiana-Pacific Corp, and U.S. patent application Ser. No. 17/200,648, filed Mar. 12, 2021, both of which are incorporated herein in their entireties by specific reference for all purposes.
Prior art drip edges for roofing installations typically are made of aluminum and installed over the sheathing and covered with shingles or metal roofing. This is not possible with the integrated roofing panels as described herein, due the integration of the surface layer in the panel during the manufacturing process. Accordingly, an angle 6a is machined or milled along the horizontal bottom edge of the starting plank 4 (i.e., the piece used at the beginning of the roof assembly). This process may be performed at a factory as part of the manufacturing process. In several embodiments, the angle 6a between the face of the edge and the upper surface 6a of the starting plank 4 is acute. In some embodiments, the angle is 25 degrees or approximately 25 degrees. In alternative embodiments, the angle is approximately 25 degrees, +/−2 degrees, or approximately 23 to 27 degrees. This angle allows for water to be evacuated from the roof away from the house at any roof pitch (as well as reducing installation steps, as the installation of separate drip edges at the job site is eliminated, thereby allowing a reduction in time and cost of installation). This machined angle allows for water evacuation from the roof surface while keeping it away from the walls. It also does not allow water to migrate under the roof, thereby effectively avoiding any potential leak/water damage to the adjacent structural elements in contact with the starting plank.
In several embodiments, a weather or water resistive barrier (WRB) 20 of some kind is applied to the upper or outward facing surface of the panel 10, effectively serving as an underlayment. The WRB may be a form of paper overlay, a form of spray-applied or fluid-applied polymer or material (such as silicone), or other form of WRB. In some embodiments, the WRB may include a granular or solid material 40 as a texturizing aggregate or material (such as, but not limited to, ceramic coated granules, clay, rock, glass, slate, styrene, particles of polymeric plastic, or combinations thereof) as a component or part of the WRB itself (e.g., texturizing aggregate or material may be mixed with a liquid polymer WRB). Alternatively, the granular or solid material 40 may be subsequently applied directly to the WRB after the WRB is applied to the plank/panel. In yet a further embodiment, the outer surface of the WRB may be coated with a polymer, adhesive and/or asphalt 30, which is turn is coated with the granular or solid material 40. In some embodiments, the adhesive and/or asphalt may include the granular or solid material as a component or part (e.g., texturizing aggregate or material may be mixed with the adhesive and/or asphalt). In alternative embodiments, an outer polymeric layer also may act as an aesthetics or appearance layer, in which case addition granular or solid material may or may not be present.
The invention thus effectively combines a structural sheathing panel, WRB layer or polymer, and texturizing aggregates or materials, if present (e.g., surface layer, shingles, metals, or other roof surface materials), as separately applied in the prior art, into one multi-layer panel product, which is less reliant on skilled labor for installation at a job site and reduces installation time by eliminating the separate sequential application of a WRB system and a surface layer in the installation process. As discussed above, in some embodiments, the WRB may be a separate layer, or it may be integrated with the texturizing aggregate/surface layer.
In several embodiments, the texturizing aggregate or top surface layer may be one or more flexible rolls of material, which may be applied by unrolling the material across the panel during manufacture (or, in some embodiments, at the job site). The roll may have a self-adhesive layer on one side. In one embodiment, the surface layer rolls may comprise one or more rolls of one-sided or two-sided construction tape (i.e., with strong, permanent adhesive on one or two sides). One side of the tape adheres to the panel, while the other side contains the surface material. The tape may be applied to the panel at the factory, or otherwise prior to installation at the job site.
Some or all of the respective faces of the shiplap joint may be covered with the WRB polymer layer 22.
An integrated sealant or adhesive material, such as the WRB polymer 22 or other form of sealant or adhesive, is applied to one face (or both faces) of corresponding overlap and/or underlap sections. Where the WRB polymer is used as a sealant, the two surfaces coated with the polymer are placed in contact with each other. Nails or similar fasteners used to affix the planks/panels to the roofing structure may be used in the joint area to keep the surfaces in contact (and apply a level of pressure thereto) to cause the polymer-covered surfaces to self-seal.
In an additional embodiment, as seen in
“Starter” roofing pieces 110 are shown in
During installation, a course or row of “starter” roofing pieces 110 is affixed along the bottom edge of the roofing, with the underlap section on the top edge. A course of standard roofing pieces 100 is then applied, with the overlap section on the bottom edge overlaying the underlap section of the lower course to form a shiplap joint that is airtight and watertight. A number of standard roofing piece courses are then added in sequence up the roof to near the top, with the number determined by the size (height) of the roof. A course or row of “crown” roofing pieces 120 is then added as the final topmost course, with the overlap section on the bottom edge overlaying the underlap section of the lower course, as described above.
The right and/or left ends of the plank/panel may be sealed with the WRB or a sealant. As discussed above, one form of sealant may be double-sided tape 28. Alternatively, an “end cap” may be applied to cover the ends.
In several embodiments, as seen in
The present invention applies the WRB and texturizing aggregate (either integrated or as separate layers) to the plank/panel at a manufacturing facility, prior to shipping or installation at a job site (and thereby avoiding the problems noted above with regard to prior art installations). In one embodiment, a fluid or liquid applied membrane is applied via one or more spray nozzles in a manufactured line process. The spray nozzle or nozzles are in fluid communication with one or more storage tanks, and the membrane liquid may be stored without the use of agitators. Nozzles apply the membrane coating at a constant pressure until reaching the desired wet film thickness. As the plank/panel travels down a secondary production line (typically on a form of conveyor belt), the WRB coating is sprayed on the top face, and in some embodiments, also the edges, of the plank/panel at a minimum thickness of 5-10 mils. If the coating is not sprayed on the edges, the edges are sealed by other means. The asphalt/adhesive and/or surface layers, if separate from each other and from the WRB layer, may be applied in a similar manner. In other embodiments, the WRB may be a solid layer (e.g., paper overlay), as seen in
In some embodiments, the present invention is produced through a curtain coating method. A storage tank containing the membrane liquid is positioned above the secondary production line. The tank has a longitudinal aperture that allows the membrane liquid to flow from the tank onto the plank/panel as it passes beneath the tank. The width of the aperture is adjusted so the amount of liquid flowing onto the plank/panel is the correct amount to achieve the desired wet film thickness of the coating. In other embodiments, In some embodiments, the present invention is produced through a roll coating method. Two or more rolls (e.g., a doctor roll and a coating roller) are positioned above the secondary production line. The membrane liquid (e.g., the polymer coating) is located between the rolls, and passes between the rolls and is applied to the surface of the plank/panel traveling on the line by the coating roller. The position of the doctor roll relative to the coating roller is adjusted to let pass the correct amount of liquid pass to achieve the desired wet film thickness of the coating.
In several embodiments, the texturizing surface and/or shingle layer may be one or more flexible rolls of material, and applied by unrolling the material across the plank/panel. The roll may have a self-adhesive layer on one side. In one embodiment, the shingle layer rolls may comprise one or more rolls of one-sided or two-sided construction tape (i.e., with strong, permanent adhesive on one or two sides). One side of the tape adheres to the panel, while the other side contains the shingle material. The tape may be applied to the panel at the factory, or otherwise prior to installation at the job site.
In the embodiments seen in
“Starter” pieces with flashing 314, 316 are shown in
In a further embodiment, a radiant barrier layer 50 may be applied to the underside of the panel. Radiant barrier sheathing, typically used for roof and attic sheathing, has become a de facto standard in high solar radiation environments. Radiant barriers are installed in homes and structures, usually in attics, primarily to reduce summer heat gain and reduce cooling costs. The barriers consist of a highly reflective material that reflects radiant heat rather than absorbing it. Radiant heat travels in a straight line away from any surface and heats anything solid that absorbs its energy. Most common insulation materials address conductive and convective heat flow, not radiant heat flow. In contrast, a radiant barrier reduces the radiant heat transfer from the underside of the heated roofing materials to other surfaces in the attic, thereby reducing the cooling load of the house.
A layer of aluminum (typically aluminum foil) is commonly used as the reflective material, as it is efficient at not transmitting radiant energy into the attic environment. The aluminum foil used in radiant barriers must be very pure to achieve a low emittance surface. The thickness of the aluminum does not affect performance; the aluminum only needs to cover the surface of the sheathing material. Typically, very thin foils (approximately 0.00025 inches thick) are used. As this foil is too thin (and thus too fragile) to be applied to wood structural panels directly, it may be attached and bonded to another substrate, most often Kraft paper, for support. The combined overlay is then laminated to one side of a wood structural panel face to make the radiant barrier sheathing. As an alternative to foil, a very thin layer of aluminum (or similar metal) can be deposited via vapor deposition manufacturing processes onto a polyethylene sheet (PET) to form a metallized PET sheet. Like foil, the metallized PET sheet can be laminated to Kraft paper, and the combined overlay is laminated to one side of a wood structural panel face to make the radiant barrier sheathing.
In several additional embodiments, end pieces 400 of the present system (i.e., the integrated panels that are installed at or adjacent to the roof of the ridge) comprise vents 410 or other ventilation means installed or integrated with the panel at the factory (i.e., during the manufacturing process). In the embodiment shown, the vents are formed by rectangular sections of longitudinal cuts made along the panel or plank. The cuts may be similar to a vented soffit, but the surface of the cut area is coated with a water-resistant finish. The vents may be located along the upper part of the plank (i.e., proximate the ridge of the roof), which permits coverage by felt fabric and ridge cap.
Installation of the end piece may be done to match the edge of the ridge. The integrated ventilation system saves time and labor, as it allows installers to simply place the end piece by the ridge without leaving gaps (which would need to be measured) or being sawn. The factory-installed vents also create a more controlled and energy efficient roof ventilation system.
The present invention possesses several advantages over the prior art. It provides a superior barrier system that does not allow air movement between the panel face and the applied WRB, and allows a savings in time and labor. Further, coating the panels in a controlled setting (e.g., manufacturing facility), allows the thickness of the coatings to be consistently applied, and allows the coating the opportunity to fully bond with the panel or adjacent layer. More specifically, the coatings can fully cure independent of weather conditions, and be applied without interference from construction-related dirt, debris or humidity. Further, the mineral granules or other texture-providing material may be included to increase the aesthetic appeal of the product, as well as to serve as a cooling agent in some cases, thereby enhancing energy efficiency.
Thus, it should be understood that the embodiments and examples described herein have been chosen and described in order to best illustrate the principles of the invention and its practical applications to thereby enable one of ordinary skill in the art to best utilize the invention in various embodiments and with various modifications as are suited for particular uses contemplated. Even though specific embodiments of this invention have been described, they are not to be taken as exhaustive. There are several variations that will be apparent to those skilled in the art.
This application claims benefit of and priority to U.S. Provisional App. No. 63/218,587, filed Jul. 6, 2021, and is incorporated herein in its entirety by specific reference for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| 63218587 | Jul 2021 | US |
