Abstract:
A self-adhering ice and water roofing membrane, having a roofing underlayment attached to it, wherein the roofing underlayment also serves as the carrier for the release layer, and is needed to transport the self adhering roofing membrane from the manufacturer to the construction site. A splitable adhesive may be used in place of the release layer on the underlayment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    None 
       FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable. 
       TECHNICAL FIELD 
       [0003]    The present invention relates to a roofing underlayment product, and more particularly to a roofing underlayment product for use in weatherproofing a roof deck structure, including against ice and water damage, wherein a roofing underlayment sheet is factory sealed with, or integrally formed to, a weatherproof membrane creating a unified product. 
       BACKGROUND OF THE INVENTION 
       [0004]    In both residential and commercial roofing applications, a roof covering material is utilized as the main water protection barrier between the roof deck structure and the outer roof surface, which may include shingles, metal panels of shingles, concrete or clay tiles, wood shakes or slate. In addition to the standard roofing underlayment or “felt,” an ice and water barrier membrane is particularly useful and necessary in those regions subject to ice dam formation or wind-driven rain. Ice dams form when the water from melting snow runs down the warmer roof and freezes at the generally colder eave. Water becomes trapped behind the ice dam and eventually backs up under the shingles and the nails securing the shingles to the roof deck, leaking through and causing damage to the roof deck and interior of the structure. In other situations, wind-driven rains may lift the shingles, permitting water to enter under the shingles to the roof deck and ultimately to the interior of the structure. Ice and water barrier membranes are typically applied near the edge or eaves of the roof, as that is the area most prone to the formation of ice dams and lifting of the shingles by wind. Standard ice and water barrier membranes include those offered under the name ICE &amp; WATER SHIELD® from W.R. Grace &amp; Co. 
         [0005]    The roofing underlayment or felt and ice and water barrier membranes are applied either mechanically, by nailing, or by adhesives, also known as “peel and stick.” Because the “peel and stick” ice and water barrier membrane incorporates a release liner covering the adhesive until the product is ready for installation, it is believed that approximately 15,000 tons of release liner is currently being used in the industry. The release liner is discarded as waste after application of the ice and water barrier membrane. Switching to a “liner-less” product in at least 70-85% of all applications could reduce the waste by as much as 10,000 tons per year. A liner-less product would also reduced the overall applied cost of the roof membrane and underlayment. 
         [0006]    After the ice and water barrier membrane is attached, the roofer then installs the first roofing underlayment layer. The two materials are overlapped, typically by about 4 inches to create a seal between them. This seal is the most important seal, since in extreme cases, water could back up to a higher level of the roof. If the seal between the ice and water barrier and the underlayment sheet is not formed correctly, the ice and water shield could fail. Providing a factory made “first” seal between the self adhering ice and water barrier membrane and the underlayment sheet would provide a more reliable product. 
         [0007]    The present invention seeks to overcome certain limitations and other drawbacks of the prior art, and to provide new features not heretofore available. Some of the features provided by the present invention include the following: providing a liner-less product, thus reducing waste and overall applied cost associated with the throw away standard release liner; providing a “factory-made” seal between the ice and water barrier membrane and the roofing underlayment layer, ensuring a more weatherproof product; and reducing installation time and providing a cost savings due to the one-step installation of the combined underlayment and ice and water barrier product. Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention relates to a self-adhering roofing underlayment product for positioning between a roof support deck and a roof outer structure, such as shingles, to provide a waterproof barrier. The product does not require the use of a release liner. The underlayment product comprises a self-adhering, multi-layered ice and waterproof barrier membrane, including a first outer layer, a second layer of protection material and a third self-adhering adhesive layer. A roof underlayment sheet is attached to and forms a seal with one of either the first layer or the second layer of the barrier membrane. A release layer is applied directly to the roofing underlayment sheet. 
         [0009]    Another embodiment of the present invention relates to a one-piece roofing underlayment product including a combined ice and water barrier membrane and a roofing underlayment sheet layer. The ice and water barrier membrane includes a first membrane outer layer, a second layer of weatherproofing material, and a third adhesive layer. The product includes a roofing underlayment layer having a first end and a second end. A release layer is applied to the roofing underlayment layer; wherein the first end of the roofing underlayment layer replaces a portion of the first membrane outer layer and is sealed directly on top of the second weatherproofing layer. The second end of the underlayment layer has a width at least twice that of the barrier membrane, the second end being doubled over onto itself to permit removal of the underlayment layer away from the release layer for installation of the sheet. 
         [0010]    In another embodiment of the present invention, the release layer is replaced by a splittable adhesive. 
         [0011]    A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    To understand the present invention, it will now be described by way of example, with reference to the accompanying drawings in which: 
           [0013]      FIG. 1  is a perspective view of the prior art. 
           [0014]      FIG. 2  is a perspective view of a first embodiment of the present invention. 
           [0015]      FIG. 3  is a perspective view of a second embodiment of the present invention. 
           [0016]      FIG. 4  is a perspective view of a third embodiment of the present invention. 
           [0017]      FIG. 5  is a perspective view of a fourth embodiment of the present invention. 
           [0018]      FIG. 6  a perspective view of a fifth embodiment of the present invention. 
           [0019]      FIG. 7  a perspective view of a sixth embodiment of the present invention. 
           [0020]      FIG. 8  is a perspective view of a seventh embodiment of the present invention. 
           [0021]      FIG. 9  is a perspective view of a eighth embodiment of the present invention. 
           [0022]      FIG. 10  is a perspective view of a ninth embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. 
         [0024]    Referring now to the figures,  FIG. 2  illustrates a first embodiment of a weatherproof roofing underlayment product  10  for positioning between a roof support and a roof structure to provide a uniform waterproof barrier. The underlayment product  10  comprises a self-adhering ice and water roof barrier membrane  12 , having a first outer layer  14 , a second layer of protection material  16  and a third self-adhering adhesive layer  18 . A roofing underlayment sheet  20  replaces the standard release liner Z 3  on the ice and water barrier material Z 1  of the prior art ( FIG. 1 ). A release layer  22 , typically of a silicone material, is positioned on the underlayment sheet  20 . 
         [0025]    As may best be seen in  FIG. 3 , in a preferred embodiment of the present invention, the underlayment sheet  20  is attached to and forms a seal  24  with either the first layer  14  or the second layer  16  (not shown). Optionally, as will be described later, a splittable adhesive could be used instead of the combination of a release liner and an adhesive ( FIG. 8 ). 
         [0026]    The ice and water barrier membrane  12  is a standard product for use in the roofing industry to provide protection against the formation of ice dams, wind-driven rain, and the resulting water damage to roof structures, as well as to the interior of the structure and items contained therein, caused by these factors. These barrier membranes are readily available to the consumer or trade. Typical ice and water barrier products useful in the present invention include those available from W.R. Grace &amp; Co., under the trademark ICE &amp; WATER SHIELD® (see, for example, U.S. Pat. No. 5,687,517) and Owens Corning under the trademark WEATHERLOCK®. The ice and water barrier membrane is typically applied adjacent to the lower edge of the eave of the roof deck. 
         [0027]    As shown in  FIG. 2 , typical ice and water barrier membranes  12  useful in the present invention include a first outer layer  14 , a second layer of protection material  16 , and a third self-adhering adhesive layer  18 . Standard, prior art weatherproofing barrier membranes also include a release liner, typically a polypropylene film or a poly coated paper, which protects the adhesive layer, and is removable on application of the barrier membrane. The first outer layer  14  may be a polyolefin film, a non-woven or fibrous surface, a mineral sanded surface, or a combination of all of these, which could be a mono-layered or a multi-layered structure. Ice and water membranes are generally applied toward the roof eave, where ice dams commonly form. These ice and water membranes have typical dimensions of 20 to 48 inches wide and 40 to 200 mil thickness. 
         [0028]    As may best be seen in  FIG. 2 , the ice and water barrier membrane  12  includes a second layer  16  of waterproofing protection material, typically a bituminous material. Bituminous materials are well-known, and include compositions containing asphalt, or tar, such as coal tar or pitch. Bituminous materials may also include fibers or particulate fillers, such as poly fibers, glass fiber, or mineral fillers, e.g., sand or calcium carbonate. 
         [0029]    The ice and water barrier membrane  12  also includes a self-adhesive layer  18 . Typically, the adhesive is a pressure-sensitive adhesive. Non-limiting examples of such a pressure-sensitive adhesive include plasticized SBR rubber, plasticized hydrocarbon resins, plasticized neoprene rubber, and polybutyl resin. The combination of the release liner  20  and the adhesive layer  18  give the barrier membrane  12  its “peel and stick” characteristic. 
         [0030]    Prior art ice and water barrier membranes include a release liner Z 3  ( FIG. 1 ). The release liner Z 3  of the prior art, typically a paper, a polyolefin-coated paper, or polyolefin film material, contacts and protects the adhesive layer Z 2  until the ice and water barrier membrane Z 1  is attached to the roof support structure. At that time, the release liner Z 3  is removed and discarded, exposing the adhesive so that the ice and water barrier membrane can be attached to the roof support. 
         [0031]    In a preferred embodiment of the present invention, the standard release liner is replaced by a roofing underlayment layer  20 . The roofing underlayment layer  20  or “felt” is typically used as a weather-resistant membrane and applied to the roof support structure or deck, above the ice and water barrier  12 , which is typically applied adjacent the eaves. It is standard in the industry to apply the roofing underlayment layer  20  separate from the ice and water barrier membrane  12 . The roofer must overlap the two products and provide a seal between the ice and water barrier  12  and the roofing underlayment layer  20 . If this seal is not properly constructed by the on-site roofer, a failure of the ice and water barrier can result, causing water damage to the roof deck, and potentially to the interior of the structure. The preferred embodiment of the present invention eliminates this two-step application of the weatherproofing materials, and provides a factory-made, weatherproof seal between the roofing underlayment layer and the ice and water barrier membrane. 
         [0032]    As may be seen in  FIGS. 2-3 , the roofing underlayment layer  20  includes a silicone release layer  22 , therefore forming a siliconized roofing underlayment. The release layer is preferably a crosslinked polydimethyl siloxane layer, but may also include a non-crosslinked polydimethyl siloxane or extrudable release material, e.g., a long chain silicone polymer or polyolefin/silicon co-polymer or a non-silicone-based release material, which could be starch ester or melamin-based. The combination of the roofing underlayment layer  20  with the release layer  22  replaces the traditional release liner  21  used in connection with the ice and water barrier membrane  12  described above. Various embodiments of the present invention will now be described, with reference to  FIGS. 3-10 . 
         [0033]    As shown in  FIG. 3 , in a second embodiment of the present invention, the siliconized roofing underlayment layer  20  has a factory seal  24  to a top layer  14  on the ice and water barrier membrane  12 . In order to apply the product  10 , which comes in a rolled form, the roofer would reach under the product roll, and grasp one end of the roofing underlayment layer  20 , pulling it away from the edge of the roof for application. This permits one-stage installation of both the roofing underlayment layer  20  and the ice and water barrier membrane layer  12 . 
         [0034]      FIG. 4  illustrates a third embodiment of the present invention. While this embodiment also includes the factory seal  24  of the roofing underlayment  20  to the ice and water barrier membrane  12 , it also includes use of a release liner  21 , although at a significantly reduced size from that generally used in connection with typical ice and water barrier membranes. In this embodiment, as well as the embodiment of  FIG. 2 , an end  20   a  of the siliconized roofing underlayment layer overlaps with the release liner  21  ( FIG. 4 ), or optionally, joins as a serrated edge with the release liner. When the product  10  is applied to the roof, the release liner  21  is placed nearer the roof edge. Removal of the release liner  21  provides a starting point for the roofer to unroll the roofing underlayment  20  away from the ice and water barrier membrane when installing the product. In contrast to the above embodiment, the roofer is not required to reach under the product to the same extent as in the above embodiment of  FIG. 3 , leading to an improved ease of installment of this embodiment. 
         [0035]      FIG. 5  illustrates a fourth embodiment of the present invention. While this preferred embodiment also includes the factory seal  24  between the roofing underlayment  20  and the ice and water barrier membrane  12 , the roofing underlayment has a width of at least twice that of the roofing membrane. With this feature, an edge piece  20   b  of the roofing underlayment  20  permits the roofer to easily and more efficiently grab onto and pull the edge  20   b  of the underlayment layer out from underneath the product, and up the roof. In addition, because the underlayment layer  20  is now double in size, there is a time savings in terms of installation because a larger area of the roof deck can be covered at one time. 
         [0036]      FIG. 6  illustrates a fifth embodiment of the present invention. In this particular embodiment, which includes the factory seal  24 , the underlayment layer  20  is similar to that in the embodiment of  FIG. 5 . However, this embodiment also includes a standard release liner  21 , which positions the underlayment layer closer to the end of the roll, making it easier for the roofer to pull the end of the underlayment layer out from under the product. In this embodiment, the underlayment layer  20  is about half the length as that of the embodiment in  FIG. 5 , with the addition of the release liner  21 , making it easier to pull the underlayment  20  layer out from under the product, providing for easier installation. 
         [0037]      FIG. 7  illustrates a sixth embodiment of the present invention. This particular embodiment is similar to that shown in  FIG. 5 , wherein the roofing underlayment layer  20  is at least twice as long as previous embodiments. The distinction, however, is in the factory seal  26  between the roofing underlayment  20  and the ice and water barrier membrane  12 . In this embodiment, the first outer layer  14  of the ice and water barrier  12  is actually integrated with, or optionally, replaced by, a portion of the underlayment layer. Typically, there is a standard  4  inch overlap for the factory seal amounting to 10% of the outer layer  14  if the membrane is 40 inches wide. 
         [0038]      FIG. 8  represents another preferred embodiment of the present invention, with the same features as the product in  FIG. 7 , with the exception that the release layer is replaced by a splittable adhesive  28 . As with the earlier embodiment, the first outer layer  14  of the ice and water barrier  12  is actually integrated with, or optionally, a substantial portion of the first outer layer is replaced by the underlayment layer  20  forming a seal  26 . The splittable adhesive  28  acts like the release layer  22 , in that it splits into layers, such that the majority of the adhesive remains on the ice and water barrier membrane  12  to secure the barrier membrane to the roof deck. The remainder of the adhesive  28  stays with approximately half of the underlayment layer  20 , which can now be secured to the roof deck using the adhesive and optionally, further secured with nails. Adhesives suitable for the present invention include, for example, a hot melt adhesive useful in pressure sensitive applications, similar to Eukalin 599 VDC offered by Eukalin in Germany. 
         [0039]      FIG. 9  represent a tenth embodiment of the present invention. This embodiment includes the features shown above in  FIG. 7 , specifically concerning integration or replacement of a suitable portion of the outer layer  14  of the barrier membrane  12  with the underlayment layer  20 , and the double length of the underlayment layer. However, this embodiment further includes the addition of a starter strip  30 , which permits the roofer to attach the ice and water barrier membrane  12  to the edge of the roof, prior to pulling out the underlayment layer  20 . The starter strip may be a siliconized polyolefin film or some other standard paper-based release liner, which is removed to expose an adhesive layer. Optionally, the starter strip may be a selvage edge  32 , which does not include an adhesive layer ( FIG. 10 ). In this option, the selvage edge  32  is secured to the edge of the roof by standard gluing or nailing. In yet another option of this embodiment, using either the starter strip  30  or the selvage edge  32 , the release layer  22  of this embodiment may be replaced by the splittable adhesive layer  28  discussed in the embodiment of  FIG. 8 . 
         [0040]    Several alternative embodiments and examples have been described and illustrated herein. A person of ordinary skill in the art would appreciate the features of the individual embodiments, and the possible combinations and variations of the components. A person of ordinary skill in the art would further appreciate that any of the embodiments could be provided in any combination with the other embodiments disclosed herein. Additionally, the terms “first,” “second,” “third,” and “fourth” as used herein are intended for illustrative purposes only and do not limit the embodiments in any way. Further, the term “plurality” as used herein indicates any number greater than one, either disjunctively or conjunctively, as necessary, up to an infinite number. 
         [0041]    It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein. Accordingly, while the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention and the scope of protection is only limited by the scope of the accompanying Claims.