Roofing underlayment with nail sealing system

Abstract

A sheet of roofing underlayment comprises a base layer, a water-impermeable coating layer laminated to one side of the base layer, and a plurality of spaced-apart sealant areas between the coating layer and the base layer, comprising a sealant adapted to form a seal around a fastener penetrating the sheet. The sealant area may be continuous or intermittent strips. The sealant forms a water-tight seal around the fasteners used to attach the roofing underlayment to a roof deck.

1 . A sheet of roofing underlayment, comprising:
 (a) a base layer;   (b) a water-impermeable coating layer laminated to a first side of the base layer; and   (c) a plurality of spaced-apart sealant areas between the coating layer and the base layer, comprising a sealant adapted to form a seal around a fastener penetrating the sheet.   
     
     
         2 . A sheet according to  claim 1 , wherein the sealant is uncured and is adapted to cure upon exposure to air or humidity. 
     
     
         3 . A sheet according to  claim 1 , wherein the sealant is cured. 
     
     
         4 . A sheet according to  claim 1 , wherein the sealant is one of a hot melt adhesive, silicone, glue, modified bitumen and rubberized asphalt. 
     
     
         5 . A sheet according to  claim 1 , wherein the sealant areas are colored and visible through the coating. 
     
     
         6 . A sheet according  claim 1 , wherein the sealant areas comprise continuous or intermittent strips. 
     
     
         7 . A sheet according to  claim 6 , wherein the strips are located along two longitudinal edges of the sheet. 
     
     
         8 . A sheet according to  claim 7 , wherein at least one continuous or intermittent strip is located along a middle part of the sheet. 
     
     
         9 . A sheet according to  claim 1 , wherein the base layer is a scrim. 
     
     
         10 . A sheet according to  claim 1 , wherein the base layer is a non-woven. 
     
     
         11 . A sheet according to  claim 1 , wherein the base layer is a film. 
     
     
         12 . A sheet according to  claim 1 , wherein the base layer comprises one of a polyolefin, a polyester, polystyrene, nylon, and an ethylene acrylic copolymer. 
     
     
         13 . A sheet according to  claim 1 , wherein the coating layer comprises one of a polyolefin, a polyester, polystyrene, nylon, and an ethylene acrylic copolymer. 
     
     
         14 . A sheet according to  claim 1 , further comprising a second coating layer laminated to a second side of the base layer. 
     
     
         15 . A sheet according to  claim 1 , wherein the thickness of the base layer or the coating layer, or both, adjacent to the sealant areas is less than the thickness of the base layer or the coating layer, respectively, in non-adjacent areas. 
     
     
         16 . A sheet according to  claim 15 , wherein the sheet has a substantially uniform thickness. 
     
     
         17 . A sheet according to  claim 6 , wherein the strips osculate along a longitudinal direction of the sheet. 
     
     
         18 . A sheet according to  claim 1 , further comprising a second plurality of spaced-apart sealant areas laminated to the outside of the sheet and aligned with the sealant areas between the coating layer and the base layer. 
     
     
         19 . A sheet of roofing underlayment, comprising:
 (a) a base layer;   (b) a first water-impermeable coating layer laminated to a first side of the base layer;   (c) a second water-impermeable coating layer laminated to a second side of the base layer; and   (d) a first plurality of spaced-apart sealant areas between the coating layer and the base layer, comprising a sealant adapted to form a seal around a fastener penetrating the sheet.   
     
     
         20 . A sheet according to  claim 19 , further comprising a second plurality of spaced-apart sealant areas laminated to the outside of the first coating layer and aligned with the first plurality of sealant areas. 
     
     
         21 . A sheet according to  claim 19 , further comprising a third plurality of spaced-apart sealant areas laminated to the outside of the second coating layer and aligned with the first plurality of sealant areas.