Venturi Ridge Vent

Abstract

A venturi ridge vent has an air-permeable vent body configured for mounting at the ridge of a pitched roof. The vent body defines a first opening and an opposing second opening and defines a flow path for air moving between the first and second openings. The first and second openings are disposed on opposing sides of the ridge when the vent body is mounted to the roof. The flow path defines a throat intermediate to the first and second openings. The throat area is less than the first or second opening areas to define a venturi. The attic is in fluid communication with the flow path proximal to the throat when the vent body is mounted to the roof.

I Claim: 
     
         1 . A venturi ridge vent for mounting on a pitched roof, the pitched roof having a ridge and an attic opening communicating through said pitched roof proximal to said ridge, the venturi ridge vent comprising:
 a. a vent body, said vent body being air-permeable, said vent body being configured to be mounted to the pitched roof at the ridge, said vent body having a configuration to support a shingle above said roof when said vent body is mounted to the roof at the ridge;   b. said vent body defining a vent first side and an opposing vent second side, said vent body being configured so that said vent first side is disposed on a ridge first side and said vent second side is disposed on an opposing ridge second side when said vent body is mounted to the pitched roof at the ridge;   c. said vent first side defining a first opening, said vent second side defining an opposing second opening, said first and said second openings being in fluid communication with one another and with the attic opening when said vent body is mounted to the roof at the ridge, said vent body defining a flow path for an air between said first opening and said second opening;   d. said first opening defining a first opening height and said second opening defining a second opening height, said flow path defining a throat proximal to said attic opening when said vent body is mounted to the roof at the ridge, said throat having a throat height, said throat height being less than said first opening height and said second opening height.   
     
     
         2 . The venturi ridge vent of  claim 1  wherein said vent body has a length, said length and said first opening height defining a first opening area, said length and said second opening height defining a second opening area, said length and said throat height defining a throat area, said throat area being less than said first opening area and said second opening area. 
     
     
         3 . The venturi ridge vent of  claim 2  wherein when said vent body is mounted to the roof at the ridge said air may pass along said flow path from a one of said first and second openings to another of said first and second openings, said air having a velocity, said velocity being greater at said throat than at said first opening and said second opening whereby said vent body defines a venturi. 
     
     
         4 . The venturi ridge vent of  claim 1  wherein said body is elongated, said body having a longitudinal axis, said longitudinal axis being parallel to the ridge when said body is mounted to the roof at the ridge and wherein said configuration of said vent body to support said shingle comprising: a shingle support, said shingle support being supported by said vent body, said shingle support being configured to receive a nail to secure said shingle support and said vent body to said roof, said shingle support in combination with the roof defines said first opening height, said second opening height and said throat height when said vent body is mounted to the roof at the ridge. 
     
     
         5 . The venturi ridge vent of  claim 1  wherein said vent body is elongated and defines a longitudinal axis, said vent body having a vent body height at each location between said first opening and said second opening, said vent body height narrowing in a tapered manner along said flow path between said first opening and said throat in a direction transverse to the ridge when said vent body is mounted to the roof at the ridge with said longitudinal axis parallel to the ridge, said vent body height increasing in a tapered manner along said flow path between said throat and said second opening in said direction transverse to the ridge when said vent body is mounted to the roof at the ridge with said longitudinal axis parallel to the ridge. 
     
     
         6 . The venturi ridge vent of  claim 5  wherein said configuration of said vent body to support said shingle comprises:
 a. a barrier of reduced permeability, said barrier of reduced permeability being disposed between said vent body and said shingle when said vent body is mounted to the roof at the ridge, said barrier of reduced permeability and said vent body in combination defining said flow path; and 
 b. a shim, said shim being disposed between said barrier of reduced permeability and said shingle when said vent body is mounted to the roof at the ridge, said shim in combination with said vent body and said barrier of reduced permeability defining a vent thickness, said vent thickness being substantially equal for each location on said vent body that is in contact with the roof when said vent body is mounted to the roof at the ridge, whereby a shingle supported by said shim is generally parallel to the roof when said vent body is mounted to the roof at the ridge. 
 
     
     
         7 . The venturi ridge vent of  claim 6  wherein said shim and said barrier of reduced permeability are one and the same. 
     
     
         8 . The venturi ridge vent of  claim 6 , said configuration of said vent body to support a shingle comprising: a shingle support, said shingle support being disposed between said shim and said shingle when said vent body is mounted on the roof at the ridge and said shingle is supported by said vent body. 
     
     
         9 . A method of ventilating a pitched roof, the pitched roof having a ridge and an attic opening communicating through said pitched roof proximal to said ridge, the method comprising:
 a. attaching a vent body to the roof at the ridge, said vent body being air-permeable, said vent body defining a first and an opposing second opening disposed on opposing sides of the ridge, said first and said second openings being in fluid communication with one another and with the attic opening, said vent body defining a flow path for an air between said first and said second openings, said flow path defining a throat intermediate to said first and second openings and proximal to said attic opening, said first opening defining a first opening height, said second opening defining a second opening height, said throat having a throat height, said throat height being less than said first opening height and said second opening height;   b. supporting a shingle by said vent body.   
     
     
         10 . The method of  claim 9  wherein said step of attaching said vent body to the ridge further comprises: providing that said first opening defines a first opening area, said second opening defines a second opening area and said throat defines a throat area, said throat area being less than said first or second opening area. 
     
     
         11 . The method of  claim 10  wherein an air may pass along said flow path through said vent body from a one of said first and second openings to another of said first and second openings in response to a wind transverse to the ridge, said air having a velocity, said velocity being greater at said throat than at said first opening and said second opening whereby said vent body defines a venturi. 
     
     
         12 . The method of  claim 10  wherein said step of attaching said vent body to the ridge further comprises: providing that said vent body is elongated and defines a longitudinal axis, said longitudinal axis being disposed parallel to the ridge of the roof, said vent body defining a shingle support, said shingle support being supported by said vent body, said shingle support receiving a nail securing said shingle, said shingle support and said vent body to said roof, said shingle support in combination with said roof defining said first opening height, said second opening height and said throat height. 
     
     
         13 . The method of  claim 10  wherein said step of attaching said vent body to the ridge further comprises: providing that said vent body defines a flow path height at each location between said first opening and said throat and between said throat and said second opening, said flow path height narrowing in a tapered manner between said first opening and said throat in a direction transverse to the ridge, said flow path height increasing in a tapered manner between said throat and said second opening in said direction transverse to the ridge. 
     
     
         14 . The method of  claim 10  wherein said step of attaching said vent body to the ridge further comprises:
 a. providing a barrier of reduced permeability disposed between said vent body and said shingle, said barrier of reduced permeability and said vent body in combination defining said flow path; and 
 b. providing a shim, said shim being disposed between said barrier of reduced permeability and said shingle, said shim in combination with said vent body and said barrier of reduced permeability defining a vent thickness, said vent thickness being substantially equal for each location of said vent body that is in contact with the roof, whereby said shingle is parallel to the roof. 
 
     
     
         15 . The method of  claim 14  wherein said shim and said barrier of reduced permeability are one and the same. 
     
     
         16 . The method of  claim 10  wherein said step of attaching said vent body to the ridge further comprises: providing a shingle support, said shingle support being supported by said vent body, said shingle support receiving a nail to secure the shingle, said shingle support, and said vent body to the roof, said shingle support in combination with the roof defines said first opening height, said second opening height and said throat height.