Roof-mounted ventilation air duct

Abstract

A ventilation air duct is anchored to a flat roof of a building by means of a ballast material, such as gravel. The weight of the ballast material is selected to secure the duct to the roof without any other fasteners.

What is claimed is: 
     
         1 . A roof-mounted ventilation air duct adapted to be connected to a ventilation unit on a flat roof of a building comprising a plurality of duct sections adapted to be connected end to end in fluid flow communication to form a fluid passage for allowing air to flow therethrough, wherein at least some of said plurality of duct sections are provided with a ballast receiving portion, and a ballast material adapted to be disposed on said ballast receiving portion for anchoring the duct sections to the flat roof under the weight of the ballast material, the duct sections and the ballast material having a combined weight which is selected to render said duct sections immovable to side winds on the flat roof of the building. 
     
     
         2 . The roof-mounted ventilation air duct of  claim 1 , wherein at least a plurality of said duct sections further comprise a lid to provide access to the fluid passage and the ballast receiving portion, the ballast receiving portion being located within the duct sections. 
     
     
         3 . The roof-mounted ventilation air duct of  claim 1 , wherein said ballast material is a thermal mass which is in heat exchange relationship with the duct sections one placed on said ballast receiving portion. 
     
     
         4 . The roof-mounted ventilation air duct of  claim 3 , wherein said ballast material is dispensed in the fluid passage such as to be in direct contact with the air flowing therethrough. 
     
     
         5 . The roof-mounted ventilation air duct of  claim 1 , wherein at least some of said duct sections are provided on an equator-facing outside surface with a collector panel adapted to absorb incident solar radiation. 
     
     
         6 . The roof mounted ventilation air duct of  claim 5 , wherein the collector panel has a plurality of inlet air openings. 
     
     
         7 . The roof-mounted ventilation air duct of  claim 5 , wherein the collector panel comprises transparent material. 
     
     
         8 . The roof-mounted ventilation air duct of  claim 4 , wherein the collector panel is selectively moveable between a closed position in which the collector panel is supported in an inclined position and an opened position in which the collector panel provides access to the interior of an associated duct section. 
     
     
         9 . The roof-mounted ventilation air duct of  claim 2 , wherein said lid is a solar panel. 
     
     
         10 . The roof-mounted ventilation air duct of  claim 1 , wherein each of the duct sections is adapted to be supported directly onto the flat roof by means of built-in legs provided on the bottom surface of each duct sections. 
     
     
         11 . The roof-mounted ventilation air duct of  claim 5 , wherein the duct sections have a generally triangular cross-sectional shape. 
     
     
         12 . The roof-mounted ventilation air duct of  claim 1 , wherein at least some of said plurality of duct sections have a sheet metal separating the fluid passage in said duct sections in a first section where incoming air is drawn into the building and a second section where outgoing air from the building is expelled, wherein said first and second sections are in heat exchange relationship. 
     
     
         13 . A building comprising:
 a flat roof;   a ventilation unit mounted on said flat roof; and   a roof ventilation air duct seated directly on said flat roof and operatively connected to the ventilation unit, the ventilation air duct comprising a plurality of duct sections adapted to be connected end-to-end in fluid flow communication to form a fluid passage for allowing air to flow therethrough,   
       wherein at least some of said plurality of said duct sections have a seat within the fluid passage for receiving a ballast material, the ballast material anchoring the duct sections to the flat roof, the duct sections and the ballast material having a combined weight which is selected to render said duct sections immovable to side winds on the flat roof of the building. 
     
     
         14 . The building of  claim 13 , wherein at least some of said duct sections further comprises a lid to provide access to the seat. 
     
     
         15 . The building of  claim 13 , wherein said ballast material is a thermal mass being in heat exchange relationship with the air flowing through the fluid passage. 
     
     
         16 . The building of  claim 13 , wherein at least some of said plurality of duct sections have an air heating panel coated on an outside surface thereof with a solar radiation absorbing material. 
     
     
         17 . The building of  claim 16 , wherein the air heating panel is perforated. 
     
     
         18 . The building of  claim 14 , wherein said lid is a solar panel. 
     
     
         19 . An air duct section adapted to be connected to a ventilation unit of a building comprising:
 a body extending from a first open end to a second open end and forming a fluid passage for allowing air to flow theretrough, said first and second open ends being adapted to be connected in fluid flow communication with first and second similar air duct sections, respectively;   a seat within the passage; and   a ballast material adapted to be disposed on said seat within the fluid passage such as to be in contact with the air flowing therethrough,   
       the duct section and the ballast material having a combined weight which is selected to anchor by gravity the duct section to an underlying support surface. 
     
     
         20 . The duct section of  claim 19 , further comprising a lid between said first and second end of said body to permit direct access to the seat. 
     
     
         21 . The duct section of  claim 20 , wherein said ballast material is a thermal mass. 
     
     
         22 . The duct section  claim 21 , further comprising an air heating panel integrated to said body.