Structural wooden joist

Abstract

The structural wooden joist described comprises an elongated lower chord, an elongated upper chord and an openwork web structure joining the chords and consisting of a series of connector members formed of inclined branches and adhesively secured to the lower and upper chords. Each branch of a connector member is formed of at least two planks having contiguous sides adhesively joined to one another. The connector members define a series of triangular openings in the web structure.

1 . A structural wooden joist comprising: 
 a) an elongated lower chord;    b) an elongated upper chord in a spaced apart generally parallel opposed relation to said lower chord; and    c) an openwork web structure joining said chords; said web structure comprising a series of connector members formed of inclined branches and adhesively secured to said lower and upper chords; each said branch of said connector members being formed of at least two planks having contiguous sides adhesively joined to one another; said connector members defining a series of triangular openings in said web structure.    
     
     
         2 . A structural wooden joist as defined in  claim 1 , wherein each said opposite ends of said web structure displays a laminated panel; each said laminated panel being formed of a series of elongated vertical planks secured edgewise to one another and having upper and lower sides thereof adhesively joined to said upper and lower chords.  
     
     
         3 . A structural wooden joist as defined in  claim 2 , wherein each said connector member at each opposite end of said web structure is adhesively joined to a chord member and to an innermost plank of said laminated panel.  
     
     
         4 . A structural wooden joist as defined in  claim 1 , wherein said connector members of said web structure have upper and lower edges secured to said chords by finger joints.  
     
     
         5 . A structural wooden joist as defined in  claim 2 , wherein said planks of said connector members and of said laminated panels are glued edgewise to one another.  
     
     
         6 . A wooden structural joist as defined in  claim 1 , wherein said web structure further includes a central region free of connector members.  
     
     
         7 . A structural wooden joist as defined in  claim 6 , further comprising a laminated panel structure in said central region; said panel structure defining an uninterrupted surface having opposite lower and upper sides adhesively joined to said lower and upper chords respectively; said panel structure of said central region being formed of a series of vertical planks secured edgewise to one another.  
     
     
         8 . A structural wooden joist as defined in  claim 7 , wherein said planks are glued edgewise to one another.  
     
     
         9 . A structural wooden joist as defined in  claim 1 , wherein said planks are made of kiln dry wood.  
     
     
         10 . A structural wooden joist as defined in  claim 9 , wherein said wood is selected from the group including fir, spruce and pine.  
     
     
         11 . A structural wooden joist as defined in  claim 1 , wherein fibres in said planks extend in the longitudinal direction of said planks.  
     
     
         12 . A structural wooden joist as defined in  claim 1 , wherein each branch of said connector member extends obliquely at about 35° relative to said chords for a joist having a height of about 9.25 inches.  
     
     
         13 . A structural wooden joist as defined in  claim 1 , wherein each branch of said connector member extends obliquely at about 42° relative to said chords for a joist having a height of about 11.25 inches.