top chord joist extensions - typical support condition

[hsustersic]

I have the condition where Type "R" joist extensions for K series joists have an extended span of roughly 4'-0".

Are tabulated load tables typically based on a simple span or a cantilevered span? I need to know if the closure piece that I am putting at the "free" end should be designed as load-bearing. Specifically, I am looking at Vulcraft joists.

Thanks.

 

[dik]

Generally for the simple support span distance and the joist end is reinforced for the cantilever... That long a cantilever can be a specialty item and the tables should be used for as a guide only.

Dik

 

[msquared48]

Agreed...

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[hsustersic]

I should clarify that I am looking at the "Top Chord Extension Load Table (R Type)" which tabulates top chord joist extensions of up to 6'-0".

 

[hsustersic]

The Vulcraft representative just got back to me - he said that the values in the "Top Chord Extension Load Table" are for a cantilevered support condition. Deflection must be independantly checked using the tabulated section modulus and moment of inertia.

Thank you for replying to my post.