Which deck beam configuration to use?


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Old 03-17-19, 08:50 PM
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Question Which deck beam configuration to use?

Of these 2 ways, does it matter which to use? I don't see anything describing any reasoning in the awc guide.

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Old 03-17-19, 11:05 PM
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Neither, you cant have that little section on the right, if I read your dimensions right it's 23', make it one piece.
 
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Old 03-18-19, 09:20 AM
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I'm just talking about the middle part. Forget the end. Does there have to be a split at each interior post, or can the beam be one long piece and go over multiple posts?
 
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Old 03-18-19, 09:29 AM
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You do it with the least amount of joints possible. In your case you might break one side of the beam on one center post and then the other side of the beam on the other. That way the beam can't pull apart because it is half lapped.
 
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Old 03-18-19, 11:18 AM
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OK. Why is that exactly, mechanically speaking? It seems like the span is the span, regardless of continuity. Just asking for my own understanding.

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Old 03-18-19, 03:26 PM
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Let's say your span is 24 and your posts are 8 ft apart. (Not what you have but just as an example) Your beam could be made of 2x12s...

First 2x12: 8' + 16'
Second 2x12: 16' + 8'

Then fasten them together to make your 4x12 beam... that's a lap joint. Stronger and better than having an 8' beam, putting it up.... then a 16' beam and putting it up... each joint is still centered over a post but the joints are staggered and there is no way anything can pull apart during construction.
 
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Old 03-18-19, 06:42 PM
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Do the lap joints have to lie over posts?
 
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Old 03-18-19, 07:01 PM
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Yes, centered on the post.
 
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Old 03-18-19, 07:13 PM
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In my case, I'd do

14 10
8 16
14 10
 
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Old 03-19-19, 08:42 AM
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make it one piece.
If it's within the limits of available materials then one piece is the absolute strongest option!
 
 

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