which is better? 4x4 or 2x6


Old 01-01-07, 08:01 PM
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Question which is better? 4x4 or 2x6

I'd like to add a 16' long beam under my 1st floor joists to help stop the bouncing. Which would be a better choice? A single 4x4 or a single 2x6?
Old 01-01-07, 09:12 PM
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Neither is strong enough to help much, unless you are supporting it with columns every 4'. But by comparison, a 2x6 would have more vertical support than a 4x4.
Old 01-02-07, 07:13 AM
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I had the same problem with the living rm addition on my house [built prior to my purchace] A carpenter friend advised me to support the middle of the joists with a 4x4 supported by block. I went 1 step better and used a 2x4 and 2x6 nailed together with the 2x6 notched every 16" to accept the floor joists. The floor is now very solid
Old 01-02-07, 09:12 AM
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another option, depending on how much electrical or plumbing is run through the joists in the area you wish to strengthen, is to sister joists to your existing ones. To be effective they don't need to run the full length, and they don't need to be the exact same size as the exisiting ones. They do have to be glued and nailed into place. The purpose is to reduce the flex of the floor joists.
Old 01-02-07, 04:07 PM
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I would use 2 2x6's nailed or bolted together on edge, with a support post at 8'. Good Luck
Old 01-06-07, 09:23 AM
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The single 2x6 is 68% stronger than the 4x4 for vertical loads as you describe. However, I caution you that it may be a good idea to have someone design this beam properly so the job is done right. If you're willing to have a 4" wide beam, why not create a double 2x6 beam, this will be 237% stronger!

(I know this stuff....I'm a licensed professional engineer)

Good luck!

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