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Engineering: Can't find the right span table

Posts: 39
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Hi Everyone,

I'm having trouble finding some information. I need to know how far 2X6 T&G pine decking (1200000 modulus) will span when laid flat, 4ft. O.C. at 100psf load, staggered layout, with L/240 deflection. I can only find span tables for joists, beams, and girders. I can find tables for decking but only for 6ft. O.C. and larger, nothing for 4ft.

Thanks Y'all
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Hi JP,

I  don't think I understand what you're trying to calc.

2x6 T&G at 4'-0" O.C. is spanning 4'-0".

Are you trying to find the allowable span at 100psf or the allowable load at a span of 4'-0" O.C.

I can run the calc for a simple span, though I don't know the calc for a staggered span.

The attached .pdf has all the common loading criteria, you can run the calc yourself using diagram 1 on page 4.

If you have any questions feel free to ask.
Filename: Structural-References.pdf
Description: Structural Calculations for All Common Loading Methods
File size: 10 megabytes
Posts: 51
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I don't like walking on any platform that has bounce....  so even 4ft OC 2" lumber is bouncy to me....

When I build decks, I never have more than 16" span for 2" lumber...   a nice solid feel underfoot.
Posts: 3072
Location: Upstate NY, zone 5
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The reasonable span depends on the application. If it is for a largely dead load like a live ( ) roof, bounciness is mostly irrelevant. If it is for a purely live traffic load, then bounce is relevant, even if deflection is okay.
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