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how many 2x8,s do I need

how many 2x8,s do I need

how many 2x8,s do I need

I have a single family ranch. I need to remove a column in the basement. The original beam is 3 2x8,s with a cloumn every 7'-6'' floor joist are 12 ft long 16" oc. I want to span 16 feet can this be done with 16' 2x8,s along the existing beam? tail of floor joist is 4" past the original I was hoping to put 2 16' 2x8 on each side of the original triple and add columns to support.

RE: how many 2x8,s do I need

By the spanish practice your setup seems to need quite scarce, say 7 independently 2x8 in (all continuous from support to support) collaborating to take 12 ft of floor in a 16 ft span. If you can it will be more efficient to use members of more depth. You would be initally taking 1.4 tonne/m by the spanish evaluation, and to take the same with only 8" deep in the new 16 ft span would take a width of 28 in or 14 such 2x8 members, for a central deflection of a bit less than 1". The practice in your area may be less stringent. In any case, the recommendation of using more depth I see becomes from the evaluation quite clear.

RE: how many 2x8,s do I need

Er, the named deflection is at the end of the life of the structure. A divisor to initial stiffness of 5 has been uses to this purpose, so initial deflection will be scarcely noticeable.

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