Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

how many 2x8,s do I need

  • Thread starter Thread starter -
  • Start date Start date
Status
Not open for further replies.

Guest
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.
 
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.
 
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.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top