rafter cable ties

Discussion in 'General Home Improvement Discussion' started by paulmars, May 31, 2014.

  1. May 31, 2014 #1

    paulmars

    paulmars

    paulmars

    Member

    Joined:
    Feb 19, 2013
    Messages:
    21
    Likes Received:
    0
    I cant understand this math. ive been over and over it. Each time I get a little further, then I loose it again.

    ref:
    How to calculate rafter thrust? -Help! at http://www.eng-tips.com/viewthread.cfm?qid=105386

    Can someone help me figure cable load?

    4/12

    24" rafter spacing.

    No rafter ties at all. A few existing collar ties.

    ceiling joists run parallel to ridge.

    house is 27' x 30'(ridge).

    7/8" roof planking and asphalt shingles.

    thanks,
    pa
     
  2. May 31, 2014 #2

    nealtw

    nealtw

    nealtw

    Contractor retired

    Joined:
    Nov 4, 2010
    Messages:
    23,892
    Likes Received:
    3,117
    You might need an engineer for that but (and it's only a thought) If the ceiling is running in same direction, the whole thing is held together with 3 or 4 nails where the joist attach to the outside wall. So what is the shear strength of 8 3" nails
     

Share This Page