Does anyone know?!

Discussion in 'Carpenters' Talk' started by John Bunyan, Oct 11, 2017.

  1. John Bunyan

    John Bunyan Member

    I posted about this the other week and no one replied. Can an 11 x 3 purlin be jointed in length because a full length cannot be taken into the loft without taking the roof off. Please, anyone??
     
  2. retiredsparks

    retiredsparks Well-Known Member

    Ask building control for advise.
    contact local big builders
    ask builders merchants if they have ever come across same problem.
    Send me some money and i will give you the answer...lol
    Look up flitched beams.
    RS
     
    Last edited: Oct 11, 2017
  3. retiredsparks

    retiredsparks Well-Known Member

    Funny how none of the 'builders' on here seemed to know ?;)
    RS
     
  4. retiredsparks

    retiredsparks Well-Known Member

  5. Isitreally

    Isitreally Active Member

    Yes it can.

    Cut it like this and bolt it together with steel plates on either side.

    half-lap-splice.jpg

    The BCO will have the final say though.
     
  6. retiredsparks

    retiredsparks Well-Known Member

     
  7. Isitreally

    Isitreally Active Member


    Hence the last paragraph. ;);)
     
  8. Jord86

    Jord86 Well-Known Member

    Yes. Either half lap it like Isitreally has posted along the width, or half lap it along the length say 6inches and connect with coach screws or bolts. Make sure the lap is under a rafter and you have installed struts supporting the two purlins either side of the join.
     
  9. John Bunyan

    John Bunyan Member

    Thanks all. Sorry I didn't mention the purlins are timber. 11 x 3. The guy who got the timber got the wrong lengths so I need to joint two purlins twice in the length!
    They are going about 4 foot underneath the existing purlins and then clad both sides with two layers of 9mm ply to form box beams for the new bedroom floor joists to hang off. Jord, do you mean like this.. services-roof-3.jpg
     
  10. John Bunyan

    John Bunyan Member

    this would be the easier joint, I mean what power tool could you use to do the width half lap apart from a recip saw? don't want to hand saw them!
     
  11. John Bunyan

    John Bunyan Member

    Looks like the overlap is twice the depth so in my case the 11 x 3 purlins would overlap 22 inch?
     
  12. John Bunyan

    John Bunyan Member

    What's the difference between carriage and coach bolts? do screwfix do 12 inch bolts appropriate for this? questions questions!
     
  13. Jord86

    Jord86 Well-Known Member

    A circular saw. Yes to your other question, I would use the joint in your picture if it was my house, in my opinion. Carriage and coach bolts one and the same.
     
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  14. dobbie

    dobbie Well-Known Member

    This is a scarf joint for a purlin.
    [​IMG]
     
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  15. Isitreally

    Isitreally Active Member

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  16. Jord86

    Jord86 Well-Known Member


    Jesus, haven't seen that since college days. Splayed scarf joint, also used to join ridge boards together if not possible in one length. Bit unnecessary today though with other methods of fixing.
     
    John Bunyan likes this.
  17. John Bunyan

    John Bunyan Member

    Just to be clear I said recip because you'd have to cut 11 inch deep, 5 1/2 from each side if you did the half lap the other way. I'll do it the other way with a circular saw as we both said.
     

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