Joining roof joists

16 Feb 2012
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South Glamorgan
United Kingdom
hi guys I’m after some advice

If I HAD to join two length of roof joists together <flat roof, just for a garage> (I know not ideal either way)

Which of the two ways below would you do it (or do you have a 3rd)


Apologies for poor photo, Would you push the two length together then use metal brackets (or timber offcuts) to hold them together

Or would You overlap by approx 1m and then bolt through,

They aren’t holding any significant weight long term just Osb board and EPDM
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One recognised method for joining two pieces of timber in the your option 1 is to "sister" them, that is with timber either side of the pieces to be joined, bolted through and using timber connectors.

Probably cheaper quicker and wiser to get a single length of timber of sufficient dimensions and grading to take the load.

how wide is the garage
both will end in tears plus gang nailed timber is done by a press
Overlap, coach bolt using mudguard washers on the outside and star washers between the sistered parts. Don't go too near to the ends with the bolts
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Joining timber for what, a 3m wide garage? o_O

You could use 500mm spice plates, but that would cost more that twice as much as a 3m joist.

If you don't want it falling on your car .....
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