There seem to be many different scarf joints, and I'm wondering which specific scarf joints work best for certain scenarios. Is there any literature or guidance for this?

The garage I'm building calls for ~23' long rafters (8x8) supported by purlin plates and eve plates. I'd like to use two timbers for one rafter and use a scarf joint over the purlin plate. Is there a certain scarf joint that would work best in this scenario?

The plates (both eve and purlin) are also very long and will require multiple scarf joints in each plate (8x10s). Seems that placement of these scarf joints is best over a knee brace rather than over a post. But once again, is there a certain scarf joint that would work best for plates?


Michael Hartke