How to easily include rafter tails

Am I missing something or did I really not notice until now that the rafter module doesn’t have an easy way to add a rafter tail to a simple rafter design? Position 0 defaults at the low bearing so the user has to manually calculate dimensions along a rafter to get both support locations and adjust accordingly.

Related: it seems like it would be easier to add support locations if they were based on a horizontal plane rather than the length along the rafter. It would then also be easy to model the tail by simply setting the first support location at 12in (1ft), rather than doing the math to figure out the distance along the rafter.

And lastly: the graphic for span length defines L as the total plan length, but it doesn’t appear to actually be that way for rafters. Enter “L” for a support location and the value is based on the longer actual length of the rafter on the incline, not the plan length.

Hey @WilsonEngineers ! Thanks for the post! You’re right - how we deal with rafters (and inclined beams in general) can definitely be improved. That’s something we’re working on - but in the meantime, here’s so guidance I can offer on how things work:

  • Beam length is always entered in the plan dimension. We handle the conversion to the total length based on the roof pitch.
  • Support location, however, is entered along the length of the rafter
  • Load locations are entered along the length of the rafter

There’s one exception to these rules: our roof tie calculator. In that one:

  • Span length is entered in plan dimension
  • Eave length is also entered in plan dimension
  • Load locations are entered along the length of the rafter

I acknowledge that this is… confusing at best. We really want to improve this! From your post here and other users’ comments, it sounds like the best option is to have everything in terms of plan dimension. Stay tuned!

Thanks for the heads up on the diagram, by the way. We’ll look to update it.

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