Scribe rule barn - hard vs soft wood - where and why?

[JimXJ2000]

We have been working on our project to turn a late 1700's English barn into a living space addition.  I've enjoyed it (but it would be nice to be done) and enjoyed learning about the framing.  The barn was a 7 bay, principle rafter English style. 

For the most part I have been able to figure out (at least a good enough reason for me) why some parts are soft wood others are hard wood.  For the old frame we are using the posts,  tie beams, plates, and grits are all softwood (mostly white pine).  The struts, wind braces, plate (flying?) purlins are all hard wood.  That all seems logical to me. 

Except the gable end bents were all hard wood; post, tie beam, rafter and "studs" were all oak.    Also the posts where the two plate sections joined (one plate was 4 bays, one three bays) was also oak, but not the rafters on this bent.  The posts tended to be smaller than the pine posts but the tie beam was a bit larger.  But the rafters were significantly smaller (which might be ok with 3 "studs" going from the tie to the rafter instead of one strut). 

For loading the end bents would seem to have less load than the middle sections, so they wouldn't need to be stronger. 

Any ideas on why to use hard wood for these couple posts, ties, and rafters?

The picture shows the middle section where the two tie beams meet. 



 

(Some other pictures in my album show the later modifications that cut the ties, added what I call queen posts, and extended the rafters to widen the barn.  That was a mix of hard and soft wood, but didn't seem to follow a pattern.  The old work did seem to follow a pattern.  )

[Dave Shepard]

It may have been as simple as that was what they had. The Dutch barns that I have seen and worked on were primarily pine, with hardwood braces.

[JimXJ2000]

That may be the case, but it seems to be deliberate.   Everything else is very consistent in the old parts of the barn.

[Heartwood]

If white oak, maybe it was for rot resistance on the gable ends.

[JimXJ2000]

They were white oak (as best I can tell).   They actually were in worse condition than the white pine.  But that could have been more because of the location than the material.