Ozarks cabin

[Belafonte]

I am planning to build a small timber frame(8x12 or 10x16) to use as a cabin/micro cottage here in Oklahoma.  I have a stack of southern yellow pine 6x6's I milled this winter that I would like to use for the posts but I'm afraid they might be a little small if I use the plans from Will Beemer's new book Learn to Timber Frame as the basis for the design.(great book by the way)  The plans call for wedged half dovetails on the tie beam to post joint so this would leave 1.5 and 3 inches on each side of the mortise which is in line with some of the design rules i've read on this forum(1/4 thickness).

The plans use white pine 7x7 with a snow load of 50psf. Would the added strength of SYP over white pine, plus having a snow load of 10psf vs the 50psf that the heartwood frame is designed for give me enough leeway to use the smaller timbers?  Could I downsize the plates to... say 6x7 as well?   

It will have a loft and I will most likely be finishing it with a lightweight roof like Ondura or metal and wrap and strap for the walls.   People build pole barn houses around here all the time and they are frail looking compared to a structure this small with 6x6 posts so I can't help but wonder.   Any help or vote of confidence would be appreciated.

P.S.  I will be building it in the county with no codes to jump through, but I do not want to build a weak structure either.

[Roger Nair]

As a matter of theory, yes or no.  BUT, designs need to be drawn and specified and then deserve experienced review and calculation before any kind of go ahead is issued.  You will have conditions in OK, such as tornados, that a designer in western Mass may not contend.  You may need longer end distance on tenons to deal with larger wind loads or some form of hurricane strapping.

[Belafonte]

Thanks for the reply, Roger.  I think I kinda expected this answer.  :D  It's somewhat foolish of me to ask on a forum for someone to give their approval of structural adjustments on an inhabitable building like this.  There is a lot to consider as well as liability and all these days.  It's probably best to talk with the designer personally.