soutern yellow pine vs. spruce

huangyhg

soutern yellow pine vs. spruce
i have a project that is several two story frat houses.  the design is complete and a contractor has been selected. the plans and specs call for southern yellow pine no. 2 for all framing.  the contractor said that syp has become a low quality product with twisting and shrinking causing the nail to pop out etc.  he wants to use spruce which of course is according to the nds spec is not as strong.  has anyone else heard of this problem with syp no. 2?  i suspect that this contractor has used utility grade or worse in the past and that is why he had problems.
the contractor is just trying to get by with less expensive lumber, i would guess.
you could contact the southern pine inspection bureau and discuss this with them.
if you switch species now that the design is complete you will have a load of work to do with resizing   
changing species may also affect the capacity of plywood/osb shear panels.  the ibc provides reduction criteria if the specific gravity of the lumber is less than that for syp or douglas fir.  
based on my experience, the syp is stable as long as it's protected during construction.  if it's left out in the weather and the moisture content varies alot, it does twist and warp alot.  douglas fir is my preference.
thanks everyone for your input.  i called spib as suggested above and they said syp market is not in decline and is the only species that is randomly tested each year to insure that the actual material properties match the published tabulated values. thanks again!
and to answer the question above yes we are requesting a redesign fee from the contractor to use spruce unless he doubles all the studs using the same spacing.
he is right.  but, he can use select or #1 and protect the wood (tarp the bundles).  if change of species is requested then a change order should be generated to pay for the additional work.
cheers