quality of wood studs today

huangyhg

quality of wood studs today
much can be said about the quality - or lack thereof - of 2 x 4 wood studs these days. as an engineer, i find it quite disturbing. not only is the moisture content well above an acceptable level when delivered to the job site, also the stud profile is often about 75% of the expected profile. the expected 1 1/2" faces of the 2 x 4 are often reduced to nothing, leaving the contractor with nothing to nail to.
the solution i usually hear from the engineering community is: opt for steel studs or manufactured lumber. while these are good solutions, they do add significant cost.
why can't we tackle the problem head on? can we talk about what is causing the quality to be so marginal? i aggree that you get what you pay for; however, lumber that is cheap in cost need not be cheap in quality. it appears that we still have quality in the rest of the construction lumber market; but what about 2 x 4 studs?
i believe that the problem lies in regulation. if regulation of this product is handled at the state level - well, everybody knows that the state of california is nearly bankrupt. so, the producer of this product is allowed to sell a marginal product as if it passed regulation - because nobody is really watching them.
but what do i know? i am only lamenting what i see on the job site.
can we - as engineers - do anything about this problem?
-richard l. flower, p. e.

a bit ot
ten years ago during a radio interview a retired carpenter said the following:
"what we build houses out of in the 1990s was called firewood in the 1950s".
and, of course, ditto the difference between the 1920's and the 50's.  my parents' house was built in 1926, and not only were there no 2x4's even used, since the minimum sized stud was a 4x4, it was rough-cut at 4x4, e.g., much close to 4x4 than the current 2x4's are to being 2x4.
ttfn
hold on a minute before we forget that there are standards and grading rules for lumber.  rlflower, you mention that "the expected 1 1/2" faces of the 2 x 4 are often reduced to nothing, leaving the contractor with nothing to nail to."  the contractor bought that stud.  assuming the project quality criteria were properly laid out and the he is willing to follow building codes, studs such as this must be culled, if not at the supplier level certainly at the contractor level.  unfortunately you rarely see a carpenter "siting a stud" for sweep or camber anymore.  the pick up the next one off the bundle and pop it in place.  who gives a damn if the chair rail weaves in and out?!!
there are many grades of studs and lumber available....our job as engineers is to know the differences, specify the proper ones, and demand their use.  most of what is sold at major home improvement centers is not grade 1 or grade 2 and i have never seen structural select grade lumber at any of these suppliers.
further, most wood structure failures are not caused by poor quality lumber, but by poor quality construction, particularly with respect to connections.  "toenailing" in a tension connection was acceptable for many years.  due to more stringent wind load criteria, most nail fasteners for tension connections must be placed in shear, which requires the use of a plate or strap.  this is not because the wood is poor quality, it's because wood is generally incapable of sustaining a nail in tension under current wind load criteria.  take a look at video of some of the major hurricanes where you see the roofs being blown off houses.  many of them fail completely at the top plate, where it was nailed, not strapped.
regulation is not a solution, as finished lumber is manufactured in a host of states, and even countries, and regulation is usually a state or province issue.
no, the answer is in the specification, selection and quality control (at the end use location).
i once knew an old character who was real tight with the pennies, and when he was having a house built, he would meet the lumber yard delivery truck at every load, and cull the defective studs, boards, etc., and send them back to the lumber yard right on the same truck.
i don't think there was an imperfect board in his house.  but only because he made it happen.
rmw
we have our framers cull the studs, often its 1/3 of them.  they are used for blocking, rat runs, braces or sent back to the lumber yard.  consider ordering a better grade than stud grade or order from premium dealers like home dept.
as an engineer, you have a complete freedom to specify the better grade and low moisture content lumber, or factor in the moisture content in your calculations and evaluate the effect of shrinkage. but do not blame the state or the industry. if contractor does not follow the plans, then blame him.
the main reason bad plans pass the builiding department is that the law allows architects to seal and sign the structural drawings. when building department sees the stamps and scanty 1 page calculations (=garbage,without knowing what he is doing) prepared by the architect, they approved the plan as the architect is taking the liability by signing off the project. i fault the engineering professinal organizations for not protesting or not doing enough lobbying to the legistature, unlike the powerful aia.
to ensure quality, mention on the drawing that you must be notified for inspection/observation of framing & connections. regarding studs, you will never need to worry about their strength for 1 or even 2 story regular houses. shrinkage is very little along the grain, so you are fine even with green stud from home depot.
i have reviewed your posts and i thank you.
you have made me aware of a lack of regualtion for 2 x 4 lumber that is prevelant throughout the construction industry.
as an engineer, i can continue to lament the fact that there is little i can do about this. but i have a choice: do i "give up", or do i engage? i choose to engage.
if you were to write a specification for the contractor to read regarding quality control of lumber delivered to the job site, how would you word it?
-richard l. flower, p. e.
the lack of regulation is most likely due to the fact that >70% of lumber comes from other countries. canada being the main supplier.
if would seem your contractor should be inspecting his own purchase, specially if he's having trouble nailing to studs.  
another thing to remember is that what and how you specify your lumber (or anything else for that matter) directly affects the cost of construction.  so, first of all it is our responsibilty to know what we are specifing and how it affects cost, ask for it correctly with the right terminology, make sure it is available, and then provide enough inspection to be sure the right material is actually installed, ask for copies of the delivery tickets and look at the grading marks on the lumber.
ron hit the nail on the head (sorry, but i couldn't resist the pun), there are grading requirements the industry is suppose to adhere to.  and, with the stress grading of lumber, there is actually more assurance that if we get what we specify, it will perform.