How do you decide what grade of Southern Pine to use?
How do you decide what grade of Southern Pine to use?
(OP)
What's your typical decision process like for deciding whether to use No. 2, No. 1, Select Structural, etc. when specifying Southern Pine? Obviously less cost is preferable, but higher quality wood will need smaller members. Is it different for every job?





RE: How do you decide what grade of Southern Pine to use?
Check with your lumber supplier and see if they can get you a feel for the range of costs associated with their available grades.
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RE: How do you decide what grade of Southern Pine to use?
Be careful about relying on that reason. Note that the modulus of elasticity is normally constant for all grades. Even if smaller members are structurally adequate, deflection will be greater for the smaller member. You could wind up with a design that has excessive deflections.
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RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
Can you elaborate?
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
Spruce Pine Fir or Hemlock, Douglas Fir woods are more stable.
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
"...increasing amounts of lumber are being cut each year from young, small-diameter trees. Unfortunately, this material exhibits a high propensity for warp when it is dried."
Here is a link to the complete paper:
http://ir.library.oregonstate.edu/xmlui/bitstream/...
The Southern Pine Inspection Bureau (SPIB) does not address this tendency on their website, however, the Southern Forest Products Association does. In the FAQ section of the website the following question is presented: "Why does lumber sometimes warp and crack?"
Answer, in part: "...Warp is aggravated by irregular or distorted grain and the presence of abnormal types of wood, such as juvenile wood..."
http://www.southernpine.com/faq/
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RE: How do you decide what grade of Southern Pine to use?
All of this; however, is considered in the grading of the lumber. Further, the exposure of the lumber in the field and the way it is stored can have a significant effect on the individual boards and their propensity to warp or twist. Cupping is also a common issue, particularly with lumber widths of 6 inches and over. Look at the end grain of the piece. You will usually be able to clear predict its tendency to cup based on the grain. The more curved the grain at the end, the more chance of cupping.
RE: How do you decide what grade of Southern Pine to use?
This is what I would have expected. But, the way I am interpreting boo1's statement is SYP lumber in a given grade tends to warp/twist itself out of the initial grading classification, even in the best of conditions. Maybe the case for selecting a more stable species would be to *try* to mitigate effects from poor material storage onsite, or exposed framing prior to the enclosure of the building with vapor barrier and fenestration.
Would you agree boo1?
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
Lumber should normally be dried to a reasonable level for structural use. It should be kept under cover in transit, at the lumber yard, and on the job site, until it is nailed into place. And then, the building should be enclosed as quickly as reasonably possible, to minimize weather damage. Mostly, reasonable cost and local availability pretty much determine the grade of lumber that you normally use. Try not to use different grades of lumber on the same job, except for the obvious differences btwn. primary dimensional lumber and stud grade, because sure as hell the #1 or structural grade will end up being used for blocking and joists and those couple needy beams or headers will end up being made from #2 anyway. When several grades are used, this potential mix-up has to be controlled and managed in some way There has been a real significant deterioration in the quality of lumber being sold over the years of my practice, and we are going to have to get used to using this lower quality lumber being produced today, there just isn’t any old growth timber left to cut any longer. This also ushers in the greater use of manufactured substitutes for solid sawn lumber, which can be designed and manufactures to use the lesser grade raw material more efficiently. While some warping, cupping, etc. is figured into the allowable stresses and design methods, the biggest problem with these conditions might be finishing and installation of sheet rock, siding, cabinetry, windows and doors, etc. The carpenter has to pay special attention to weeding out the real crap and working with the rest. That is, putting all joists in with their crown up, all studs should bow in the same direction, and not too much, etc. And, who has the time or experience for that kinda stuff any longer?
RE: How do you decide what grade of Southern Pine to use?
Definitely agree with dhengr on the mixing of grades. You can't rely on the framer to keep track of two different grades; it all looks the same to the untrained eye - hence why it is better to specify one species groups and grade, and then use engineered wood where required. It should follow a similar logic for the engineered wood, e.g. do not mix strengths of particular styles of engineered wood. If you are specifying laminated veneer lumber (LVL), don't specify 1.8E and 2.0E LVL. But, it is common to have a mixed bag of engineered products, i.e. LVL, Parallel Strand Lumber (PSL), Glue Laminated Timber. They are very different in appearance, and can't be easily confused for one another.
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
Spruce and fir are less susceptible to dimensional anomalies than SYP; however, they also have lower material properties that require structural reconsideration. They are also less dense than SYP and will absorb more moisture, thus being more susceptible to rot.
RE: How do you decide what grade of Southern Pine to use?
Not sure where I mention otherwise.
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?
"It is imperative Cunth doesn't get his hands on those codes."
RE: How do you decide what grade of Southern Pine to use?
RE: How do you decide what grade of Southern Pine to use?