Lumber grades for analysis
Lumber grades for analysis
(OP)
Which of the lumber grades, on, e.g., http://euler9.tripod.com under "Lumber Mechanical Properties," "Table 1," "2 x 6 inch," would be used for the rafters of a typical moderate or low-priced house or inexpensive wood-frame small commercial building? All pine lumber I see at stores such as Home Depot appears to be grade 3, I assume, even though it's unmarked and has few knots. The best pine lumber even at typical professional lumber yards is designated grade 3, I believe, even if it appears to have virtually no knots in most pieces. Which one of the grade delineations (rows) listed in the above web page table, for 2 x 6 inch, would be most likely for the described rafters in the described, typical construction most of the time?
The same question goes for the joists (and the same question goes for the studs in the typical stud walls supporting the roof, if you have time). Anything you can tell me about (or to define) the many grade name delineations listed on the above web page, as they relate to the real world and typical low-budget or subdivision project housing construction most of the time, would be greatly appreciated. I assume the strength values listed on the above web page include a factor of safety. If so, what factor of safety would you guess is built into those strength values? I couldn't find it yet on that web page nor in NDS for Wood Construction manual. Thanks.
The same question goes for the joists (and the same question goes for the studs in the typical stud walls supporting the roof, if you have time). Anything you can tell me about (or to define) the many grade name delineations listed on the above web page, as they relate to the real world and typical low-budget or subdivision project housing construction most of the time, would be greatly appreciated. I assume the strength values listed on the above web page include a factor of safety. If so, what factor of safety would you guess is built into those strength values? I couldn't find it yet on that web page nor in NDS for Wood Construction manual. Thanks.






RE: Lumber grades for analysis
Lumber for houses is a good question. Austrian spruce is really nice... A good resource is the Southern Pine Council's web site: http://www.southernpine.com/. They even list manufacturers.
My take on Home Depot lumber: beware of moisture content. Assume you will have noticable shrinkage within a couple of months.
RE: Lumber grades for analysis
Check Southern Pine Inspection Bureau (SPIB) grading rules.
RE: Lumber grades for analysis