Sawing Your Own Framing Lumber

Proper grading is an issue, because knots may weaken the material for structural purposes. April 20, 2011

Question
I soon will have a new band sawmill with which to cut some eastern white pine, only some of which will likely yield high quality boards. My questions are: is the poorer quality knotty pine strong enough to use as construction lumber, e.g., as 2x4, 2x6's, etc.; and if rough sawn, air dried pine is used as siding, will pitch be a problem if semi-transparent stain is applied?

Forum Responses
(Sawing and Drying Forum)
From contributor P:
What you describe as low quality and knotty is what’s available at the lumberyard. Each piece of lumber has to be looked at for quality when building with it, even the store bought stuff. Sawyers who use their own lumber get more knowledge of what works. Spike knots steal more strength than round knots do. You will probably find out like I did, you get a lot of unusable and some good.



From contributor B:
As long as there are no obvious defects: shake, insects, or rot you can use the lesser grades for many things around the home. Pine furniture, timberframes, and siding are uses around my place!


From Gene Wengert, forum technical advisor:
Sap will ooze from the lumber if it is not dried (or heated) at a temperature over 150 F or so for at least 24 hours. Most finishes do not stop this sap bleeding.

Regarding the use for construction lumber, such as for a home, the knotty material may be strong enough, but most structures that are used for human occupation will require graded lumber. The grades require special knowledge and application of this knowledge to assure that the knots that are present do not weaken the piece too much. Very few states allow you to cut your own lumber and use it for construction of a home or other building without having the wood graded.




From contributor P:
I started this house in NH four weeks ago. It’s framed almost entirely out of white pine sawn from my mill.


Click here for higher quality, full size image



From the original questioner:
Impressive photo. Did you kiln dry the wood? If not, does the sap indeed ooze?


From contributor P:
I just air dried the lumber. There is pitch on some of the lumber, but not really a problem for framing.