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Framing lumber grades

chrislene | Posted in General Questions on

Gut reno. My engineer specified DF#1 for all framing lumber. My builder used DF#2 lumber for all framing. Is there a structural issue?

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  1. Expert Member


    It doesn't matter whether we think there may or may not be structural issues. If your engineer specified DF#1, that's what had to be used.

    1. Expert Member
      DCcontrarian | | #3

      More broadly, this is the framer's goof and it's on him to make it right.

      I would say a reasonable solution would be for the engineer to go through the plans and redo the calculations for #2 instead of #1. Where there are problems, the two of them would work together to come up with solutions. This would all be at the framer's expense.

      1. chrislene | | #7

        Yes, the engineer is going to review. There has already been one review because the framer (and builder) ignored many of the engineer's plan details.

  2. freyr_design | | #2

    A lot of engineers don’t understand how hard it is/ impossible it is to source #1 grade 2x material. As Malcolm said it doesn’t matter what people on here say you need to make sure your engineering calcs with no 2. Most no 1 lumber gets used for appearance grade lumber. That being said, beams and post are almost always specified no 1 and are easier to get in that grade (though still expensive) so that is what should be used.

    1. chrislene | | #11

      At the very least, the builder should have a conversation with the engineer and not just go rogue. I doubt that in this case the builder even noticed. It was the framer - for whom the builder is responsible. This is a builder well known in the bs community.

      1. freyr_design | | #13

        Agreed, it should have been a 5 min conversation and if it was edge case engineer would have probably suggested fix right then (lvl, tighter spacing…).

  3. Expert Member
    DCcontrarian | | #4

    I just reread the original posting. "Gut reno" to me means that all interior finishes are removed, but framing remains. So are you saying when the house was built it was built with #2? Or is the #2 new construction as part of the reno?

    In either case the engineer needs to go back over the calculations, it's just a question of who's on the hook for it.

    1. Expert Member
      MALCOLM TAYLOR | | #5


      Good point.

    2. chrislene | | #6

      Gut reno really is more of a new construction. Only a few exterior 2x4 stud walls remain. Is is unusual that the builder did not notice/care that the framer ordered and installed #2 lumber? The build lets the framer order materials from the lumber yard himself. No oversight.

      1. Patrick_OSullivan | | #8

        > Gut reno really is more of a new construction. Only a few exterior 2x4 stud walls remain.

        Semantics. That's more of a reconstruction, in most people's minds. Typically "gut reno" means the exterior shell remains.

        > Is is unusual that the builder did not notice/care that the framer ordered and installed #2 lumber? The build lets the framer order materials from the lumber yard himself. No oversight.

        Let me rephrase: "Is it unusual that the builder lacks attention to detail, strong management of subs, and high cohesion of end to end detail from design to implementation?"

        No, it's super common! Unfortunately, I'd say most builders at horrible at this. So, while it isn't your fault, it is your problem, as the saying goes.

        If it makes you feel better, in the theme of "if a tree falls in the forest...", I'm sure many buildings are spec'd with #1 lumber that get built with worse and no one ever knows.

        Your builder should have caught it. Your engineer should have more connection with what's actually sold in lumberyards.

        In reality, I suspect most of the design will work with #2 and better. If the engineer was really designing on the edge of #1, it's not a great design, practically speaking.

      2. Expert Member
        DCcontrarian | | #9

        Can you tell us more about what was added on?

        Broadly speaking, the grade of the lumber is only important in things that are horizontal or somewhat horizontal -- joists, beams, rafters.

        1. chrislene | | #10

          Everything was added on... expanded first floor, entire second floor and 16" I beam roof rafters over attic. This is a poorly planed double stud wall project. triple pane tilt turn windows and doors all have to be removed and reinstalled (installation pics in sep post). So many issues too numerous to list. The lumber grade was just the most recent that I noticed. Builder fired and trying to move forward with remediation.

        2. Expert Member
          BILL WICHERS | | #12

          Certain columns can also be an issue, depending on the loads they are carrying. As a simple rule of thumb though, columns (which can include things like king and jack studs, BTW) critical enough to be specced with "fancy" lumber are usually also under something "fancy" that is horizontal, like a big LVL beam.

          If the engineer specced #1 lumber in non-loadbearing locations, it probably won't be any problem at all to change that on the drawings. You WILL need the engineer to change things for it to pass (and make sure it's safe) though.


  4. Expert Member
    Michael Maines | | #14

    The difference between grades is mainly the angle of the grain relative to the edge and the size and type of knots. In many cases the difference doesn't matter a lot, but in other cases it's very important for long-term safety of the structure.

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