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The contractor I hired is using these PT Douglas Fir joists. They look old. he says they are structurally sound just discolored. I took a screwdriver and poked the joist and it did not sink in at all. very hard. he said he is going to cut off the split ends. I am concerned as to why the wood looks burnt.

Can someone look at the images and let me know if they look ok?

enter image description here

enter image description here

enter image description here

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    If the contractor used "new" pressure treated lumber being sold today, you could expect considerable shrinkage as the lumber dried to normal water-content level. If the screwdriver test tells you it's hard wood (not spongy, etc), the lumber is fine. I'd a lot rather have old fully cured wood to build with, regardless of discoloration, than new wet pressure treated lumber. New takes 6 months to a year to dry and shrinks quite a bit. A pressure washer can always take care of the discoloration. Commented May 5, 2022 at 1:28
  • This is not burned, just what wood looks like after it has dried (often in the sun) for a while.
    – TylerH
    Commented May 5, 2022 at 13:45
  • I assume the asker used it as a figure of speech. Burnt wood would look charcoal black (because it has turned into charcoal) :)
    – MiG
    Commented May 5, 2022 at 16:12

4 Answers 4

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I took a screwdriver and poked the joist and it did not sink in at all. very hard.

That's your key right there. There's nothing wrong with the wood, it just doesn't look very pretty.

If it were bright and blond and "new" looking, well, it wouldn't be pressure treated. Pressure treating will make the wood dark like that. Those look a little darker than what I'm used to seeing but they look just fine.

I'm sure your contractor will cut a 1/2" or so off the ends of most boards to square them up, and will probably cut enough off the ends to get rid of the bit of split that's formed (and is a natural occurrence when wood dries), but otherwise, you're just fine.

Far more important is that the boards are reasonably straight and not warped. It's possible your contractor might find a board or two that is too warped to use, and he should set these aside, but some amount of bow and twist is acceptable. Usually they get returned to the store for a refund if they're too far gone.

Once the wood has been outside for a year or so as part of the deck, it will begin to weather to a much lighter grey color.

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    I would also suggest that the newly cut ends are treated with preservative.
    – Peter bill
    Commented May 4, 2022 at 20:33
  • And warped/twisted boards are also useful if cut to smaller sizes to use for cross blocking or other shorter spans where the warping is mitigated.
    – TylerH
    Commented May 5, 2022 at 13:47
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The other answers addressed the appearance of the wood with great accuracy so I'm not going to beat that dead horse.


Are you getting a good deal on the deck? These boards could have been purchased pre-covid for less than 25% of today's prices so if you were quoted for materials using current prices then the contractor is pocketing the difference. Heck, for all we know these boards were abandoned somewhere and the contractor took it upon themselves to "find" them.

However, labor prices have also skyrocketed so if material costs weren't disclosed upfront then the contractor could easily pad some numbers if you're asking for a cost breakdown retroactively.

If pressure-treated wood lasts about 40 years as a deck then these boards may have lived through 3, 5, or more of those years already. Is that something you're willing to pay full price for?


After having a second look at your question, the workmanship is a bit concerning.

enter image description here

Additional issues have been identified after I created the picture so here is the full list below containing my observations and those of the comments section:

  • Missing post-cap ties are a big concern for me
  • V-dip in the beam supporting the rim joist end of the deck
  • The beam in the middle of the deck appears to be just a 2x8 holding up an 4x4 and doesn't even span the entire width of the deck
  • I didn't see any tension ties to tie a couple of the joists into the house, through the ledger board

I highly advise getting this thing independently inspected.

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    @Astrogator I was hoping that OP would chime in just saying it's just an issue with a wide-angle photo but we really don't know unless another picture is provided. Also, the absence of post cap ties joining the posts to the rim joist is another big concern. I reall hope OP is getting this thing independently inspected.
    – MonkeyZeus
    Commented May 3, 2022 at 15:46
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    agreed the V-dip seems to be a corner. Looks like the left beam extends beyond the joists... maybe just incomplete on the corner? The center beam far end appears to be sitting on a nailed cleat. Hard to be definitive from the picture, but looks like some nails are missing in the joist hangers. This is not how I'd frame this as an amateur, and I'd be saying a hard no to any pro that framed my deck with such a random collection of columns, beams, and (lack of) ties.
    – Doug
    Commented May 3, 2022 at 16:22
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    @MartinBonner Lots of contractors are not very good at the business side. They buy lumber to finish your job with the down payment from a new job. For those types, using old lumber at full price is a windfall.
    – user19565
    Commented May 3, 2022 at 21:06
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    I think your 20 year life estimate is way under. For pressure treated, up in the air where it will stay mostly dry, you're looking at decades longer. 75 years even.
    – user19565
    Commented May 3, 2022 at 21:12
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    Hey, at least they put joist-hangers on the side connecting to the home. Commented May 5, 2022 at 1:23
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To answer your specific question, “are these okay?”, yes.

They may have been sitting outside for a while, but there aren’t going to be any structural issues. Once built, you won’t really be able to see much of them, so the aesthetic issue will go away as well.

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That's just how aged Douglas fir looks like: it gets really dark after a while. But that's a good thing, the oxidized layer protects the inner structure.

I built a DIY table with Douglas fir 2 years ago:

fir wood table - before

After 2 complete years outside, it now looks like:

enter image description here

Granted, it doesn't look very good, but it's now protected and the structure will look just the same in 5 or 10 years.

The wood shrunk a bit, and sadly, there's now enough space for forks to fall down.

Which means it's better to use Douglas fir for building a structure once it's already weathered.

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  • Your table wasn't built of PT lumber in the first place, so the treating will contribute to the darkening.
    – FreeMan
    Commented May 5, 2022 at 11:37
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    On the plus side, the added space will help to reduce crud accumulation in between cracks on top of the support beams. Accumulated crud holds in moisture and speeds up the rot process. Looks great though! Here is a picnic table I built just 2 years ago i.sstatic.net/iWi03.jpg and today it definitely looks like your second picture.
    – MonkeyZeus
    Commented May 5, 2022 at 12:54
  • @MonkeyZeus: Wow, color me impressed. The picnic table looks really good, very stable and professional. Do you have more info about it? Commented May 5, 2022 at 13:13
  • @EricDuminil Sorry, in a meeting now but I'll be happy to provide more info/pictures when I get a chance!
    – MonkeyZeus
    Commented May 5, 2022 at 13:57

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