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Painting new wood to protect from elements

Jamie K | Posted in General Questions on

Hi there!  First question, I applied primer on our new exterior pressure treated (PT) wood posts (per paint lady’s recommend) that hold up outside lean to section of trusses – then found out PT wood takes 6-8 months to dry out.  I’ve been told that the paint may not stick and peel off, but will that primer being applied so early rot or cause any other damage to those posts?

Secondly, for the Douglas fir kiln dried beam above those posts as well as the exterior wood door trim (on brick mold fiberglass door, no idea what kind of wood just came coated with something white), I need to get those primed with 2 coats of paint before winter correct, to protect from elements even though they are both covered by at least 2 ft of overhang?
Do I need to take any moisture content reads before doing so to ensure they are below a certain % or since they came in dry of summer and have been under 2 ft of overhang they should be fine?

Thanks in advance! 🙂

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Replies

  1. Expert Member
    Peter Engle | | #1

    The primer will not cause any damage to the posts. If it's been on for more than a week or two without bubbling or flaking, it is probably going to stick just fine. Even so, I would wait until spring to apply the finish coats. At that time, apply another coat of primer first, then your finishes.

    As far as the other untreated wood, you've got lots of options. I've seen untreated exterior wood that is protected from the elements last decades without paint. It turns gray, but doesn't really get rotten or otherwise damaged. However, if it is intended to be painted, it will be best to paint in the fall, when most of the country sees its best weather. Your account info says your are in eastern WA, and that's just about desert, so everything should be plenty dry by now.

    if you want to be sure about your results, it is always best to check moisture before painting. In your climate, exterior wood not exposed to any rain will probably stabilize to a moisture content of 8%-12%. If you have a moisture meter, use it. If the wood is showing more than 12% moisture, you should figure out how & why it is getting wet, or just wait a few weeks and test again. It would be best to prime and paint it before winter. If you are at high altitude, you also want to be careful of cold. You would like to have a day or two of drying time before any sub-freezing weather.

  2. Jamie K | | #2

    Hey, thanks for helping me, Peter - super helpful!! I want to make sure and note all our wood is brand new and just cut/delivered and framed/roofed within past month; so, it might hold more moisture still right? So, wondering if need to let it dry out more til spring to paint vs expose to to elements over winter...I'd like to paint before winter just want to make sure I'm not goofing it up again by sealing in moisture in untreated wood now recognizing my amateur level :)

    ...even so, the primer on the PT posts won't cause any mold? Why a 2nd coat of primer in spring - just curious? :)

    Isn't graying wood, surface mold or mildew?

    All I have is a surface moisture meter, will that work ok? Just make sure it's (and it still should be even though newly cut) less than 12% moisture before painting as don't want to seal any moisture content in above 12%?

    Paint store says make sure we have 50 degree or warmer day to paint, as it's getting cold up here - does that sound right above that temp for a couple days to properly dry?

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