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geordonp

Green Garapa (new boards with mold?)

Geordon
13 years ago

I started my deck last year, and purchased over 1000 lf of Garapa decking, which has been stored in my garage since last spring. The boards look fine, with a nice color in the stack. I wanted to do the EFC-38/Citralic/TWP steps before installation, so took my first group of boards (16) outside today. They looked fine in the sun, though I could see a few green spots on several boards when I sprayed with EFC (3 oz/gal). I used a deck brush to agitate, as I don't have a pressure sprayer. I then washed off with a garden hose.

I took a break for lunch and went back to apply the Citralic, and to my dismay, most of the dried boards now had a green tint to them -- I assume from mold. I went ahead and sprayed the boards, brushed, and hosed off. They looked pretty good wet. Now that they have dried, the green hue seems to be gone.

I am still concerned that the mold may still be in the wood, and if I apply TWP, it will be that much harder to get it out later. Do I need to do EFC in a higher concentration and leave on longer? Do I need something else? How should I proceed with the 16 boards I have already done, and all the ones I have yet to do?

Thank you.

(I am in Michigan, if knowing my climate helps in your answers.)

Comments (6)

  • john_hyatt
    13 years ago

    Garapa is a klin dried product. Its possible it picked up the mold from the relative humidty in your garage.

    Its a lot more work to prep the material before install but what the hay you have already started may as well keep going. Just keep doing the prep till the mold is gone. Or install the material and deal with it the easy way. J.

  • Geordon
    Original Author
    13 years ago

    Thanks, John. I know it is more work the way I am doing it, but I wanted to do both sides the first time. At this point, I am less worried about my time commitment, and more that I get this right without losing all my wood.

    You confirmed what I thought about the garage being the culprit. If the wood is still green after EFC, does that mean I should do it again?

  • john_hyatt
    13 years ago

    I love Guys like you.Not worried about time commitment. I am going to remember that one.

    Your not going to be losing all your wood Garapa could sit in 10'' of slime and be the same inside for hmmmmmm 50 years or so.

    Time,Labor is no problem at all....Ok Set up a tarp outside and a couple of saw horses one by one use a hand scrub brush and a 5 gal bucket of Oxalic wash,no need for the stripper there is no finish on to strip off, put on some gloves and scrub,rinse, scrub, rinse, scrub,,, well you get the idea. Rinse again be very sure no oxalic is left on the lumber and take that one to the covered area where you have fans set up and stack it up with stickers. Be sure and do both sides and the edges. Do the next one. Be sure and keep them straight and leval.

    After 15 days or so with the fans runing,check everything every two hours, one by one sand all four sides with a makita 5'' random orbit 100 grit pads. Reason for this is that much oxalic is going to whisker up the Grappa. While sanding be sure and keep the edges beval the same, be very carefull. Stack each one up with out the spacers straight and leval. Bubble wrap the whole stack quickley keep all moisture out of the wrap, you can hook up your home vac to the wrapp as you go to suck out the air. Attention!!!! do not let the Sun hit this package.

    You now have a not bad stack of Lumber. Very close to the way it was delivered to You in the first place.

    But your not done Yet,,one by one take each one out Almost done but because you have stickerd it up you will have sticker Marks!!! Dammmmmm so sand it again with 120 grit be very carefull again, and install it. You will have to keep the vac going and close the wrapp each time thats a lot of duck tape but Hey!! youve gone this far Right??

    After you have gone thru all of this there is a very good chance the project will look close to the same as installing the material just as it is then brushing it off with a deck broom and a light oxalic/water mixture. JonMon
    Edit...

    Now if your intention was to pre finish all four sides before install there are a few more steps to go through. All of them would be as useless as the rest of it.

  • tcian
    13 years ago

    Follow John's instructions to the letter....especially the last sentence. Install the Garapa, clean if you must, let dry, stain with TWP, have a beer. I did my tigerwood deck in april in Michigan and it came out beautiful...read everything that John has posted...when it comes to decks, John is the expert.

  • Geordon
    Original Author
    13 years ago

    You had me freaking out there, John! (thanks for the pointer, there tcian.)

    What exactly kills the mold? The EFC or the Oxalic?

    If I leave the wood as is and install it, then Oxalic and TWP (thanks for all the help with TWP 100 last year), that gets the mold off the top, right? But what about the bottom?

    Or, could I simply do all four edges with Oxalic on a short stack, give them a hour or two to dry, then drew them down on the deck.

    Or are you saying the mold doesn't even matter? Just install, and go on my merry way prepping and applying TWP to the top?

  • john_hyatt
    13 years ago

    Mold spores never die they just stop working for a while.

    The cirtic stripper's job is to remove old finish. The oxalic wash preps the wood and puts the stripper into netural.Nither one is set up to kill mold. The scrubing and rubbing removes the mold you can see.

    Gordon you must have a real bad case of mold to warrent this much worry,Man what did your garage smell like?? I recomend to You a good cleaning using the oxalic,as little as possible, hand work with a scrub brush rinse off with the hose. Like I said the more oxalic/brushing the more the garapa is going to whisker up.

    Garapa is klin dried its going to soak up water. Garapa is also know to through a fit before it gets installed exposed to a lot of water/Sun light just be careful,use the sprit of a sound mind,remember your not killing snakes and chill out. J.