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Minor mold/mildew issue?

1650 Views 7 Replies 7 Participants Last post by  ADHDan
I finished making a rolling plywood cart using some particle board that was left outside during a Minnesota winter. I didn't realize until I was halfway done that it has greenish spots all over it. There are no big patches, the drops don't seem to have grown or multiplied, and the board is now being stored indoors in my climate-controlled shop. I can post better pictures tomorrow, but suffice it to say that it basically looks like someone shook a paintbrush over the particle board and flung drops here and there. As you can see, there's nothing resembling the big patches of black mold you'd get from having something resting in standing water for a sustained period of time.

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Should I be seriously concerned? Can I leave it alone and see if it gets worse, or should I paint it down with Killz?


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I'd cover it if it was mine. No sense in inhaling any mold spores if it can be helped.
I work in Disaster Relief. This is not my area but I know we buy a product at Home Depot I believe. We dilute it according to the directions and spray it under in and on people's homes. I think we pay about $20 a gallon for it and you dilute it. I don't know if you can get smaller quantities or not. I think the can says it is good for 20 years. If you could buy a smaller qty then it would be a great find. We used to use 10% chlorine bleach solutions but found this to be better and not as offensive.
I would clean it off with a light bleach and soap.
Then blow dry it off.
And then seal it with zinnser bin, which is a shellac primer. It will seal the wood, and you'll stop looking at that OSB :)

Shellac is a better sealer than Kilz IMHO.
bleach is more dangerous than mold, leave it alone.
Agree with Snipes.

I just read an article on Removing Mold. They also Cautioned on Using Bleach. DON'T!
Hi ADHDan,

You could try this a 1/4 of a teaspoon of oil of clovers in a 1 litre spray bottle.
Just spray a mist of it over the mould or mildew that will kill it. Wait a few days
than wash it off with white vinegar. That is the recipe for all mould & mildew.
I hope that helps. Let me know if it works. That is what I use here in Australia.

Cheers Graham.
Thanks all for the advice. After considering it all I'm leaning towards this plan: spray it down with a non-bleach, non-ammonia mold control spray like this:, let it dry and scrub/repeat per instructions, and keep an eye out for any darkening/spreading patches down the road. If it looks like the problem returns, I'll spray it again, wait and wipe with vinegar, and then paint with oil-based Killz.

Does that sound like a reasonable plan? I have extremely limited time right now so even if the spray just delays the problem for a while (and I eventually have to do a bit more work), that's fine with me.
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