# stain over mildew?



## maddawg308 (Aug 29, 2011)

I have some pine boards stored outside, under a tarp, for a few months. There is some moisture which got underneath the tarp and put some light mildew stains on the wood. Not bad, just a little. I want to make some benches out of the wood, and I want to stain them. I know if I was painting the wood, a little Kilz primer would take care of the problem, no harm done. But with staining, was hoping I could just stain over the mildew stains and they would be taken care of. I don't have a pressure washer, a planer, or any heavy-duty tools yet, and the way the mildew has grown on the pine actually makes it look better, so I don't want to remove it if I can help it, I just don't want it growing any more.

Opinions?


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## crank49 (Apr 7, 2010)

Add mildewcide to the stain. HD sells it, I'm sure others must also.

Or if not compatable or possible, you may have to scrub with Borax and let dry. Then stain.


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## BobM001 (Jan 8, 2012)

Get some dry ice. Then with HEAVY insulated gloves place a chunk on the effected area. That will kill the mildew and you can sand out the stain it may have left. Dry ice in a blown stream is how they remediate mold and mildew on wood surfaces in a house.

Bob


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## Grandpa (Jan 28, 2011)

The Mildewcide product is what I would do. They sell it at our local lumber yard and I have used it. It worked well with paint. Stopped the mildew when used as instructed. Much easier than dry ice and probably cheaper too. Safer also. I am not condemning the dry ice method. I am saying Mildewcide is cheap and easy as well as safe.


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## madts (Dec 30, 2011)

You could try using wood beach. I have had good luck with that.


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## crank49 (Apr 7, 2010)

I thought the reason they use dry ice in remedial cleaning was for its abrasive texture when solid and nothing to clean up after it evaporates. Not due to the temperature. Also, I have read that you could kill mildew with high temperature, but I never heard of killing it with freezing. Have i just been living under a rock, or are these documented facts?


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## a1Jim (Aug 9, 2008)

House hold bleach mixed 50/50 with water will get the job done . It my take more than one application. Afterwords make sure you neutralize the bleach with one tablespoon of baking soda to a quart of water and wipe the whole surface down. after it's completely dry wipe down with naphtha and your ready for some blotch control and stain or dye.


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## lumberdustjohn (Sep 24, 2009)

On face surfaces, I have had success by resanding.


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## Grandpa (Jan 28, 2011)

a1Jim, I work with Disaster Relief and we clean up behind hurricanes and floods among other things. They tell us that 10% bleach is all that is needed. They claim that making the solution stronger is just using bleach and not doing anymore. I am not a scientist but the man that gave the talk was so i have to believe him. Don't know but I would do that.


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## maddawg308 (Aug 29, 2011)

Thanks for all the advice, guys. I'll try bleach/water and see what happens.


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## a1Jim (Aug 9, 2008)

Hey Cliff
I've used the 50/50 solution and know it works if 10% works that's great. If for some reason it didn't work maddawg could always make it stronger or do repeated applications. Thanks for the info.


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## Grandpa (Jan 28, 2011)

I am sure the 50/50 solution would work. Bleach is not expensive so you don't save much but it is easier to work with at 10%. I had a chance to buy some wood once that has water stains on it. They said brush it with some sand paper and go on. After a little of that I found that I could stain over the water stain and it looked fine. It was presanded lumber core ash they we were building cabinets with at the time.


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## a1Jim (Aug 9, 2008)

I was wondering is the person that recommended the 10% dilution was thinking of raw wood or painted surfaces?
I've had much different experiences trying to stain over water stained wood ,but it makes a big difference as to what kind of wood and the color and type of stain.
Something else that should be addressed is even using household bleach it can lighten your wood. So on woods like walnut or most dark woods I would try naphtha first and if it's a rust stain your dealing with Oxlic acid to remove the stain. It's also very important never to use more than one type of bleach to clean wood with out neutralizing the previous bleach and letting it dry completely before applying another type of bleach. If you do mix bleaches you can create a deadly gas.


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