Killing mold for good?

[Bigjim]

My boat was on the hard for years. She's been back in the water for two years now. She had lots of water intrusion and I've fixed many of the leaks, but she's still pretty wet.

The issue that just arose is mold. I thought I had it licked last year. I washed off all the mold on all exposed surfaces and had a fan running through the summer which kept it gone.

But now it's winter and she's back on the hard and not plugged in. So, I can't run fan full time anymore. I don't have solar installed yet so the interior is pretty stagnant. I went on board the other day and, even though it's below 30 degrees, lots of the exposed surfaces have that mold again.

First, what cleaner do you recommend using to get rid of the mold that doesn't present other problems or health risks?

Second, is there a product I can use to treat the surfaces to keep it from coming back?

[sailormed]

Look at ozone generators, they seem to work without consuming to much power. I have no personal experience.

[gonesail]

there is a boat sized dehumidifier that also generates ozone .. if you have shore power in the summer. they will not work in less than 50 degrees. you can drain these into the sink. mold does not like low humidity.

[letsgetsailing3]

People didn't read the part about not being hooked up to power. If you had power, I'd suggest a dehumidifier.

Add a solar fan.

You need air circulation.

[Mariano]

Use 1/2 part of water, 1/4 bleach and 1/4 of a goog quality detegent to rinse everything , even wood. That mix will not only clean , but also kill mold

[tkeithlu]

Bleach kills. Nothing survives it, so that's your route to removing the objectionable stuff. We use this little dehumidifer, drained into a sink, when the boat is closed up with no one working in it. It would not keep up with a person's exhaled water vapor, but sealed up, it covers a a 44x10 foot interior. It can run on 12v DC or 120v AC.

https://www.amazon.com/Pro-Breeze-El...s%2C210&sr=8-5

[CarlF]

Use this home made cleaner that tested best by Practical Sailor. Clean off the mold with it then wipe a bit more on and let it dry. The residual will retard mold coming back. The ingredients have no smell, don't stain and are all used in food products.

1 quart hot water
1 tablespoon baking soda (sodium bicarbonate)
2 tablespoons washing soda (sodium carbonate)
2 tablespoons trisodium phosphate (TSP)

But you also have to get some air movement. It doesn't take much. Get a small solar panel (10w) and just tie it to the deck. Put a computer fan in a dorade vent or a port that rain doesn't come in with tape. You don't need a controller - just hook it up directly. These Noctua fans are great and use less than 1 watt of power. It works better to use the fan to exhaust air.

https://www.amazon.com/Noctua-NF-P14...7Z5H4HY2B6TC8T

[nightowle]

As property manager and boater I recommend Concrobium. It quickly and effectively removes mold in a single treatment and it does so without any noxious fumes or vapors. This product can be applied in a number of different ways including a spray bottle, sponge or fog sprayer. It's fairly mild and not dangerous to use.

Be careful using an ozone device; read up on them. They can affect electronics and cause more problems than they are worth.

[JPA Cate]

@BigJim:

Mold spores are throughout the world. New ones arrive to set up shop on your boat. So, however you kill them, that's only those ones. It is an ongoing battle.

I haven't tried this myself, so take it with a grain of salt, as it were. I have a friend whose boat lives in a moist climate, who swears by using 8 drops of clove oil to 1 liter of water, mix in spray bottle, and spray affected areas. She claims the solution penetrates porous surfaces where mold spores hide, and that it gives some protection against re-currence. The sticky point for me is that I know there are more spores out there, and I find it hard to believe the clove oil will retain its effectiveness (if it really has any at all.) I will try this if I get desperate mold-wise.

Ann

PS You can get clove oil at pharmacies, it is used to rub on little kids' gums when they're teething, to relieve pain.

[osprey877]

I use “Dri Z Air” dehumidifying crystals. RV’s swear by them. No power required and as long as you regularly empty the water they collect, they will definitely lower the humidity in your boat.

[Chotu]

As someone who is very allergic to mold, I can help you out a lot. LOL

First, there are places on your boat that you probably can’t get to that have mold growing. Not too big a deal, I’m sure you are more concerned with the stuff you can see. But behind any wooden panel there is the potential for mold if it is near the hull.

The main thing you need to do is get more ventilation. You need air flowing through that hull all the time. Obviously it’s winter where you are now, so dehumidifiers aren’t really going to be doing anything. Plus you don’t have power. See if you can find a way to open the thing up but rig it so no water gets in. I don’t know what that means for your specific boat, but get the air moving through the boat. Open up the bilges, and let the air blow through everywhere.

As for cleaning up the mold, good old fashion scrubbing. That’s the best way to do it. But use a sponge and water that is full of borax. Leave a film of borax on any place that you don’t want to see mold grow again. I’m assuming it’s not in a cosmetic area. If it is a cosmetic area, maybe you need to refinish that area with something shiny and slippery so the mold is easy to wipe off.

If you leave a film of Borax anywhere in the boat, mold will never go there again.

I will contradict some other posts and say that bleach does not work. It bleach is the mold, makes it color less, but the mold survives. It comes back. Borax is poison for the mold and it won’t let it grow any more.

You may have some luck with ozone for removing mold behind paneling you cannot reach, but that would be an ongoing thing. You’ll have to keep doing it. The Borax is permanent. Until it gets wet again.

[Lodesman]

I've used Thinwater's mix and found it very effective: Sail Delmarva: Mildew Treatment for Pennies

[Bigjim]

Originally Posted by Chotu

As someone who is very allergic to mold, I can help you out a lot. LOL

First, there are places on your boat that you probably can’t get to that have mold growing. Not too big a deal, I’m sure you are more concerned with the stuff you can see. But behind any wooden panel there is the potential for mold if it is near the hull.

The main thing you need to do is get more ventilation. You need air flowing through that hull all the time. Obviously it’s winter where you are now, so dehumidifiers aren’t really going to be doing anything. Plus you don’t have power. See if you can find a way to open the thing up but rig it so no water gets in. I don’t know what that means for your specific boat, but get the air moving through the boat. Open up the bilges, and let the air blow through everywhere.

As for cleaning up the mold, good old fashion scrubbing. That’s the best way to do it. But use a sponge and water that is full of borax. Leave a film of borax on any place that you don’t want to see mold grow again. I’m assuming it’s not in a cosmetic area. If it is a cosmetic area, maybe you need to refinish that area with something shiny and slippery so the mold is easy to wipe off.

If you leave a film of Borax anywhere in the boat, mold will never go there again.

I will contradict some other posts and say that bleach does not work. It bleach is the mold, makes it color less, but the mold survives. It comes back. Borax is poison for the mold and it won’t let it grow any more.

You may have some luck with ozone for removing mold behind paneling you cannot reach, but that would be an ongoing thing. You’ll have to keep doing it. The Borax is permanent. Until it gets wet again.

Yes, borax has been a long time staple for cleaning. Sometimes old fashioned works best.

I've been working on getting various means for air circulation. It's tough in the winter. I didn't think I'd have to worry about mold in the winter!

Thanks

[a64pilot]

Originally Posted by nightowle

As property manager and boater I recommend Concrobium. It quickly and effectively removes mold in a single treatment and it does so without any noxious fumes or vapors. This product can be applied in a number of different ways including a spray bottle, sponge or fog sprayer. It's fairly mild and not dangerous to use.

Be careful using an ozone device; read up on them. They can affect electronics and cause more problems than they are worth.

I second the call for concorbian, nothing else I Have ever used really worked to keep it gone, even bleach won’t really kill mold, but the Concorbian does.
Now I believe it’s active ingredient is actually sodium carbonate, it also has TSP in it, but I believe that’s to make it a good cleaner, and the sodium carbonate AKA soda ash or washing soda is what kills the mold spores.

I say that as I believe the home brew quoted by another may well work, but Concorbian isn’t expensive so I just buy it, best place to buy it is Home Depot or Lowe’s if your US based.


But bleach or vinegar really doesn’t do it, bleach may bleach it out so you don’t see it, but it doesn’t kill the spores so it’s coming back, and I’d guess vinegar covers up the smell.

Concorbian has come into its own for people that have had their houses flooded, that’s when mold really, really becomes an issue, you rip the dry wall and insulation out but the mold is in the studs, so if you use a garden sprayer with beach to spray the studs down and then rebuild, the mold comes back, with Concorbian it doesn’t.

The Concorbian has no smell, isn’t greasy and leaves no residue, and hasn’t harmed anything we have used it on, but by all means test first before you spray down that expensive upholstery.
https://www.concrobium.com/products/mold-control-spray/

[thinwater]

a. The formula for Concrobium is given in post 7. It's based on an old patent. You can mix this up yourself for pennies.


b. The Borax variation (link in post 12) is MUCH more effective on boats. Don't change the concentration and leave the film to dry.


c. Bleach will kill it, but as we all know, bleach neutralizes itself within a few hours. It will not prevent the return because there is no chlorine residual.


d. Vinegar can kill it if enough is there. But mold likes low pH (vinegar) and vinegar becomes mold food (it will actually make it grow faster in some situations). I've tested this.


e. Algae and moss elimination formulas sold for pools , roofs, and decks can also be very effective. There are several chemistries.