Trying get rid of Musty smell with DIY Borax Formula and maybe bilge paint?

[Carl Wonderful]

Got a Catalina 22 (1971) but actually in really good shape for its age. It has a bit of a musty smell (not terrible but definitely noticeable) even after taking all cushions and everything out and airing out with a fan for months. I want to do a lot of weekend trips and sleep in her a lot but worried cause I get really sick when I'm around mold. I just got new cushions and I have vent fans and will have as much air circulating as possible of course.


Got 3 Main questions...

1. Anyone have experience with the Borax cleaning formula (Borax, Baking soda, TSP, water...)
1 quart hot water
2 tablespoons baking soda (sodium bicarbonate)
2 tablespoons borax (sodium borate)
1 tablespoon TSP (trisodium phosphate)

People seem to swear by it as a very effective cleaner/killer for mold/mildew (and preventer) and I guess its way less toxic too. Seems too good to be true but..? We cleaned and scrubbed all day in lockers & bilge areas with the Borax formulas...so used that solution and went wild brushing/cleaning with it on every inch of all inside locker areas and bilge areas that we could possibly get to. Hoping this will get rid of the musty smell..?

1a. This seems to work great but leaves a white film everywhere. Its my understanding that its also a preventative for mold/mildew if you sort of leave it on and not totally wipe it all off? Not sure. Am I doing it right? I definitely want to prevent mold mildew from coming back.

2. I was also considering painting most of these areas with rustoleum oil enamel to really seal it and make it harder and less likely to get mold/mildew. I know there's bilge paint and expensive marine paints for this but I like to try to keep it simple and try stay on a budget if I can.
-Any experience with rustoleum in lockers and bilge?
-Heard of adding a hardener to ...(harden...help make more durable and to prevent mold??) but cant find one that seems compatible.

3. How to tell if its mold or mildew? I cant tell. Is there a huge difference between the two or any easy way to tell them apart? The lockers have what looks like mold spots here and there (some parts more concentrated) that sort of became part of the (fiberglass). Most did come off with the borax solution though. Most is dark colored which makes me think mold...but doesn't have really much "body" to it and doesn't really come off when touched with finger. So maybe just old mildew that's not really even alive still? Health concerns? Will my cleaning and painting do the trick?

Any help would be super appreciated to help me understand all this and to keep myself as healthy on my boat as possible!!

 

[dlochner]

There are a couple of variations of that formula, it works well. @thinwater is the person who best answer your questions.

 

[mforum]

We’ve had a ‘86 Catalina 27 for last 7 years. It had been sitting a lot and had a mold/mildew problem when we got it.
There’s a lot of good info on the forum if you search for it.

What I have used/found the most beneficial in controlling the mold/mildew problem since we have had our boat is:
1. Constant air flow/ventilation. Someone somewhere on the forum wrote to the effect, it should be like a hurricane in side your boat. I use a small fan on an on/off timer with the v-birth cushions propped/covers open, the engine compartment door open and stern locker hatch propped open just enough to get air flow through the whole boat but not water in through the hatch.
2. mold resistant mildew/pain to hard to get areas that typically I don’t clean, e.g. under fuel tank/v-birth under cushions/settee lockers. I used zinsser perma-white antimildew paint from Lowe’s. See this article from Practical Sailor: Anti-Mildew Weapons - Practical Sailor
3. Cleaning hard surfaces with warm water/bleach/murphy’s wood soap solution every 3-6 months. I rinse off the eating surface areas (galley counter/table) with water.
4. For the cushions, I used a small amount borax dissolved in warm water; just enough to saturate top surface but not completely soak the foam. Then used a shop vacuum to remove and dry. My understanding is borax dissolved in warm water is safe (you can wash baby clothes it it) but you don’t want to breath the stuff if aerosolized from the powder.

As to the mold versus mildew question, I’ll leave that to my immune system‘s white blood cells to figure that out. As my gray hair emerges, I’m coming to understand that my brain is probably the dumbest organ in my body. I don’t think we can’t eradicate/or prevent all microorganisms from living just like we do, nor should we want to. The science suggests even human lungs have a small microbiome of bacteria and funguses. https://en.wikipedia.org/wiki/Lung_microbiota

I generally think my air quality when sailing with a mildewy boat has still been better than the last 15+ years commuting to work on an interstate behind 40 000 other tailpipes.

 

[BAD ORCA]

Mold will still grow on bilge paint. I used it in my head on the wood frame for my holding tank, and some black color mold did grow on it. It was easier to wipe off with some windex, but the paint may only help by giving you a smoother surface that is easier to clean. It might help get rid of some of the old funk though so may be still worth the effort.

 

[rgranger]

I’ve done this on a MacGregor 22. It’s a bit of a pain, but it works. Remove anything you don’t want damaged, then go inside with a pressure washer in one hand and a shop vac in the other. Add some Pine-Sol to the washer’s soap reservoir and clean everything thoroughly, then follow up with a fresh‑water rinse.

Next, set up a few fans and let the boat dry for several days. After that, close it up and run an ozone generator inside for a few more days (an example is available from Home Depot).

At that point, the boat will smell great—and honestly, that’s where I should have stopped—but I went one step further and painted all exposed fiberglass surfaces with…




The boat smelled VERY fresh ... even three years later when I sold it.

 

[thinwater]

Got a Catalina 22 (1971) but actually in really good shape for its age. It has a bit of a musty smell (not terrible but definitely noticeable) even after taking all cushions and everything out and airing out with a fan for months. I want to do a lot of weekend trips and sleep in her a lot but worried cause I get really sick when I'm around mold. I just got new cushions and I have vent fans and will have as much air circulating as possible of course.


Got 3 Main questions...

1. Anyone have experience with the Borax cleaning formula (Borax, Baking soda, TSP, water...)
1 quart hot water
2 tablespoons baking soda (sodium bicarbonate)
2 tablespoons borax (sodium borate)
1 tablespoon TSP (trisodium phosphate)

People seem to swear by it as a very effective cleaner/killer for mold/mildew (and preventer) and I guess its way less toxic too. Seems too good to be true but..? We cleaned and scrubbed all day in lockers & bilge areas with the Borax formulas...so used that solution and went wild brushing/cleaning with it on every inch of all inside locker areas and bilge areas that we could possibly get to. Hoping this will get rid of the musty smell..?

1a. This seems to work great but leaves a white film everywhere. Its my understanding that its also a preventative for mold/mildew if you sort of leave it on and not totally wipe it all off? Not sure. Am I doing it right? I definitely want to prevent mold mildew from coming back.

2. I was also considering painting most of these areas with rustoleum oil enamel to really seal it and make it harder and less likely to get mold/mildew. I know there's bilge paint and expensive marine paints for this but I like to try to keep it simple and try stay on a budget if I can.
-Any experience with rustoleum in lockers and bilge?
-Heard of adding a hardener to ...(harden...help make more durable and to prevent mold??) but cant find one that seems compatible.

3. How to tell if its mold or mildew? I cant tell. Is there a huge difference between the two or any easy way to tell them apart? The lockers have what looks like mold spots here and there (some parts more concentrated) that sort of became part of the (fiberglass). Most did come off with the borax solution though. Most is dark colored which makes me think mold...but doesn't have really much "body" to it and doesn't really come off when touched with finger. So maybe just old mildew that's not really even alive still? Health concerns? Will my cleaning and painting do the trick?

Any help would be super appreciated to help me understand all this and to keep myself as healthy on my boat as possible!!

Yes, that will kill the mold/mildew (they are both fungi and are closely related), but unless the residue can remain, the mold will return, if the conditions are right. Thus, it works well on upholstery, but not so much in the bilge.

I do use it in the bilge as a cleaner. Economical, effective, and crawling in a bilge with bleach is basically not safe. The problem is, it's water-soluble and will wash off if the bilge is constantly wet. Still, it is often effective for several years.

The first solution is to dry the bilge. Ventilation and fix the leaks. My last boat had a dusty bilge. No mold. My Corsair, not so much. Additionally, few boat ventilation systems are set up to actively draw air from the bilge and out. They focus on the cabin and that's it. Ideally, all of the ventilation air should be exhausted from the bilge, not hatch ventilators. That will also prevent you from breathing air that has been in contact with the bilge. I've been tempted to install a solar ventilator in my cockpit, where it would draw from the bilge, but I've been lazy. If you have a problem with mold, DO THIS.

Small dehumidifiers are also very good. Petlier effect, the a big compressor type.

Anti-mildew paint additives can help. The simplest is to add some Wet-and-Forget to water-based paints. It's about 10% benzalkonium chloride (BAC), which is quite effective at about 0.05%. (You need about 2 ounces per gallon) It can also be sprayed on the walls; it does not wash off as easily as borax. Do not use it as a cleaner; it isn't and if you rinse out a lot, it is a moderate marine toxin. Dilute as directed and just a very light spray.

There more durable treatments. Goldshield GS5 has to be scrubbed off, and can withstand condensation for a few years. It can also be used other places in the cabin. I've tested it. Good stuff. I should probably buy more. They have other products. Similar to BAC but it last longer.