Mold

[davefromoregon]

I live in Portland Oregon. It rains a lot here. It is relatively temperate as well, so boats get a lot of mold on them.

I power washed to boat yesterday and am fairly certain there was more mold growing within an hour of power washing.

Is this just the way it will be until it gets dry mid summer?

[pesarsten]

I use a diluted mix of liquid pool chlorine and water with a scrub brush. Bleach kills the mold and helps to keep it gone. Keep anything like lines out of the bleach and rise well.

[UNCIVILIZED]

Caution! Bleach eats Kevlar, Twaron, & other aramids. Along with some sail cloths, cloth resins, rope coatings, etc.

[nknowland]

Vinegar. Your new best friend.

[thinwater]

I did a lot of testing to a number of magazine articles, including bleach, vinegar, and many commercial preparations. The most effective general purpose product for killing, removal, and prevention is the DIY formulation, below. Basically a more effective variation on Concrobium, the key ingredient, borax, is a very effective antimicrobial. Leave the last coating in place for prevention. Do NOT over concentrate. Also VERY effective inside on carpet. For cleaning + prevention, nothing comes close. No odor, no bleaching effect.

Sail Delmarva: Mildew Treatment for Pennies

If the problem is actually black algae or lichens (more likely on-deck, since mildew requires dark--they look alike and are often confused) another good answer is BAC (benzylalkonium chloride), available cheaply as pool algae treatment. Dilute about 100:1. Additionally, it is not good for a marine environment, so strictly limit run-off. In fact, it is best to lightly wet the surfaces in dry weather and not rinse it off. It will kill the algae and prevent the return. Very effective on canvas, in addition to applying a water repellent (dry canvas doesn't grow stuff).

Elite Marine Shield and Gold Shield are silane based alkonium chlorides that are even more effective on synthetic fabrics. Good for prevention on Sunbrella etc.

All of this was described in Practical Sailor Magazine, and below in "Keeping a Cruising Boat for Peanuts."

[zeehag]

vinegar and tarps. keep water out and off... open slightly the now covered hatches for ventilation, which is your other new best friend.

[Cheechako]

Exterior mold should be controllable with pressure wash once or twice a year. But Zeehag is right on! cover up and ventilate!

[davefromoregon]

This is all exterior mold. I have had no issue with interior mold.

[sapient sue]

nknowland said vinegar is your best friend - he neglected to say it should be white vinegar. This ia a cheap product which I put it in a spray bottle - spray the effected area and scrub with a nail brush - works well even if you do smell like a fish and chip shop for a while. Ventilation is the key. We used it all the time we sailed in the Pacific North West and we are still using it here in Aussie.

[zeehag]

Originally Posted by davefromoregon

This is all exterior mold. I have had no issue with interior mold.

there is probably also algae in with that topsides mold-- tarping with ventilation--keep tarp about a foot or so above the deck so air can get in and throuhgh. .
the mold and algae grow in oxidized gelcoat.
you might wish to buff it out and WAX it to prepvent the discolorations and fuzzycritters growing on your oxidized gelcoat.
enjoy the work. it is kinda fun.

[Painted Skies]

The best mold-busting and mildew-preventing product we've found over the years is Wet & Forget. It is a product that is marketed for use on concrete, siding, roofing and outdoor furniture to remove any growth and then keep it away. The version we use comes as a concentrate that can be applied using a spray bottle or garden sprayer - the stuff is a miracle IMO. You don't even have to remove the mold or mildew before you use it, and each time it rains the stuff is reactivated into action.

We used to have a serious mildew issue on our v-berth headliner; I assume because of the condensation caused by our breathing throughout the night (heaven forbid!). Four years ago, I cleaned the crop of black fuzz away and sprayed the area with Wet & Forget. It has never returned. I also use it after I clean the shower enclosure - along the bottom edge of the shower curtain and inside the shower sump to prevent any mildew and mold from forming. It has also been well-utilized on the underside of the Sunbrella bimini and dodger once a year. I haven't found it to cause any adverse effects on gelcoat, varnish, or canvas but I do make sure to immediately wash any off of the Strataglass.

We have only ever used the original 'outdoor' formulation of Wet & Forget, although I notice they now have special versions including one for interior use. Beware that the stuff should only be applied in well-ventilated spaces; breathing it is not recommended. In the US, you'll find it at Lowe's or Costco. Here in Australia, we've bought it at Costco but also seen it at some Mitre 10 stores. Easy to find a store by searching worldwide at this link:

Wet & Forget Store Locator | Find A Store Near You With Wet & Forget

Cheers, Katherine

[Arthur Garfield]

I use an ozone generator to terminate mold entirely.Use when away from boat or when on hard.Open everything to bilges.Run it from shore power or solar if you have it.Turn it on close all hatches and let it run for a few days-no mold.
Now don't be breathing to much and air out cabin before use.

All the Best

[thinwater]

Originally Posted by Painted Skies

The best mold-busting and mildew-preventing product we've found over the years is Wet & Forget. It is a product that is marketed for use on concrete, siding, roofing and outdoor furniture to remove any growth and then keep it away. The version we use comes as a concentrate that can be applied using a spray bottle or garden sprayer - the stuff is a miracle IMO. You don't even have to remove the mold or mildew before you use it, and each time it rains the stuff is reactivated into action.

We used to have a serious mildew issue on our v-berth headliner; I assume because of the condensation caused by our breathing throughout the night (heaven forbid!). Four years ago, I cleaned the crop of black fuzz away and sprayed the area with Wet & Forget. It has never returned. I also use it after I clean the shower enclosure - along the bottom edge of the shower curtain and inside the shower sump to prevent any mildew and mold from forming. It has also been well-utilized on the underside of the Sunbrella bimini and dodger once a year. I haven't found it to cause any adverse effects on gelcoat, varnish, or canvas but I do make sure to immediately wash any off of the Strataglass.

We have only ever used the original 'outdoor' formulation of Wet & Forget, although I notice they now have special versions including one for interior use. Beware that the stuff should only be applied in well-ventilated spaces; breathing it is not recommended. In the US, you'll find it at Lowe's or Costco. Here in Australia, we've bought it at Costco but also seen it at some Mitre 10 stores. Easy to find a store by searching worldwide at this link:

Wet & Forget Store Locator | Find A Store Near You With Wet & Forget

Cheers, Katherine

The pool algae treatment has exactly the same chemistry for 1/3 the price. I have tested both. Pool algae treatment from Walmart is the deal.

The difference is the concentration (6:1 for Wet and Forget, 100:1 for Clorax Algae Eliminator). Pool chemicals are more concentrated and have a lower mark-up. And that is why I do product research.



https://www.walmart.com/ip/Clorox-Po...&wl13=&veh=sem

[Celestialsailor]

There have been some great threads on mold. You may want to do a search for that. A suggestion I learned from there and put into practical use was clove oil mixed with water and a vinegar bleach. I did it every few years and I have never seen mold again. Makes the interior smell like a dentist office though. I'm sure it wold work on the exterior.