Mold \ mōld \

According to Merriam-Webster, mold is “a superficial often woolly growth produced especially on damp or decaying organic matter or on living organisms by a fungus”

According to sailors, mold is as synonymous with boating as is fun and adventure.

Because boats are in the water almost all the time, and very near water when hauled out for maintenance or storage, they are almost always in extremely humid environments, and the number one thing mold requires for growth, is moisture.

Our first experience with mold on the boat was a couple years ago when we found ourselves in Wilmington, North Carolina in the late fall. Outdoor temperatures were cool enough at night to require us to turn on the heat: warm, moist air inside, cool air outside, resulting in condensation on the inside of windows and the inside surfaces of the hull.

After a couple weeks of being there, one day Anna Marie went into one of the closest and what did she find? Lots of mold! We emptied all the closets, washed all the contents as well as the walls of the closets, and started hanging closet dehumidifying bags in them all, to try to keep the moisture levels down. I purchased a few combination temperature/hygrometer units, and spread them around the boat to keep an eye on humidity levels. After a couple weeks, we moved to warmer climates where the indoor/outdoor temperatures are similar, and condensation is not much of an issue.

Because that cleaning was such a labor intensive event, we kept a close lookout for signs of mold, added some room dehumidifying desiccant bins, and became very militant about making sure the boat stayed as dry as possible. This includes checking the closet bags frequently to make sure they are changed when spent, ditto for the room desiccators, and always making sure salt doesn’t make it’s way to the interior of the boat by showering after a swim, keeping the decks and cockpit washed regularly, and wiping your feet thoroughly when traveling from above deck to below. This is extremely important as salt attracts water and it is much easier to prevent salt from getting below, than it is to clean it up afterwards.

This regimen served us well for a couple years until recently. Because our haul out in Virginia kept us there until late December, and our stay here in Georgia lasted through January and February, the boat has spent the last four or five months in a climate whereby we needed to utilize heat at night and often during the day as well. Although we were doing a good job keeping the humidity levels down, when the difference between the indoor temperature and the outdoor temperature are on the order of 30 or 40 degrees Fahrenheit, you are going to get condensation inside, and with condensation you are going to get mold, and we did.

At first, I noticed it on a section of fabric we have lining the berth walls of the forward cabin. This area was stained when we first took ownership. When we were in Grenada, we had a professional carpet cleaner come aboard with his steam cleaner, and he did a great job with this fabric. Subsequently, when we noticed it needed cleaning again, we hired someone when in New York. He was unable to get the stains out, and the brushing action of his equipment was causing the material to shed fibers, so we didn’t push him. Instead, we sprayed the material with a mild bleach solution to make sure everything was dead, and resolved ourselves to live with the stains. We also made plans to remove and replace this material as soon as we could figure out exactly how this could be accomplished.

Here we are in Georgia, and I’m looking at this fabric and saying to myself, “that looks a lot worse than it was”. I started spraying different areas with different products to see if anything worked to remove the old stains or the new ones – it didn’t. About this time I had to retrieve some filters stored in one of the cubbies in the forward cabin. When I reached inside, I noticed the plastic bags were wet – yes, wet! When I took them out and looked inside, I couldn’t believe how much mold there was on the carpet that lines this cubby. I started looking around the boat in hidden areas close to the hull, and came to realize we had a lot of work ahead of us. Cleaning the non-porous surfaces would not be difficult at all, but the fabric areas and the affected carpet was a different story.

This is the fabric lining the forward starboard berth wall. The lighter colored areas are normally exposed to light. The blotch in the center is a wet area treated with a non-impressive product.
Forward cubby where the filters were located

I started researching the problem extensively. Some of the best articles I read were from Practical Sailor. The article entitled “Fighting Mildew, Mold, and Lichen” was very informative, and the links in that article to other articles were all helpful and educational.

After reading almost all the articles Practical Sailor had on the subject, I decided to give their “Formula B (2 tbsp of Baking Soda; 2 tbsp of Borax; and 1 tbsp Trisodium Phosphate)” a try. It did show some visual results on the carpet lining the cubby, but near to zero change on the fabric. The problem was time. It took 12 to 24 hours to start to see any noticeable change where it was working. In the meantime, I tried other products and home remedies on various test surfaces, but nothing was working as I wanted it to. The practical sailor articles often said “don’t expect miracles…” or language similar. I wanted a miracle!

Just a sampling of some of the products I tried. Formula B is in the bottle to the left, the one in the middle is a 3M product to prevent future growth.

For the fabric and carpet areas, I needed something that was going to work quickly or this project was going to last too long . One website I found indicated that the best product for carpets was Tilex®. What? A high bleach content cleaner on fabric or carpet? I was skeptical.

My research indicated these synthetic materials should not be harmed and should retain their color if the dyes were colorfast. I tested a small area of the fabric on the starboard berth wall, and it worked miraculously. Even though I am not a fan of using harsh chemicals, this was one job whereby I was willing to change my ways.

I literally just sprayed the product on, and watched the majority of the stains disappear before my eyes. Some of the older stains required a second application, but that was it. I attacked one area per day, keeping the cabin well ventilated, and after about 24 hours, did a second application and waited another 24 hours for the area to dry.

Fabric lining the forward starboard berth wall AFTER treatment with Tilex®
Forward filter cubby AFTER treatment with Tilex®

The Tilex® worked even better on the carpeted liner material. Again, it was just spay and wait. I was able to use less product and the results were impressive.

Aft section of Forward Port Berth Locker BEFORE treatment with Tilex®
Aft section Forward Port Berth Locker AFTER treatment with Tilex®

There are a slew of cabinets and drawers on both sides of the interior of our boat. Many of them have light yellowish stains, primarily on the back wall, on the carpet. Before we purchased the RK, I was told by someone-in-the-know showing me another Amel that had similar stains (from memory), that these were from the adhesive used to install the carpet. When we originally took ownership, we tried to get these out using various detergents and scrubbing to no avail, and assumed it was the adhesive. Maybe the boat we looked at did indeed have carpet mastic stains, but on our boat most of these are old mold stains that have yellowed with time. The Tilex® is making them disappear and I hope to have them all gone within another couple weeks.

One of the Forward Starboard Cabinets BEFORE treatment with Tilex®
Same Cabinet AFTER treatment with Tilex®

So far, after about 4 or 5 weeks of this, we have completed the forward port and starboard berth walls, captains berth wall, the lockers under the forward and aft berths, all 4 closets, about half of the 50+ cabinets and cubbies, as well as all the contents thereof. We have also taken the opportunity to do a good deal of organizing some of our stuff into plastic storage containers. When we are all done, she will look like new.

Morning Anna Marie. Time to go to work!
Captain Paul in action!
Pile of books from one of the many cubbies on board
To be on the safe side, everything was cleaned before going back into the clean cabinets, cubbies, and closets
This is the underside of one of our Sette cushions. This sits on top of one of the freezer chests and is usually cooler than the ambient air – conditions for condensation.
Same cushion after treating with Formula B, waiting about 48 hours, and then cleaning with vinegar. It didn’t come out perfect, but I know what remains is dead. We plan to have this item and a few others that we didn’t bleach attacked by a professional steam cleaner
Time-lapse video of carpet treatment with Tilex®. This was captured over approximately 10 minutes.

To prevent future problems, we have donated or thrown out a bunch of closet items and clothes to allow more airflow in the closets. We took items we rarely use and stored them in vacuum bags after cleaning or laundering (including rarely worn closet clothes). Items we use regularly that seem to have an affinity for growth have been sprayed with Formula B, 3m Marine Mildew Block, or Goldshield GS75 Surface Antimicrobial Agent. We will see which products work the best. Going forward, when we are in climates requiring use of the heat, we will be much more vigilant about checking the closets for condensation and looking for early signs of growth in some of the inconspicuous locations in an effort to catch it quickly. We plan on making this the last time we literally clean almost every surface and most items from stem to stern as a single condensed project.

Living on a boat is a constant learning process. You read, you listen to others, you think you have a pretty good handle on things, and then you wake up one morning and realize you don’t know much at all. But mother nature has a wonderful way of forcing us to learn.

It is a lot of work to live on a boat, but who could complain when this is what you see when you come up for air

Should any of our readers have knowledge they can share, please notify me or better yet, post a comment. I would love to add additional useful content and experience to this post.

6 responses to “Mold \ mōld \”

  1. Wow! I need to bookmark this the next time we get mold in our bathroom. Also: Would love to hook you up with some more books next time I see ya!

    • Thank you Lisa. I hope your bathroom stays mold free!

      As for books, please send me the titles. I’m taking advantage of my digital library card. The mold doesn’t seem to grow on the iPad!

      Anna Marie

  2. Hey sorry to hear about your mold infestation. Nanny used vinegar on everything and I have found that white vinegar works wonders on mold and mildew. I see you mentioned it and from what I have researched it is supposed to be better than bleach hoping the Tilex solution works long term for you. You are both becoming experts in the most interesting situations. Good job and keep enjoying those views. Joanne

    • We use vinegar on the boat for a lot of different things – I love the stuff. It is great at killing the mold but not very good at breaking down the cell structure of the organism or removing the stain. Our experience has been that if treated with the ‘Formula B’ (FB) first and letting that sit for at least 48 hours, the vinegar will then actually help get rid of the stain. On some fabrics we have had to do this 2 or 3 times to get it perfect. Apparently the FB will both kill and break down the cell structure and the longer it sits there the better. It has been very helpful in areas that we can spray and just let sit for a while. I’m hoping I don’t need to utilize this knowledge anytime soon. We are going to do our best to stay away from the colder climates. Love you.

  3. Love this “Living on a boat is a constant learning process. You read, you listen to others, you think you have a pretty good handle on things, and then you wake up one morning and realize you don’t know much at all. But mother nature has a wonderful way of forcing us to learn.” That’s living.

    Send you and Anna Marie lots of love and wishes for your well-being and safe travels.


    • So good to hear from you Kelly and thanks for your comment! Lots of love to you and Martin as well.

      Paul and Anna Marie

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