How to Eliminate Mold from Bilge and Teak & Holly Sole

[erict]

I want to eliminate mold/bacteria growing in the bilge and on the underside of a teak-holly sole. This is in a 30' fiberglass sailboat and good news is there isn't a huge amount of square footage. Also it seems to be a fairly mild case.

In and around the bilge itself there are small reddish stains, presumably bacteria. What cleaners are recommended--preferably ones that are environmentally friendly?

As for the sole, there are small stains in the underside of a couple floor panels. After reading various articles, I am thinking of washing the wood with soap or detergent and then applying polyurethane on the underside and edges. My goal is to clean the wood and then seal it to prevent mold from growing into it again.

1. Will this effectively eliminate the mold and prevent it from coming back?

2. Will applying poly to the underside but not the top cause any problems, for example causing the floor panel to bow?

3. If poly is the way to go, is there any particular product to use or will pretty much anything I find at Home Depot work?

[osirissail]

If you want to rid a boat full of mold, etc. the best way is to go to a hotel supply or service company and rent an Ozone Generator. You have to get the hotel/industrial size machines. Then you seal up the boat, open all interior access doors/panels/etc. and put the Ozone Generator inside the boat along with fans to circulate the output. Run the system for a day or two or more depending upon the output size of the Ozone Generator. The Ozone will kill anything organic in the boat. Then you have to remove the machine and air out the whole boat.
- - Keeping mold, etc. out has to do with keeping excess humidity out of the boat. That can be by having good ventilation or using dehumidifiers or air conditioners if the boat is being stored. Periodic wiping of the walls and surfaces with a disinfectant cleaner helps keep the stuff under control.
- - If the cabin sole panels have dry/wet rot then they need to be replaced. Moisture/humidity will not harm the FRG parts of the boat, but any wood parts will start to rot is they have been "steamed" by having water in the cabin of a sealed boat that is out in the sun.

[Astrid]

You should also make sure the bilge area has its own ventilation system--that is air intake and exhaust vents separate from the cabin ventilation, preferably with intake and exhaust fans built into the vents (can be solar powered.

[PAR]

Fill a squirt bottle with 50% water and 50% bleach. Apply to all patches of mold. Most will dissolve on contact. Scrub, rinse with fresh, clean water, dry with towels, then insure all areas have proper ventilation or you'll have to do this again.

[erict]

I would like to add ventilation for the bilge as well as for the battery locations. How many vents is too many? There is already a solar fan venting the main cabin, although I can't say I really notice the effect. There would be a new one for the bilge. At least one more for the battery compartments (unless they can be tied in with the bilge). Then another if I eventually decide to go with a composting toilet. That seems like a lot of holes in the boat.

[SeaYara]

After two years of living on board we found that the only way to prevent mold is ventilation. We first attack all mold with a spray bottle containing a chlorine solution of 1-5%. Then we clean that with lots of water and let it dry thouroughly.

The best ventilation system seems to be an inline blower put into a tube or duct that starts in your bilge and ends somewhere overboard (in our case in the stern). Make sure the last part of the duct is actually above the through-hull hole, to prevent water ingress. Also make sure you are blowing inside-out. And make sure the blower is spark-free, the bilge is the place where inflammable gasses will accumulate.

When we leave the boat for an extended period in a cold climate, we open up all confined spaces and we put the matresses vertical. When we are on board we specifically air the matresses as well.

Mold fighting in a cold climate seems to be an endless battle. In places like Spain or the Carrib we didn't have trouble with mold, although the tropics might be humid enough. The heat during the day seem to prevent the mold building. But then you need a blower to cool yourself!

[reiner]

white vinegar and water 2 to 1 will do the trick. We got a spray bottle mixed and ready to go in the pantry. Something looks like moulds gets a squirt.
Better for the environment than bleach and works just as well.

[DevoDave]

Look for a clove oil based mould spray. Works a treat and safe to spray anywhere.

[SimonV]

Originally Posted by osirissail

If you want to rid a boat full of mold, etc. the best way is to go to a hotel supply or service company and rent an Ozone Generator. You have to get the hotel/industrial size machines. Then you seal up the boat, open all interior access doors/panels/etc. and put the Ozone Generator inside the boat along with fans to circulate the output. Run the system for a day or two or more depending upon the output size of the Ozone Generator. The Ozone will kill anything organic in the boat. Then you have to remove the machine and air out the whole boat.
- - Keeping mold, etc. out has to do with keeping excess humidity out of the boat. That can be by having good ventilation or using dehumidifiers or air conditioners if the boat is being stored. Periodic wiping of the walls and surfaces with a disinfectant cleaner helps keep the stuff under control.
- - If the cabin sole panels have dry/wet rot then they need to be replaced. Moisture/humidity will not harm the FRG parts of the boat, but any wood parts will start to rot is they have been "steamed" by having water in the cabin of a sealed boat that is out in the sun.

The main mistake when doing a shock treatment is not properly removing or covering all petroleum based products such as carpet, foam, sofa cushions, engine hoses, builge pumps, wireing etc. These items need removing or using Kevlar to cover these items. Kevlar is ozone resistant and will keep the foam or petro chemical base items from interacting with the ozone. Ozone will oxidize foam, rubber and plastics and cause a chemical-ozone smell that can linger for weeks. So do not over do it with an ozone shock treatment! One or two hour shock treatments is advisable. You might have to perform several such shock treatments, but it's better to be safe than sorry when shocking your boat. Some vendors tell their clients to just turn the ozone generator on and let it run for a few days. This is strongly advise against that practice.

[Troubadour52993]

Spray Nine cleaner/disinfectant works well on cloth as well as on the wood and fiberglass, test on finished wood as it may dull the finish. If your bilge is dirty as mine was when I got the boat, it cleans the dirt and stains better than bleach and water as well as taking care of the mold.

Presumably your floorboards are already finished on top, so adding finish on the sides/bottom should be fine. I've used both Minwax Helmsman and Varathane with good success.

Bilge will need to be dry in addition to ventilated to prevent another occurrence!

[osirissail]

Originally Posted by SimonV

The main mistake when doing a shock treatment is not properly removing or covering all petroleum based products such as carpet, foam, sofa cushions, engine hoses, builge pumps, wireing etc. These items need removing or using Kevlar to cover these items. Kevlar is ozone resistant and will keep the foam or petro chemical base items from interacting with the ozone. Ozone will oxidize foam, rubber and plastics and cause a chemical-ozone smell that can linger for weeks. . . .

I have repeatedly Ozone treated my boat over a large number of years that my boat was in storage without any detectable harmful effects to anything inside the boat. I was introduced to the idea of ozone by several hotels I have dealings with. They had large wheeled machines that were placed periodically in rooms to remove all cigarette smoke and other noticeable odors and odors of mildrew or mold. They ran the machines for 8 hours and then it only took a few hours with the windows open to rid the ozone smell from the rooms.
- - I did not want to spray the inside of my boat repeatedly with toxic bug killer sprays and end up with a residue of poisonous chemicals coating the surfaces in the boat. So I opted for the Ozone treatment. These machines are not normally available to the general public as they can be abused and since they kill anything organic you need to be sure animals/pets and other such things are not left in the boat.
- - Where this type of machinery is not available there are "house fumigation" companies that will seal up your boat with plastic and tape and then blow in some serious bug killer fog. After a couple of days of treatment and a few more days of airing out serious "critter" problems are cured.
- - If you are on a dock at a marina or in a boatyard for a long time all sorts of multiple legged critters will find a new home in your boat and getting rid of them with normal household sprays is a continual war that is occasionally lost and then you have to call in the "big guns." In marinas try to avoid any "inside" slips regardless of much more convenient they are. Go for the end of the dock slips if you can. Repeatedly treating your docklines and shorepower cords with bug killer spray helps a lot to keep the invaders down.

[Maggie-K]

You need concrobium mold control/eliminator


Concrobium Mold Control Removes, Eliminates and Prevents Mold and Mould at Home | Concrobium Mold Control

[erict]

Lots of good advice!

I checked on both Concrobium and Spray Nine. Both appear to be non-toxic and very simple to use. The clove oil solution seems to require a bit more work but is also an appealing option.

As others have pointed out, the trick will be ongoing ventilation and keeping the moisture level under control. For now the simplest option is to keep the floor up and leave open the bilge. Since the AC on the boat is trashed, that's my first significant re-fit project. That will allow keeping a small heater running.

There hasn't been any real advocacy for applying polyurethane and I'm content to skip that hassle.