War on drips
On our boat, Silom, moisture typically formed in the lockers behind the settee cushions, in the corners of the headliner above the V-berth and along the hull in the cabinets under both the head and galley sinks. It goes without saying, Silom is not insulated.
The worst place moisture formed was between the mattress in the V-berth and hull liner. Eventually stains from black mould (mold to our American friends) appeared on the supposedly mould-resistant coating on the bottom of the mattress.
Years of wiping down those surfaces with solutions of various recipes and strengths — vinegar, bleach, concrobium — didn’t seem to rid Silom of mould, at least not to the degree that would make me happy.
Until this year.
This fall I initiated a series of preventative measures that seem to have worked over the winter. Here’s what the Condensation Cop (that’s me) has done:
- Every time I light the propane stove, or boil the electric kettle, I put up a small, powerful 12-volt
fan in the porthole above the galley stove. I fasten it there with a thin bungie cord, and turn it on to blow warm, moist air outside the boat. It also has Velcro so you can hang it elsewhere if you need to. I purchased it a few years ago at svhotwire.com, but I don’t see it on their website any longer. It would be easy to fashion something similar.
- I insulated the metal
seacocks/pipes under the sink in the head to stop condensation forming and dripping along the hull. I also put a small 25-watt light in there to keep it bright and warm, and so far, no mould has formed for the first year ever.
- I bought a dozen small dollar-store screw top plastic containers and drilled three or four holes in each cap. I filled them with a squirt of Kanberra Gel from the large 24 oz. bag, saving a lot of money over buying multiple small containers of it. I put them in all the lockers and in nooks and crannies where the air doesn’t move as much as in open spaces. It really seems to work as very little or no mould has formed.
- I leave a fan on at the foot of the V-berth to keep the air circulating better, and put hydra-vent all around the mattress where it presses up against the hull liner.
We have a regular house-sized Bionaire dehumidifier under the salon table. If I don’t have the Dickenson Newport heater on, which dries the air nicely, I have it running, and pull out 4-5 litres of water every few days, depending on the weather. - A Dri-Z-Air water catcher is placed in the hanging locker and emptied of water every few days. The moisture-absorbant crystals are replaced regularly.
- My biggest project was painstakingly removing the wooden slats and hull liner board from beside the V-Berth. We insulated the space behind with spray foam, replacing the board and covering it with a hull blanket liner before remounting the slats. This has made a huge difference as virtually no moisture has formed here, which was one of the worst places before.
- We don’t shower on the boat. We are lucky to have a membership in a lovely gym/pool close by with shower facilities. Even if we didn’t have that luxury, I would always use the marina facilities to keep all that humidity out of the boat.
- I open up the ports and hatches every chance I get during dry weather, and monitor the humidity level carefully. If it gets up to around 50% I do what I can to stop it from going any higher.
That’s it. It’s a war we seem to be winning. I would love to hear from others who have had success against condensation and the tricks they have used.
Your battle against condensation is not unique! Those fans, as you use in your galley window, can be cheaply purchased at computer repair stores, new and/or used, for between $1 and $20. If you cut the corners off, and attach them using a standard kitchen cupboard hinge, the 3 inch ones fit inside of a 4 inch cowl vent (we have one over the galley, one in the head.). The 5 inch ones move a lot of air, quietly, and we have one mounted behind the diesel heater chimney and one near the floor (they draw <1/4 amp and cured the problems of moisture in the affected areas in the cabin). Others circulate air in the V and 1/4 berths.
For insulation, we used 1/2 inch sheet styrofoam, with a membrane surface, from Home Depot.
Coupled with a Dickinson, Alaska diesel heater, our boat is warm and dry, year 'round.
An unbelievable difference in comfort
That’s a great idea to put one in the cowl vent, but wondering if you have it blowing warm wet air out or fresh air in??? Thanks for you suggestions. Keeping dry makes all the difference doesn’t it?
Both blowing out. The one in the galley takes care of the propane moisture and that emitted by any cooking.
The head is situated just opposite the diesel heater so I added a hold open hook, to the head door, which allows for airflow from the heater to exit via the head and then the cowl vent when drying out our wet weather gear.