Maintaining a dry, comfortable interior on your boat makes life more comfortable. No one wants to spend their leisure time at sea smoldering in heat, relegated to a hot, sticky pool of sweat and misery. Curbing the moisture keeps passengers cool – and cool-headed.
But the benefits go far beyond personal comfort. Controlling dampness protects your very vessel itself, as moisture is a silent, deadly killer in marine environments. Mildew and dampness can destroy hull structures, wood cores, electronics, and fittings – not to mention mold getting in sails, carpets, furniture, life jackets, and clothing
Using a boat dehumidifier can help. The right unit, along with some simple, best practices, can keep you and your wallet shipshape for years to come.
What’s the point of having a dehumidifier on a boat? Do they even work?
Dehumidifier units like the DryGenie™ protect your boat. Proper moisture removal, dehumidification, keeps your boat dry and in good working condition and maintains a comfortable cabin.
With the DryGenie™, you can maintain constant, ideal humidity — commonly around 50% relative humidity (RH) — so your boat is protected from mold, mildew, and damage. Even when your boat is up on the lifts or in storage, marine dehumidifiers can draw out excess moisture and keep the boat in tip-top condition.
Combatting excess moisture
Excess water and moisture are a part of boating, but it’s important to manage and minimize humidity in the interior cabin and engine room.
Major OEM boat builders are now using the DryGenie™ to prevent costly moisture-related problems such as rotting interior structures, corrosion of metal components, mold and mildew growth, osmotic blistering (hull damage), and engine room delamination.
Other hazards of high humidity include excessive condensation and fogging on windows, hatches, and surfaces, for increased fall risks, poor air quality, and degraded performance of safety gear like life vests, ropes, and lines.
Long-term storage during periods of inactivity magnifies the damage.
Can I use a regular home dehumidifier on my boat?
Yes, but with caution — and some caveats. Home units are designed to air condition interior spaces on dry land; they are not built to handle extreme marine temperature fluctuations, salt-water air, or excessive humidity levels at sea.
Additionally, many are quite bulky and heavy, making them impractical for boats where you are trying to maximize every inch of living space.
Features to look for in a dehumidifier for your boat:
Performance
Robust, continuous performance is a must. Small desiccant humidifiers like Star Brite NO Damp Dehumidifier Bucket use crystals or pellets to absorb excess moisture, but customer reviews suggest it will only last 3—4 months in high-humidity areas like Florida.
Direct Drainage
Able to continuously drain into your sink, shower, or the bilge (lowest point in boat where water collects) so you don’t have to haul and empty water pans. This is extremely important when your boat is in storage or otherwise unattended.
Lightweight
Is it light enough to lift with one hand? Bulky, heavy objects are awkward to install or move on a boat.
Compact Size
Look for a unit that’s small enough to set on a galley counter or in the sink. You want plenty of storage options, so you are not giving up floor space.
Stability
A boat dehumidifier should be able to securely mount to flat surfaces. The DryGenie™ has powerful, suction cup feet that keep it in place amid challenging conditions.
Continuous Power
Power often cycles off on boats. Look for a dehumidifier with an auto-restart or LastState feature. With LastState, the dehumidifier remembers and resets your last settings after any power loss, ideal for when your boat is in storage over long periods of time.
Enhanced Safety for Sea
A marine dehumidifier should be responsive to its environment. ElectroSea’s DryGenie™ has an IntelliTilt feature. This means your unit will shut down if it’s tipped over. This prevents water from leaking out and flooding your interior space.
What are signs you need a dehumidifier?
There are many telltale signs that you may need a dehumidification system for your boat. Signs to look out for include:
- Musty or damp smells inside of lockers, cabin rooms, or bilges.
- Visible condensation (water droplets) on hull plating, windows, or bulkhead.
- Doors or cabinetry materials (wood, foam, fiberglass) swelling or warping.
- Electronics not working. High humidity speeds up corrosion and device malfunctioning
- A wet bilge or other areas where excess moisture or water keeps recurring.
When you spot these signs, it’s time to act. A dehumidifier and improved ventilation can save you thousands of dollars — or more — in damage.
Using a moisture reader like a hygrometer is another indicator your boat could benefit from dehumidification.
According to a study by the American Bureau of Shipping (ABS), ships should maintain a humidity range of 30—70%. Marine coatings manufacturers suggest a tighter range, advising boat operators to target relative humidity (RH) levels of 40—60%.
