Moisture Meter for Boats: Do They Work?

If you’re in the market for a used boat, you want to ensure you’re getting the best value for your money. This means checking the condition of the boat, including the moisture levels in the hull, using a moisture meter for boats.

The trouble is that most moisture meters are developed for industries outside the boat trade, such as home building. As such, most are calibrated to check for moisture in the wood. And most boats today are made of fiberglass—not timber.

Read on to learn whether a boat moisture meter is a valuable tool when testing the condition of used vessels.

Cons of a Moisture Meter for Boats

In many cases, the readings given out by moisture meters are unreliable for boat condition surveys. They are highly sensitive instruments that read more than just dampness.

They Can Be Too Sensitive

Testing boat moisture is a crucial part of boat maintenance. Moisture infiltration can be insidious, destroying the condition of a hull from the inside out. And despite its outward appearance, fiberglass isn’t immune to moisture.

However, when it comes to boats, moisture meters can be too sensitive. Any slight bump or simply placing them on an uneven surface can give unreliable readings. This is especially the case with analog meters.

The Meter Might Be Reading Other Substances

If you’re learning how to test boat humidity, the readings from a moisture meter can easily confuse you. This is because they detect contaminants other than water in hull substrates. For example, hygroscopic salts like chlorides can cause a meter to return a positive result, even when no moisture is present.

However, a reading of zero can be relied upon. This always means the hull or other area you’re testing is dry.

Pros of a Moisture Meter for Boats

Despite their limitations, moisture meters are still helpful in the marine industry. Surveyors and boat owners can use them successfully to get an overarching picture of the condition of a hull.

You Don’t Need to Destroy Anything to Get a Reading

One of the key advantages of a moisture meter is that there’s no need to extract any of the material you want to test. The device is simply placed on a surface to get an internal reading. Of course, the accuracy of the reading depends on how powerful the device’s probes or electrodes are and how well they make contact with the material.

If you’re worried about moisture in the interiors of your vessel, consider purchasing boat dehumidifier packs like this.

They’re Useful When Measuring Dryness

In many cases, it’s better to rely on a moisture meter to test dryness rather than moisture on a boat. That’s because, as we addressed above, a meter that returns a dry (or low moisture percentage) reading is more accurate than a moist reading.

This is important when, for example, you’re planning to re-coat a hull surface or determining whether deck coring is damp.

It’s Not So Clear Cut

So what’s the bottom line? If you’re buying a used ocean or lake vessel, having a moisture meter for boats isn’t essential—but it still might give you some insight into the condition of the hull. If you’re unsure whether the boat you’re buying is right for you, employ the services of a marine surveyor to test every aspect of its condition before sinking your hard-earned cash into it.

For more tips and tricks to make your on-water experience the best possible, read the other boating articles on our website.

Moisture Meter for Boats: Do They Work?
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