I've always been a big proponent of boat owners, and more importantly boat buyers, owning a moisture meter. I don't suggest this because I want every DIY boater to think they are a surveyor, or to try and circumvent the surveying process, that is not my point at all. I suggest it because in all seriousness the meter above paid for its self the first time I used it to rule out just one boat. Essentially, a survey for 30+ footer can run $600.00 or more these days and whether or not the boat passes you pay the surveyor the $600.00+.
More often than not you find a boat and it looks great on paper and on Yachtworld.com. You then meet the broker, bring your spouse and you both get an extreme case of boat buyers lust. "She's just perfect!" Your heart gets racing and you begin to imagine how much fun it will be to own her. But wait a minute, she looks great on the surface but what's underneath? Is she in need of hidden big $$$ repairs?
Any good and reputable broker should offer to bring along a moisture meter, if not just ask. Sadly though many less helpful or thorough brokers claim they don't have one or don't know how to use one. More often than not they don't actually own one. This to me is like going to a family practice doc who does not own a stethoscope. If this is the case ... well.. your choice? I know many good brokers, who have meters, and who go over the deck and cored hull before even listing a boat. Ask all the questions! If you don't ask them, you won't get any answers.
So what can you do to protect your self from paying for surveys on boats with saturated decks or hull core? Buy an Electrophysics CT-33, or its sister meter the J.R. Overseas GRP-33, read this blog and the manual, do a Google search of "moisture meters for fiberglass" and then go for it.
When we bought our current boat I looked at over 50 boats, meter in hand. It did not take me long to rule many of them out due to severe moisture issues. Many times I would not even involve the broker and instead would do a drive by, find a ladder, and at least circle the chain plates and deck fittings near the rail. I don't suggest boarding any boat without a broker, I didn't just leaned the ladder up and did some cursory checking, I have been able to rule out many boats this way without wasting a brokers time. Heck on many "drive by's" I never even had to get out of the car! I saw some nice boats and some basket cases but unfortunately some had some really hidden deck problems even though they were in good cosmetic condition.
The CT-33 is sold by Electrophysics in Canada currently sells for $160.00 and you'll need a calibration block for another $10.00. The US distributor, J.R. Overseas, has an exclusive deal for all US sales and they sell a meter that is slightly altered, has different scale graphics but that is essentially a very similar meter. The J.R. Overseas GRP-33 sells for $325.00. I use the CT-33..
Electrophysics Inc. (LINK)
The photo above shows the first thing to do when you turn it on. Simply flip it on and hold it vertically in mid air. The needle should read zero. This is an initial calibrations check.
Please DO NOT buy a moisture meter if your intent is to circumvent the survey process! To master the use of one takes time and should be used with soundings, something many DIY's don't have the ear for. Using one to rule in boats that may be a good candidate for a survey or to rule out boats that have a pegged meter all over is fine and can save you money.