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How much moisture is too much?

Discussion in 'Technical Discussion' started by GFC, Feb 11, 2010.

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  1. GFC

    GFC Senior Member

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    I'm considering the purchase of a 1996 55' boat that has twin 580hp 3406 Cats. The boat had a survey done and I have a copy of the surveyor's report. In it he made these comments about the moisture levels he found--

    Transom: Showing 15% to 20%

    Stringers: From 10% to 12%

    Deck: Reasonably dry displaying 8% to 10% with a little around the deck hardware. All deck hardware would benefit from re-sealing.

    Hull sides: Both sides have elevated moisture below rubrail. The port side displays moisture of 20% for approximately 15-feet aft of the engine room air intakes and the starboard side for approximately 5-feet aft of the air intake. Port side also has moisture around mid-ship thru-hulls.

    Bottom: After being out of the water for 6-hours and readings taken over paint I measured from 15% to 25% and got 7% from the inside. Reoving the paint in a strategic area produced 15%

    Swim platform: Equipped with a power davit causing excessive loads on the platform deck and causing elevated moisture and delamination. Readings exceeded 20%.
    ~~~~~~~~~~~~~~~~~~~~~~~~

    I talked with the surveyor and he said that elevated moisture levels above 23% would mean that water is present and over time this would lead to dry rot. He did not seem too concerned about any of the other moisture levels he found.

    The brokerage has already said they would remove the davit and all mounted hardware from the transom, remove the top of the swim platform and interior wood, then replace it with new marine grade plywood and re-glass the upper surface of the swim platform.

    By way of additional information, his complete survey report consisted of one page. I've had two other surveys done and each report was about 5 pages of information followed by several pages of explanatory material.

    My questions to all of you involve the moisture levels:

    1. Would you be inclined to pass on this boat because of the moisture?
    2. Are there procedures that can be taken to reduce those levels?
    3. Is it going to be very difficult to reseal the deck hardware without having access to the underside of the deck?

    Any information or thoughts/opinions you can share would be appreciated. This is my first venture into a boat this size (I now have a 36'er) and I don't want the purchase to be one I'm sorry about later.

    GFC
  2. Pascal

    Pascal Senior Member

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    a ONE PAGE survey report?
    you said "the boat had a survey done" so i guess it was done by the seller or his broker, which means it's really meaningless.

    what kind of construction? cored? below water line or hull sides and deck only? what kind of core?

    it would help to know what kind of boat your looking at since history would help... ex... if you're talking a cored Sea Ray...

    i think the question is whether or not it's worth getting your own survey, probably if everything else seems ok and you did a sea trial.

    yes, resealing deck hardware is very hard to do unless you can remove the items, which usually means being able to access the nuts underneath.

    personally, I dont' care too much for moisture meter reading espeically on boats that were just hauled out for survey.
  3. BMS

    BMS Senior Member

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    I agree with Pascal the surveyor should not be hired by the seller. The surveyor should always work for you keeping your best intrest in mind. Moisture meters are a great tool but you must remember that boats sit in the water. If you want some good info on surveys and what they should entail and how to interpret them try checking out yacht survey by dave pascoe its pretty informative.
  4. chesapeake46

    chesapeake46 Senior Member

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    In my 20's I fell in love with a F32 Trojan.
    Coming from a 25 ft Searaider, it was like a yacht to me.
    I was an Eastern Shore nudnik.
    I knew alot for my age but was blinded by the boat.
    The boat was in New Jersey, a long drive for me.
    I didn't know anyone there to help me either.
    I relied on the broker to get me a surveyor.
    Big Mistake.
    No details but that boat almost made me quit boating altogether.
    We used to pull up to the marina at night, the headlights from the car shining on the boat and I'd say to my wife in a heavy sigh" I hate that boat"
  5. Henning

    Henning Senior Member

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    Dave Pascoe wrote a good article on this a while back, worth a read.
  6. captainJJ

    captainJJ New Member

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    Moisture in a vessel built in 1966. Yes one should expect this it is quite normal as the emulsion/resin used for bonding the glass reinforced Plastic actually retained moisture. it was purely the gelcoat that formed the waterproof barrier. In northern climes it has been the norm to haul the boat in Autumn and let the air naturally dry out the hull until Spring time. As a rule of thumb 18% is the critical point where one should look to take remedial action by removing the gel coat and preferably hot vac area.

    One has to bear in mind that in 1966 GRP boats were built to the same thickness as wood, they were heavy and contained moisture from day one. It was not until the 80s that one saw the massed produced sail boats where one did not need a light in the hanging locker if there was daylight oustside.

    If the price is right go for it, the broker should have advised you to have your own survey. In Europe the broker will furnish prospective purchaser with a list of local surveyors, it is them up to the purchaser to commision the surveyor.
  7. GFC

    GFC Senior Member

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    JJ, I believe you may have misread my original post. The boat is a 1996, not a 1966.

    I would never rely on the survey done by a surveyor hired by the seller. One must keep in mind first who is paying the surveyor, and second how close is the relationship between the seller and the surveyor. One of the quesstions I asked the surveyor was how often he does surveys for the seller and what was his opinion of the seller. In his defense, the surveyor said that he does 400 surveys a year and has done them for that seller but not often. He also said that the particular salesman I was dealing with over the phone was like a "Used Car Salesman", implying that he would do or say about anything to make a sale. I'm very familiar with their ilk.

    I have a very experienced broker acting as my buyer's agent in this deal, and will definitely hire my own surveyors....one to do the hull and general equipment and a second to do survey the engines and drive lines.

    With the last two boats I bought I used my own surveyor here in the PNW and was very happy with the survey and the report that I received. Unlike the 1-page survey this guy did for the seller, my surveyor gave me a several page report that was accompanied by a several page document explaining many of the terms used in the survey report.

    In each survey it was clear the surveyor was representing me and, at my request, explained much of what he was doing as he surveyed the boat. The results of his reports were used to negotiate with the sellers to lower the costs of the boats to cover the repair costs of the deficiencies identified in the surveys.


    Thanks for the information from each of you, and for the link to David Pasco's article on moisture. Very informative and very well written.

    GFC
  8. captainJJ

    captainJJ New Member

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    oops yes mis read date, however still go with my last comment if the price is right. Re moisture levels.
    Readings need to be taken against bare hull readings taken over antifoul are misleading. You have three options with high moisture readings.
    1. Get boat undercover remove gelcoat, best way is with a gel planer, slurry blasting or similar can be quite evasive and often leaves GRP strands like a choppy sea and wicking. Leave boat to dry naturally, take moisture readings on a regular basis until back to 8-10%. Re Gel with a good epoxy coating.
    2. Same as above however use hot vacumn bagging to draw moisture out, this will be the quickest method and will also bring levels down lower than natural drying.
    3. Not the best way only if moisture is very localised and will only put off further remedial action for a few more years. Scrape back the blistered areas and allow to dry. You could repaint with an epoxy primer however all you will do is retain the moisture.

    So if you have the time go for option 1 however if you buy for the right price go option 2. You should be able to get a quote from a local boatyard for this and consider this in your offer, bearing in mind that it will quite possibly be dryer than when first built.

    Areas where bracing or encapsulation needs to be exposed. Your surveyor would best advise remedial action.
  9. SandEngXp

    SandEngXp New Member

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    Moisture readings

    You will not get an accurate moisture reading over most anti-fouling paints.

    Some gelcoats also contain conductive fillers but rarely white....

    Moisture meters work on electrical conductivity and most bottom paints contain conductive fillers....
  10. GFC

    GFC Senior Member

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    That's a new one on me. So if I'm looking for accurate readings they should be taken from inside the hull?
  11. Henning

    Henning Senior Member

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    That is one way, you can also sand back the bottom paint to base material in several spots especially in areas you can't reach from the inside.
  12. GFC

    GFC Senior Member

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    Thanks for the tips. I should know within a couple of weeks if this deal is going to happen. The boat is on the hard right now and I've asked them to keep it there until after the surveyor gets a chance to take a look at it.

    I'll discuss this issue with him and see what he has to say.
  13. HermanB

    HermanB Guest

    this will be my first post here, so here goes. I don't usually do any posting, I just browse, shake my head and move on. But since I am in the boat repair business, I deal with appraisors, surveyors and ins personel on a regular basis. I find some of them to be very professional and knowledgeable, others, I wonder how they can find paying clients.
    About your moisture readings, first I usually find an area of the vessal that is not usually imersed in the water, take several readings of the area on both sides of the hull, I then take that as my base reading. I then try to take readings on a grid type pattern, and then subract the base reading to come up with a " moisture content reading".
    All fiberglass boats will absorb water into the gelcoat and or laminate, if left in the water for extended periods of time. The longer the hull is imersed, the longer it must stay out of the water to get an accurate reading, 6hrs is nowhere near long enough. Taking readings over antifouling paint, as mentioned earlier, is definatly not acceptable, although I don't think to many owners would be willing to allow someone to peel their bottom just to do a survey, lol. I think you could convince them to allow you take the antifouling paint off in sections, allow the bottom to dry for as long as possible (days at least) then take your readings.

    Hope I do not sound to pompous, but I deal with a lot of misconceptions from both owners and professionals everyday, and this is just one of my pet peeves.

    I will say though, a bit of moisture is no reason to walk away from the boat of your dreams, just negotiate a deal to cover most, if not all the repairs. And as last note, the HotVac system is an excellent way to remove excess moisture from laminate. I know, because I have the only one in Canada, and it works so well, we have 2.

    Thank You.
  14. YachtForums

    YachtForums Administrator

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    Funny. I found myself doing the same thing after reading your post. Could it be your lurking status was compromised by the opportunity to promote your business?

    Do you mean because you usually shake your head at the posts you read on YF? Please accept my apologies Herman. We're just a bunch of uneducated children playing with plastic boats in a bathtub.

    YF has a similar system. It removes unwanted hot-air from the mix.
  15. K1W1

    K1W1 Senior Member

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    Hi,

    Would that happen to be the one and only one in So Fl:

    Complete
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    Letting

    Cheapskate
    Advertising
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    Rubbish
  16. GFC

    GFC Senior Member

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    Again, thanks to each of you for your replies. Last Auguast when the surveyor took the hull moisture measurements the boat had been on the hard for just a few days, and I'm fairly certain he took the measurements through the bottom paint.

    The boat has not been in the water since then and I've asked the yard not to splash it until after my surveyor has completed his checks of the hull.

    The moisture readings were not the only reason I questioned the integrity/ability of the surveyor. His entire survey report consisted of one page. That was my first clue that it likely was not a full blown survey. Clue #2 was that it was paid for by the seller.

    I'm still in negotiations with the seller over many details of the transaction but we're getting closer. If/when we come to terms I'll hire my own surveyor and be very thorough with him about my expectations to make sure we're on the same page. I'll also explain to him about the prior survey results and ask him to pay particular attention to getting good moisture readings. This will be my third survey so I'm a little familiar with what can be accomplished by a good survey.

    Thanks again for all of the tips.

    GFC
  17. Carver370

    Carver370 New Member

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    In regards to your 1 page survey report: It is not uncommon for a Surveyor to conduct a moisture test on a boat for an owner looking to sell. I have friends with Sea Rays who do this almost anually to make sure there are no surprises with moisture on the survey when they sell.

    Was there anything else reported on the survey besides moisture readings? Typically the surveyors around here will only charge a few hundred for the moisture readings if they don't have to go over every system on the entire boat which is why the owners only have them look at that area.

    This wouldn't be a 1995 550 Sea Ray Sedan would it?
  18. H Bolger

    H Bolger New Member

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    I am sorry for you thinking that i was promoting my bussiness, I am up in Canada, I doubt very much that any of your S Fl yachts are going to come to my little town to get any work done. I think you took my post out of context, I am not used to posting on any forums so maybe I did not use proper form, I belong to many sites, my goal is usually to find information that i can use to better our proceedures.

    The only thing that I seen that was possibly out of line was my signature, if that was the problem, why not just edit it out and inform me that it was in contradiction of the rules, which I did read, but did not realize I had crossed the line, again it was not my intention to promote my bussiness.

    No, I meant, I usually shake my head at the so called professional surveyors that give biased unprofessional reports, never mind a one page report. I was mearly mentioning how we did moisture readings. I think if you reread my post it was aimed at the surveyor. That what I meant about " pet peeves"

    Again, I did not mean posts by YF members, i am sure most members would not have been offended, but if any of your members were offened, my apologies.

    Although I do think making the statment " we are just a bunch of ..... in a bathtub" was a bit childish and thin skinned. I am sure your potfolio, and education, are much more substantial than mine, but really, i'm sure with all you're education you could have belittled me with a bit more dignity, for yourself, and still have made your point.

    Again I regret not rereading my post to make certain it could not be taken out of context, my sincere apologies to all of the YF members that I may have possibly offended, unless you are a substandard surveyor, then your probably not on here anyway..........

    Oh and removing me from being able to sign in to rebutt, that was not nessessary, or really was it.......your reading this yes.......

    The referance to the Hotvac System was made by another member, I was just stating how good of a system it is. There are yards in Fl that use it also.

    In closeing, I ask that I be reinstated, but if you really think that I do not belong here, so be it.
    Last edited: Mar 4, 2010
  19. Emerson

    Emerson New Member

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    Fix your formatting so we can tell what is being quoted.
  20. H Bolger

    H Bolger New Member

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    ya sorry bout that, like i said i dont spend a lot of time posting..... i thought it would auto format........