osmosis prevention

P

paulburn

Well-Known Member
Joined
2 Apr 2006
Messages
117
Visit site
I have been recently told that I should epoxy my hull (Beneteau 27.7 and 3 years old) as protection against future osmosis. There is no current problem. I was wondering if this is standard practice and how much might I expect to pay.
 
I would imagine that telling you is current practice.
You'll get a whole range of answers on this. It's just sorting out what is the best advice that is tricky.
My six pennorth is that if you wait until a bit of osmosis is present the job won't cost you any more and will put off the expenditure, perhaps for ever!
Most people agree that osmosis in itself is not a problem, but selling a boat with it can be.
 
"My six pennorth is that if you wait until a bit of osmosis is present the job won't cost you any more "

i am afraid i have to disagree with you on that one.

far better prevention than cure (and cheaper)
 
Dunno about "Standard Practice", but if you intend to keep the boat for more than a couple more years I WOULD do it both as a preventative measure and so I could tell any future buyer that it had had it done as a preventative measure (and show him the photos & invoices).

IMO Osmosis is vastly more damaging to a boats VALUE, than it is to the actual boat.........so the more you can do to avoid it the better and IMO with 2 identical boats for sale, one with a preventive coat of epoxy and one without, then I would go for the one with Epoxy..........but opinions do vary and their is a cost to weigh up..............
 
But that assumes that it is inevitable. Why pay a fair old wack to prevent something that may not happen.
Insurance companies con us like that all time.
 
yep agree with that, but if you do the work yourself like i did it only cost 400 quid on a 27 footer which is not to bad
 
But have you tried applying epoxy/osmo protection with uk weather?

You really need to get the boat inside, around 15c, steady.

It's always hit and miss unless you do it in summer, spring is to damp, well now it is > we had frost this morning!
 
Curious advice on such a new boat.

Awareness of osmosis has led to newer boats having more "water penetration resistant (isophthalic?)" resins used in the lay-up process.

If you're afloat all year there may be some sense to the advice but, if you winter ashore then it gives the hull some "drying-out" time.
 
Paul - who told you this?

Was it a survey? - in that case you will have (in your fist) the readouts from the electrical penetration survey! (the inherent retained moisture)

Do you have any significant hull deterioration (Bubbles?) they are noticable - have you actually seen any?

Do you have any noticeable areas of delamination or severe (i.e. penetrating) perforations into the hull caused by impact damage?

We all know that Ma Beneteau makes hulls thinner than a chickens egg on a starvation diet - but they do tend to stay afloat longer than 3 years - probably due to the amount of Sikaflex 692 that holds the damned thing together - (I am obviously not a great fan of the Ma Bene stable - but then I have had to work on them - and they are frighteningly bad)

However badly they build the boats - Ma Beneteau would not have been in the position to dictate the Europran Small Craft Directive had their boats been subject to congenital sinking due to osmosis.

If your boat had been 30 years old - I would not expect to see it above the waterline. However it is not 30 years old.

Rest assured - if you have been given no certificated knowledge of osmosis - then none such significantly exists - if you have observed no such indications then no such osmosis exists.

Osmosis only causes a proplem when small (Damaged) areas are left untreated for a significant time - then water ingresses and spreads itself around.

Molecular water ingress has not been a problem for the last 15 to 20 years due to the gelcoats compounds - this has nothing to do with who makes the boat and everything to do with who makes the compound that Ma Bene et al use as the gelcoat and base material.

Tell your 'adviser' to go and "boil his head" - ignorance is bliss - untill it eminates from the mouth.

If you 'see' osmosis then deal with the areas concerned - do not leave to get worse - until that day - enjoy your sailing

regards

brian
 
many thanks. I wondered whether if I had the epoxy treatment then the boat would never get osmosis, whereas if I didn't have the treatment then it might get osmosis. Peace of mind. Not sure if it's as clear cut as that ?
 
expoy treatments, or even full osmosis treatments (where they strip the gel coat completely, perhaps relaminate and replace a new waterproof barrier, and dry for a long time) dont come with a guarantee (at least not more than a few short years) as far as I understand.... that says something in itself.

If the boat has a high moisture content (especially if there are blisters), then an epoxy barrier can also cause problems by sealing it in.

So, you take your chances. If the boat is dry (ask a surveyor to check with a moisture meter), and an epoxy treatment is within your budget without hurting, and the boat's not been epoxied from new (some are) then why not.... I'd be tempted. But dont 'expect' it to work, it mightn't.
 
No. I still don't get it.
Pay money to have a treatment, which in itself would raise suspicions in a buyer, to prevent something happening that may well not happen.

House surveyors went from one "favourite" dire problem to another Rising damp - Susbsidence - Foundation slab chlorination - and God knows what now. During each period the mortgage providers would insist on remedial work. When the next favourite emerged the last one was quietly forgotten.

Save your money.
 
My advice to you Paul (a) never put it near water.
(b) Sell it.
Then buy a house on a cliff edge, as you obviously
need something to worry about
Hope this advice is useful to you, if not worry why
its not Cheers Tony
 
From one of David Pascoes articles...[ QUOTE ]
Unfortunately, our research reveals that the blistering of boat bottoms continues to be a growing source of complaints and lawsuits against surveyors. It seems to be one of those pernicious problems that just won't go away. In fact, the number of lawsuits against surveyors has actually increased dramatically in the last several years.

[/ QUOTE ]
So they would recommend remedial work before the fact then wouldn't they. Especially as it takes the liability away from them.
[ QUOTE ]
Remember that a client who seems unconcerned about blisters at the time he is purchasing a boat that has them, may develop other ideas later on. If he decides to sell a short time later, and is faced with a $6,000 repair bill, its pretty obvious what is likely to happen if the surveyor hasn't adequately covered himself.

[/ QUOTE ]

There are some interesting articles on the site, but don't forget which side of the fence he is on.
 
With a relatively new boat you don't have much antifoul to scrape off so its relatively easy to do the work.

If its relatively easy to scrape back to a bare gelccoat then I'd do it and buy one of the coal tar epoxies for oil rigs - they're only about #50 for a 2.5 litre two pack and paint on by hand on nice warm summers day, the following day move the hull supports and do anither coat, the third day the same.

Should keep the boat blemish free for a couple of decades IMHO

But whatever you do don't sand off the existing gelcoat a light abrasion with 400 grade to dull the surface and provide a good key is all you should need.

But really you should not need to do it at all, I'd spend the money on beer!

Fair winds

Ken
 
Paul,

Yes, do it. I've a ten year old Nauticat which was epoxied when new. I've scraped the hull back to the epoxy this winter and I've just had her moisture tested to see what the moisture content is currently. The readings were extremely good - only marginally more moist than a brand new hull. Having scraped back to the epoxy - and slightly marked the epoxy in the process - I am now applying another prophylactic coat of International's Gelshield 200 to continue the protection.

rob
 
You must log in or register to reply here.

Share this page

Top