Does it damage a boat leaving it in the water all year?

[Dooglas]

Originally Posted by noelex 77

Polyester fibreglass laminate does experience a significant loss of strength (50%) with long term immersion in water......

Originally Posted by noelex 77

This does not seem to have effected old boats a great deal, but in the early days they were very overbuilt.

You don't find any conflict between these two statements? As the above recommendation is so at odds with common practice of most owners of boats over 25' (excepting those where winter haulout is mandatory), and since "long term immersion in water" is pretty much a way of life for boats - it would seem some specific references would be appropriate.

[john61ct]

In modern times production boats are not designed to be used for many decades.

The more modern engineering / build standards can of course achieve that, but it must be done intentionally and of course costs a lot more.

So many early fiberglass boats hulls are so immortal simply because they did not know how shoddy they could go.

The default is build to a cost / price goal, that's where the engineering advances are directed, maximize profits while only guaranteeing what, 10-20 year reliability?

Saying old boats last longer, just like New England 200-y.o. farmhouses, ignores the vast majority that are long gone, the only examples left for us to see are the overbuilt exceptions.

[noelex 77]

Originally Posted by Dooglas

You don't find any conflict between these two statements? As the above recommendation is so at odds with common practice of most owners of boats over 25' (excepting those where winter haulout is mandatory), and since "long term immersion in water" is pretty much a way of life for boats - it would seem some specific references would be appropriate.

An off season haul out is very common in many parts of the world. Anecdotally, I have noticed the boats given this treatment seem to suffer fewer osmosis problems. The full time cruising boats are affected more, but they also tend to escape to warmer temperatures, so it difficult to seperate these different factors. Of course owners do not do any formal testing of laminate strength, so laboratory studies are needed to evaluate this factor.

My internet connection is poor at the moment so I cannot Google the refrences, but this is an example from the applied science department of Kingston University and is a typical result.

If you can provide the opportunnity for a polyester laminate to dry out it is benifical in my view.

[danielamartindm]

In a word, no. What damages a vessel either in or out of the water is lack of maintenance to address the basic realities that degrade the materials that boats are made of: UV degradation, oxidation of metals, dehydration of rubber goods, and failure to act upon issues when they present themselves.

[a64pilot]

I know composite aircraft surfaces gain weight over time, most common composite is fiberglass, but that can mean many things.
There used to be and may still be a few fiberglass control surfaces on the roof at the Piper plant in Vero Beach, they were up there to asses the long term effects of exposure to UV radiation, but they noticed that as time went on, they gained weight, which as to be moisture, and this on parts never immersed.
I believe there are or were several parts, using different resins, beyond that I don’t know.
I got this info from a Flight test DER that we and Piper used a lot.

[Calif.Ted]

If I told the boatyard here I wanted to haul out for a couple months to dry the boat out they'd question my sanity then remind me they charge $150/day for the limited yard space. There is no "off season" in many parts of the world and no cheap waterfront land for parking boats.
I worry much more when the boat is perched on stands rather than floating.

[john61ct]

On the other hand those with a trailerable boat that have a custom cradle built that properly supports the hull,

have the ability to store it and work on it on their own property with zero ongoing expense when they're unable to be out cruising

"Life is what happens to you while you're busy making other plans."

[Island Time O25]

Talked at length with a boat builder friend of mine specifically on that subject. Briefly his qualifications - born and lived on an island in a small East European country until 14 and dingied to school since 7 years old. At 12 years old joined local youth boat building club, BS and MS in naval architecture, been designing and building under 12m boats for the past 45+ years, about 3 doz designed and 300 boats built altogether.

What he says:
- No fiberglass is 100% impermeable to water. But the permeation rate is so slow that we don't usually see or feel it. But it does get heavier and somewhat waterlogged (ever so minutely but still waterlogged) if in the water 24/7 for a considerable length of time (years? decades?) and without any drying out periods

-If possible, and financially feasible, any boat will benefit from a periodic dry out periods of some sort or another. Just how long and how often will depend on the circumstances, build quality, comptenece of the haul out yard guys etc.

-Sun is more of an enemy of a fiberglass boat then just water. Prolong exposure to both compounds the effect. These are the main reasons why boats staying in the tropics age much quicker than their sisterships in the Northern climes. His rule of thumb is that 3 to 5 years in the North (assuming winter haul outs) are equivalent to 1 full year in the water in the tropics. According to him, other than aesthetics and everything else being equal, a boat which spent 20 years in Great Lakes will have aged considerably less then a boat which spent 7-10 years in the tropics.

-Covering the boat from UV light will do more to reduce the deterioration then just a haul out by itself. Both are ideal to doing either or neither. Covering only while on the water in the tropics is also problematic as without GOOD DRY air circulation it contributes to rot, mold, etc.

On a personal note. When I first looked at my current boat I went over it with this friend as a pre-survey looksee. We pretty much did a real survey. My friend was surprised at the condition of some of the systems and items, most of which looked original (30 years old at the time). It seemed that different items aged differently with some none at all and others looked their age (30 years old). When I went through the boat's papers, reciepts, logs, etc. the bulb went off and the puzzle was solved.

It turned out that the boat spent its first 20-22 years in the Great Lakes with winter haulouts, then 5 to 7 years in Florida on the water, then 3 years in New England on the hard, well covered and ventilated, etc. My friend figured that up to 80% of whatever was wrong with the boat and/or systems was a direct result of its years in Florida. He also surmised that had the boat spent all of its 30 years in Florida it would have been junk by then and not even worth a survey.

Another funny aside. The boat's heater was leaking like a seive when I first tried to use it. Turned out it was plumbed by its Great Lakes owner to take the water from the outside (i.e. fresh). The boat's Florida owner never bothered to replumb it to the tanks and apparently was taking salt water hot showers. Put a new heater in, ran a few gallons of vinegar through all the piping and the problem was solved.

[Jammer]

Originally Posted by boatingnewbie

I'm new to boating and curious about how bad it is or isn't to leave a boat in a slip (in the water) year-round (such as in Florida on the ICW).

Is a boat's hull fine long-term (being kept in the water) as long as it's occasionally cleaned?

Yes as long as the various possible problems are addressed on a regular and ongoing basis. Among these are: possible damage from various aquatic organisms, damage from galvanic corrosion if zincs are not replaced regularly, and the risk of sinking particularly if the boat is unattended.

Originally Posted by a64pilot

It depends on the boat.
I wouldn’t want to leave an inboard / outboard in water

Or, equivalently, a saildrive. At least not without due care and frequent haulouts. And in some waters, not at all. There are harbors on the Mississippi that never freeze where slips are now quite inexpensive. The zebra mussels are here, and they can destroy a stern drive remarkably quickly.

Originally Posted by Rorzech

Second Law of Thermodynamics, All things in the universe are in a state of decay.

Please don't misquote or misapply it. The science is much more specific than that. It applies only to closed systems. Earth is not a closed system, and has decreasing entropy, because the sun heats it on one side at a time.

[14murs14]

Originally Posted by Jammer

The zebra mussels are here, and they can destroy a stern drive remarkably quickly.

Do they eat it? Or are you saying they clog the cooling water intake? In which case I wouldn't call that exactly "destroying" it, just a regular pain to clean it out, no?

[Dooglas]

Originally Posted by 14murs14

Or are you saying they clog the cooling water intake? In which case I wouldn't call that exactly "destroying" it, just a regular pain to clean it out, no?

They don't just clog the cooling water intake, they grow inside all of the water passages. Not so easy to "clean out".

[fstbttms]

Originally Posted by boatingnewbie

I'm new to boating and curious about how bad it is or isn't to leave a boat in a slip (in the water) year-round (such as in Florida on the ICW).

Is a boat's hull fine long-term (being kept in the water) as long as it's occasionally cleaned?

The bottom line is virtually every boat in every marina in temperate climes (and we are talking about millions of boats worldwide) spend their entire lives afloat, only being hauled for relatively short periods for periodic maintenance or emergency repairs.

[Jim Cate]

Originally Posted by fstbttms

The bottom line is virtually every boat in every marina in temperate climes (and we are talking about millions of boats worldwide) spend their entire lives afloat, only being hauled for relatively short periods for periodic maintenance or emergency repairs.

Yep, and they don't seem to dissolve or get prune skin from the life style!

Jim

[Calif.Ted]

Tristan Jones was probably the originator of that yarn about letting a plastic boat dry out.

[Island Time O25]

https://www.sciencedirect.com/scienc...41391015301002

Can any chem engineers here comment on this study?