Drying out...

imac8

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Over the weekend a few boat owners I've spoken to have said they've taken their boat out of the water during the winter to 'dry out' as well as routine maintenance. When quizzed they said it's because it's something they've always done.

Do modern GRP hulls really need to dry out?
 
I don't understand the logic behind this and I have only ever taken my boat out of the water for anti fouling, can someone shed any light as to why, You very rarely see very big fibreglass boats out of the water for the winter period?
 
OAF

In my case the reason is that, having a 44-year old boat, I usually need to do a fair amount of maintenance and repairs each year. Also I usually undertake some major project (eg installing a new gas locker) that requires electrical power and a stable working platform, together with parking nearby for a car loaded with tools and materials.

I prefer to get this work out of the way during the winter, thereby leaving me free to enjoy my sailing when the days are longer and the weather is warmer.

Does that strike you as illogical?
 
I have always spent 4-8 weeks ashore every other year. Only because I thought that was best for the boat. I prefer winter months in the water and then a bit of time ashore to 'dry out' or 'air' whilst we were off on holidays. I asked the question about boats in the Med recently and it sound slike no one bothers down there so I would say given teh number of boats there it probally not needed,
 
A topic which comes up every year without fail.
Living where I do,we watch the local yacht clubs haul out their fleets each year until very spare inch of hard standing has a sailing boat parked on it,leaving all the trots empty.
Sometime around spring the entire process is reversed.
The local motor boat clubs totaly ignore this convention and their boats remain resolutely afloat,only being taking out for essential mending and antifouling.
Can only assume that raggies are much more weather sensitive and that their annual mantaince is much more comprehensive and takes far longer to carry out.
As to the drying out,raggies appear to be convinced that "drying out " is a vital part of stopping your boat falling apart whereas most stinkpotters simply do not understand the concept.
In many years of boating have never ever even thought about coming ashore to dry out a hull even though 100% of my boats would have been those ancient heaps slapped together using all those prehistoric resins which were supposed to positively encourage osmosis,wicking and delamination.
Curious, it seems those with the most modern composite materials in their boats are most paranoid about osmosis.
So much for progress eh :)
 
We've thought about and asked this question before and this year for the first time, we will be leaving her in over winter. She doesn't need antifouling so we will have her lifted early spring just for a scrub and a check over then straight back in. Why waste the glorious winter days we seem to be having? That's my view anyway. :)
L
 
My understanding is that the GRP hull, is not totally impervious to water, and will absorb some over time. It is therefore sensible to lift out for a least a couple of months every 2-3 years. Racing raggies might choose to do this as often as possible to minimise any increase in weight.
 
the Italian surveyor on my boat, Gino Ciriaci, is a experiences (retired) specialist /engineer in boat hulls, He has written several articles in Italian magazines about osmosis and boat hull treatment, and he used to do inspections for gouvernment, navy, ...

he adviced me that:

wooden boat huls MUST stay in the water to keep the hull in good shape,

GRP boat hull, its best to take her out each year for a few months, to let the hull dry out, ....avoid osmosis, get the moisture out of these microscopic holes, ...

thats GC's opinion
 
the Italian surveyor on my boat, Gino Ciriaci, is a experiences (retired) specialist /engineer in boat hulls, He has written several articles in Italian magazines about osmosis and boat hull treatment, and he used to do inspections for gouvernment, navy, ...

he adviced me that:

wooden boat huls MUST stay in the water to keep the hull in good shape,

GRP boat hull, its best to take her out each year for a few months, to let the hull dry out, ....avoid osmosis, get the moisture out of these microscopic holes, ...

thats GC's opinion

A view shared by me and born out of a few decades of listening to my dad & other peeps far more knowledgeable than I.

The most recently clarification of this belief that GRP boats absorb moisture was with a friend who had totally ignored my advice to get his boat out the water every year over winter who was trying to sell his little used 2005 Bayliner 285. It had been in the water (on the Thames) for 2 years without a lift out, the previous lift out had only been very brief scrub off, antifoul & re-launch. He had an offer subject to survey so boat was lifted & survey done & buyer pulled out as moisture reading "too high". My friend spoke to the surveyor and was told that the boat had simply been in the water too long without a lift out and time to dry out. All he needed to do was to leave it out the water to dry out for at least 5 months & if he wanted he would return to do another moisture reading. He duly did this and the reading was dramatically reduced back down to "normal" levels. As it happened the buyer had not found anything else so in fact then went ahead... what a happy little story :):):rolleyes:

..as someone has said, this is a discussion point every 12 months or so...
 
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In my area, South Florida, most boats stay in the water year round; however, it is generally acknowledged that keeping the boat out of the water as much as possible is best for the boat in the long term for several reasons; in our area one of the common ways to get the boat out of the water is to install a boat lift at one's own home, some of the benefits:
- Saves the need for frequent antifouling, painting or cleaning the hull
- Keeps the boat clean of barnacles and marine growth ( big savings in labor )
- Once docked in the lift, no more fenders are needed and no more banging or rubbing other boats
- When on the lift there is improved security especially during hurricane season ( I spent one night during a particularly wet hurricane bailing my old center console boat because the bilge pump couldn't handle the amount of water that was coming down and the boat was about to sink!)
- No more worries about bilge pumps failing when you are away
- usually Increases the value of the boat when selling if it has been stored on a boat lift
- Fuel consumption and speed of the boat will be increased with a clean hull and the reduced weight achieved by not have anti fouling
- Less corrosion of galvanic anodes and especially of your boat's metal surfaces.

I am in the process of installing a lift in my home for the above mentioned reasons.....
 
My friend spoke to the surveyor and was told that the boat had simple been in the water too long without a lift out and time to dry out.

GC has been measuring moisture on my boat hull also,
and told met that a boat that is just lift out (or the day before) alway's shows too much moisture,
he told me that these measurements are useless, but he nevertheless did them, just for him, to have more measurements / experience (?) over time,
or perhaps to make the broker and the customer feel good :)
 
We've thought about and asked this question before and this year for the first time, we will be leaving her in over winter. She doesn't need antifouling so we will have her lifted early spring just for a scrub and a check over then straight back in. Why waste the glorious winter days we seem to be having? That's my view anyway. :)
L

hi lisa......FAR BE IT FOR ME TO OFFER ADVICE, when not requested, BUT, as you say you will just give boat a "quick scrub in the spring", can i recomend you use the sealift (no connection) in cowes. they will do all that in about an hour !!! JOB DONE!!! better that hoist n chock etc ... this year it was about £100 for the hour all in !!! it would,nt hurt to book well in advance either...............well, that what i would do for what its worth !
 
hi lisa......FAR BE IT FOR ME TO OFFER ADVICE, when not requested, BUT, as you say you will just give boat a "quick scrub in the spring", can i recomend you use the sealift (no connection) in cowes. they will do all that in about an hour !!! JOB DONE!!! better that hoist n chock etc ... this year it was about £100 for the hour all in !!! it would,nt hurt to book well in advance either...............well, that what i would do for what its worth !

Ta steve. Good idea. I love your ideas and I miss your vids so roll on summer :):)
L
 
As I wrote before, I lift my boat out every winter mainly to make it easier to work on her but I also think letting the hull dry out each year is a good thing

Her previous owner left her afloat all year. After a couple of years being owned by me I had to extend the boot topping downwards because she was lighter, and floated higher out of the water, showing an unsightly band of red antifoul.

The difference was not due to me carrying less gear because he raced her successfully and did not cruise far, but I only cruise and carry a load of spare gear, tools, larger anchors, 70 metres of chain etc. which he didn't.

GRP hulls do let water through. If they didn't there would be no such thing as osmosis.
 
Over the weekend a few boat owners I've spoken to have said they've taken their boat out of the water during the winter to 'dry out' as well as routine maintenance. When quizzed they said it's because it's something they've always done.

Do modern GRP hulls really need to dry out?

I purchased a 1988 GRP boat last year and she has only ever come out of the water to be antifouled. As a result I found she has one or two very small spots where water has got into the hull. So this winter she's been lifted out, all the old antifoul has been removed (at great cost) and I joke not when I say that there seem to be about 25 layers of the stuff on her ! She is now going to sit in a shed until the Spring so that the bare gelcoat has a real chance to properly dry out, then she will be epoxy treated and re-antifouled.... hopefully good for another 10 years or maybe more, andpossibly a knot or two faster as a result of losing all that old antifoul !
 
The most recently clarification of this belief that GRP boats absorb moisture was with a friend who had totally ignored my advice to get his boat out the water every year over winter who was trying to sell his little used 2005 Bayliner 285. It had been in the water (on the Thames) for 2 years without a lift out, the previous lift out had only been very brief scrub off, antifoul & re-launch. He had an offer subject to survey so boat was lifted & survey done & buyer pulled out as moisture reading "too high". My friend spoke to the surveyor and was told that the boat had simply been in the water too long without a lift out and time to dry out. All he needed to do was to leave it out the water to dry out for at least 5 months & if he wanted he would return to do another moisture reading. He duly did this and the reading was dramatically reduced back down to "normal" levels. As it happened the buyer had not found anything else so in fact then went ahead... what a happy little story :):):rolleyes:...

So the boat had been left in for years and had a high moisture reading, but it had done no damage to the hull, and it could anyway be "resolved" by leaving the boat out of the water for a few weeks. That surely suggests you don't need to take the boat out of the water, rather than proving that you do?

Actually, more precisely it suggests that you should take your boat out of the water a few weeks before selling it, because a surveyor can't determine whether a hull with high moisture content is a problem or not, until it has dried out, so best to dry it out and remove the ambiguity.
 
Over the weekend a few boat owners I've spoken to have said they've taken their boat out of the water during the winter to 'dry out' as well as routine maintenance. When quizzed they said it's because it's something they've always done.

Do modern GRP hulls really need to dry out?

No its worse being out in the winter.
Best advice is ignore moisture readings and osmosis, its just for surveyors/boat yards to make money.
 
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It is widely recognised and understood that drying the boat for six weeks a year will reduce the onset of Osmosis.

Recognised by whom? The longest I have had a boat out the water is a week - well I used to in my early days of boating take the boat out at the end of the ""season, but that was my loss until I realised there was no such thing as a season. And any commercial operator will tell you pretty much the same.

The last boat I shared as a school boat was of 1986 vintage and was in the water all year round apart from a week each year and a couple of sea lifts. No problems with the hull at all.
 
I have a 15 year old Hardy which I had surveyed before I bought it. No osmosis present, but in his report the surveyor advised that the boat should be "stored ashore each winter to allow the hull to dry out, and thus extend its life". I find that it's a good opportunity to clean and re-antifoul, plus it allows some time to do maintenance or make improvements. Lifted last Friday, and will probably go back in early March.
 
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