Barnacles, bottom paint and related boat care

[Daveinet]

Having never owned or been around a boat that way stored in the water, I know nothing about bottom paint and general care of the bottom of a boat. I'm scanning adds and seeing comments like bottom scraped and ready for paint, or freshly applied bottom paint. Recently, I saw photos of a boat covered with barnacles and just all kinds of other hairy mess on the bottom of the boat. My question is: How much trouble is that to clean off? Is it a major project, or something that gets knocked off in an afternoon with a pressure washer? Is it as bad as sanding and buffing out badly oxidized gelcoat? Is it in the category of restoration, or is it general maintenance and not really that big of deal.

Secondly, if I were to bring a boat covered in barnacles and other crud from the south and bring it up north, clean it off in my yard, does that stuff just die off, or am I creating an environmental hazard? I do not live near any water, so I don't think there would be any immediate run off problem. Obviously, I would clean the boat off before putting it in the water up north.

[SlowButSteady]

1) Cleaning the bottom isn't all that difficult. Two guys with big "putty knifes" and a pressure washer can get about 98% of the fouling organisms off in 15 minutes to a half an hour, depending on how far the previous owner has let it go. The last 2% or so will be the basal plates of barnacles and some remnants of hard-shelled tube worms and tube snails. A light hand sanding and/or attacking them with a Scotch Pad will take almost all of them.

The real pain is taking off any old bottom paint; that involves lots of scraping, peeling, sanding, and cursing; followed by copious amounts of beer and aspirin.

2) As long as you stay on the same coast, you need not worry about introducing exotic species. Almost everything on the bottom of a boat (all the fouling critters, anyway) gets there via planktonic larvae, and those can disperse quite easily up and down the coast. Going between oceans, or between coasts of the came ocean, is a different story however.

[sailingdog]

It depends... in some cases it can be very difficult to scrape off. If the barnacles manage to get a full hold, they can be very difficult to remove. However, if the barnacles were affected by the bottom paint, they can often be removed by powerwashing.

If you brought the boat from salt water in to fresh water, the stuff would die, but you'd still have to physically remove much of it.

It generally isn't as bad a sanding and buffing oxidized gelcoat. Of course, with proper bottom painting, regular scrubbing of the bottom, and regular use of the boat, especially with an ablative paint, you can avoid having much of a problem at all. The growth issue is usually far worse on boats that just sit for long periods of time.

[mitiempo]

You say "clean it off in my yard".

Best to clean off right after hauling out. If you wait the job gets much worse.

[QuickMick]

another consideration is what you will be using the boat for. if you plan on racing you will probably want to do it more often (annuallyish), if for casual use every few years would probably work just fine. if you decide not to DIY, a lot of marinas offer deep discounts for work done in the off season.

[Daveinet]

We are talking about a boat that is for sale, so who knows how long it has been out of the water. The photos show the bottom of the boat, well ok, they show where the bottom of the boat should be, all you can see is shells, growth and mud. The price is cheap, trying to evaluate if its worth pursuing or not. The interior of the boat shows to be average for its year, so not terribly neglected, but the exterior top side is solid mildew and the bottom as previously described.

What does someone typically pay for a job like that being done on a 24 foot boat? That would help me gauge the asking price, regardless if I clean it or have it done. Of course the second problem would be the potential for blisters. I'm assuming one would be hard pressed to inspect for blisters without cleaning it. The boat brand/model is not prone to blisters, but who knows.

The boat will be used for day sailing/trailer sailing. I've thought through a few mods to make trailer sailing a little more practical.

[Sabreman]

While nearly everyone has an opinion regarding how to do it, no one likes bottom work. Having survived countless cleanings on my boat and others while working in yards, some opinions follow:

1. Never, ever haul a boat with growth and allow it to dry. Pressure wash immediately after hauling. The vast majority of growth will blow off or can be scraped easily with a putty knife. Then you can haul it wherever you like.

2. If the bottom dries (i.e, much more than an hour), you pretty much have to sand it down.

3. After the boat dries, work with a tarp under the boat to catch debris. That is, when prepping for new paint or when removing all the old paint.

4. Sanding/scraping/peeling to bare gelcoat is a real job and one that many people leave to a yard. If you chose to take this route, there are many threads on SailNet discussing options and techniques. IMO, it's much more work that buffing a hull, in part because you're working overhead. We did our hull in 2009. Photos follow Victoria Bottom Stripping & Fairing

5. Bottom paint is generally applied yearly. An exception is ablative paint that may not have to be reapplied depending on thickness of the base and the type. Not all ablative paints are multi-year and can not be relaunched. Micron CSC and Pettit Hydrocoat are examples of multi season, ablative paints.

6. Sanding is required prior to overcoating. I can sand our 38' hull in 2 hours using a 6" random orbit sander w/ Shop-n-vac.

[sailingdog]

Yes, the stuff dries to a concrete like consistency...much easier to take it off when it is fresh out of the water.

Originally Posted by mitiempo

You say "clean it off in my yard".

Best to clean off right after hauling out. If you wait the job gets much worse.

[SlowButSteady]

It all depends on where you are, the specific yard, how much of the "dirty work" you do yourself, whether you decide to add a barrier coat before you put on the bottom paint, et cetera. Best thing to do is to ask a few local yards what they charge for a bottom job, how much they charge for just a haul-scrape-pressure wash, how much they charge for lay days, how much various options (barrier coat, blister/thru-hull repair) might cost, how much they'll let you do yourself, et cetera. Around here (SoCal), that size boat would cost anywhere from a few hundred bucks (if you did most of the work yourself, and didn't need many lay days to do it), to well over a thousand (if the yard did everything, and you had them completely redo paint/barrier coat... more if you had to take care of a lot of repairs).

[danstanford]

It looks like our boat has been epoxied at some time in her history and then maybe bottom painted after. Since we are sailing in fresh water exclusively, is there any need to paint the bottom? It looks like in some areas the paint has worn through to a different colour, but there is a lot of material there before you get to gel-coat.

Dan