Bottom paint condition, pre-purchase

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isophase

Member
Joined
Apr 17, 2024
Messages
11
Location
Hamilton, ON
Hi all, looking for some wisdom from the crowd here. My wife and I are looking to buy our first boat, a trawler. I've got lots of experience using and teaching on sailing and power boats but zero ownership experience. We have found one that looks good. Taking a second look on the hard, the bottom paint is in pretty rough shape though. It's layer upon layer, just flaking off from pressure washing or even with light scratch of a fingernail.

This boat was mostly freshwater for decades, but recently completed the Loop. We'd be keeping it in fresh water. Current location & where we'd keep it are in Canada so the boat is out of the water November-April. Earliest we could sea-trial is April-May.

I'm thinking options, in order of preference:
1) Make stripping and re-painting a condition of purchase. The hull will be nice and dry by April having been out of the water for months, plus it's already hauled out. Get a full season with the hull properly protected assuming sea-trial goes well.
2) Accept seller's offer of local sanding and touch-up, buy as-is at a lower price, short trip home (<200mi). Use it locally for a season (June-October), then do the job right (soda blast, epoxy barrier, antifouling) the next spring
3) Same as (2) but immediate haul and repaint on top of the old on arrival home. Not as nice because I lose a bunch of the season. Not sure if this would even work with the hull recently wet and the under layers flaking.

I get the seller's reluctance to sink more money in, but this seems like significant deferred maintenance. How much harm could I do if I used it as-is in fresh water for five months?

Thanks in advance!

Jeff

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@Mainship Pilot - Sounds so simple! Maybe I am overthinking. Appreciate the input.
From the small sample shot you sent, the bottom looks normal for a boat that is due for a every two year bottom service, which is what we do here in So Cal, as our boats live in the water year round. Unless there are egregious blisters, or thru hulls that are compromised, coat and go!
 
A blast job would give you several years of use. But more important would reveal hull damage or repaired blisters currently hidden. I think if'n it was me , id offer to split the blast/paint bill contingent on no prior hull damage revealed upon blast. Also resolves the issue of what type of paint is on there, ablative or not
 
A blast job would give you several years of use. But more important would reveal hull damage or repaired blisters currently hidden. I think if'n it was me , id offer to split the blast/paint bill contingent on no prior hull damage revealed upon blast. Also resolves the issue of what type of paint is on there, ablative or not

If I were the seller I'd reject that offer. There is no need to remove paint to check for blisters.

When I walk around the yard where I'm parked on the great lakes, half the bottoms look like that. I fully understand the reluctance of owners to pay five figures to have the bottoms stripped and refinished. For most there's no justification in doing so. I wouldn't label that deferred maintenance.
 
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Really hard to see blisters that have been repaired & painted over. Like how big & how many.
 
If I were the seller I'd reject your offer based on full bottom work. If I were you and intended fresh water use only I'd touch it up and go boating.
 
Really hard to see blisters that have been repaired & painted over. Like how big & how many.
I guess everyone has different concerns. A good surveyor should be able to determine bottom condition without removing the paint. It's an extreme solution to address an uncommon concern, in my experience.
 
Looks like it's drew for a paint job . If it had blisters ,they would show as the boat dried . Water would contimue to leak as the hull dried . I would not accept your offer as to blast bottom and repair and paint . You should be able to see ,feel any bristers and your surveyer could mark and show you . If that's the boat you want , buy it ,have bottom sanded and painted ,and any blisters repaired in the spring .
 
@Mainship Pilot - Sounds so simple! Maybe I am overthinking. Appreciate the input.
A broker friend advises all sellers to repaint the bottom lickety split after the boat is hauled. It improves overall presentability and largely avoids these sorts of concerns with first-time buyers.

It sounds like you're overthinking. Put a complete bottom job on your to-do list, don't make any planned big changes in the first year, and see how your list orders out after using the boat. I suspect this won't be near the top.
 
Observations: looks like the black bottom paint wasn’t applied correctly to the blue bottom paint-maybe not sanded enough (or at all) to allow it to adhere.
Perspective: I am in fresh water year round. I just did a bottom job after six years (I did the previous bottom job). I was shocked at how well the bottom paint held up. I could have gone a couple more years. My neighbor, who has a floating home with fiberglass pontoons, does a bottom job every 10 years.
As people stated above, you could slap some bottom paint on and get by for quite awhile.
Make sure you have aluminum anodes!
You should be able to see blisters if they exist-who cares if they were repaired.
At some point you would want to get rid of all the bottom paint and barrier coat and bottom paint.
 
Some where, a layer of bottom paint was poorly prepped. It is now flaking off. What you see is only the beginning of a continuing issue. Every time you pressure wash the bottom more paint will flake off.

There are two solutions.

Just roll on more paint every time you haul out and not worry about having a cottage cheese looking bottom.

Sand off all the paint, barrier coat the bottom and repaint.

Don't ask the seller to repair the bottom, you will get a worthless repair so what's the point. Either accept it and move on or ask for $6,000 off to repair the bottom correctly. It will cost more than $6,000 to fix this but the seller isn't selling you a brand new bottom so some where in the middle is a fair price reduction.

Sellers might bauk at this but as a buyer be careful buying other's liabilities and poor workmanship.

I am currently in the yard dealing with this very problem, only this time I'm spending real money to correct it after glossing over it for the last 10 years.
 
Yup, touch up the flaking and it will last another 4-5 years in fresh water. If you really want the boat don't let this be a show stopper.
 
If you plan to keep the boat in fresh water it’s a real non issue. Bottom paint does nothing in fresh water. Just keep blasting off the paint each time you haul out.

If you plan to move the boat to saltwater it’s a bit more of an issue as you will be doing touch up bottom paint every time you haul out.

You can cruise saltwater for about 2 weeks with no issue before returning to freshwater. Longer stays should have bottom paint.

As I mentioned, I have been doing the touch up routine for 10 years. Since I was already having an extended stay in the yard I took this opportunity to correct my issue.
 
I think seasonal fresh water usage is key. Antifouling requirements are minimal, and blistering has been less prevalent. So there is less of a case for barrier coats etc.

Maybe this is less the case in the US, but in Canada the bottom paints and formulations have changed a lot over the last 50 years. The root issue may be incompatibility between different paints rather than poor prep. I remember many years ago a commonly used tin-based paint that was discontinued, and was very difficult to properly overcoat with the available replacements.
 
I'm mildly surprised at the "roll-&-go" consensus. Even under the best of circumstances, bottoms cannot be repainted indefinitely. At some point they need to be stripped and the bottom reprepped. As @tiltrider1 suggests, the pictures show significant signs of paint failure exacerbated by poor prep. Whether it's end of life cannot be determined from pictures. What did the survey say?

That said, this is a negotiable point for a bundled credit, not a single line item where at one extreme you ask the seller for a new bottom and get a middle finger response from the seller - it's a used boat, you get a used bottom. If you've already negotiated sizeable credits or significantly lower price, you're unlikely to get more here. If the boat was advertised as turnkey and ready to go, you have a riteous claim for a partial credit.

If this is your biggest issue holding back the sale, you're in great shape. This one is predicable in cost and magnitude.

Good luck

Peter
 
If it's ablative paint and the still good black sections are still doing their job and preventing growth, I'd just knock off any loose paint and then touch up the worn spots. That'll let the excess (and possibly poorly adhered) paint buildup continue to wear down. You can help this with some sanding, and when you get the bottom to a good state (or when fouling is becoming a problem) you can throw a coat or 2 of paint on the whole thing.
 
To everyone who's weighed in so far: thank you sincerely for your time and input. This has been extremely helpful. I'm a n00b prone to overthinking so the reality-check is much needed and valued.

@tiltrider1 Valid point about getting the job done right, that occurred to me as well (after I made an offer; better late than never). Realized it would be a PITA for the seller to arrange the work, and they want cash out not cash in to the boat. From here and a friend I got a consensus that it would be good to do but not urgent so should manage and pay for it myself.

@mvweebles No survey yet, that will be in the spring. Based on pics, my chosen surveyor has said it doesn't look too bad as far as pictures go but no promises because he needs to see it and touch it. Seems reasonable. As far as that being the only issue... previous purchase survey a few years ago was clean. It's got two of the little-loved Volvo TMD41A with MS4A cone clutch but I've read the extensive discussions on that and accept that it is what it is.


I think part of my reaction (aside from pure lack of experience) is that most of the bottoms I've seen are sailboats in fresh water (summer peak temp low 70's F) which have been very well tended. Mostly VC17 thin-film and a lot of racers and racer-cruisers around the yacht club so very conscious of keeping it slick.

So where are we now? Had submitted an offer with condition of a strip and re-coat on the bottom. Got a counter-offer at higher price with just a local sand & touch-up. Just submitted a final offer to the broker with bottom as-is and a price a few percent below the counter. Should find out in a few days if it will fly, then it'll be a long winter until May for launch/survey/sea trial.

Thanks again - this forum is a real treasure and I hope to be back soon with my own trawler, more questions, and eventually some answers too.

Jeff
 
I agree withnthe concensus so far.... if you like the boat and other things check out buy it. Do a modest touch-up and complete 1st season. Then decide whether you continue with better prep & repaint either sections each year or complete redo. I've stripped, barrier coated and bottom painted one boat but would never DIY again. Bottom paint alone provides little "protect" of the hull as farcas blistering goes... only prevents build up so I don't see less than an ultimate refurb job causing and damage that is not already evident. Short northern seasons are easier on hulls than Southern rarely hauled situations.
 
@Bacchus What was the worst part of the DIY? I'm assuming it would be stripping and cleanup. The rest is just a number of layers of epoxy & paint right?
Soda blasting looks promising if/when I go down that road. Sanding sounds grueling and chemical stripping just nasty.
 
I sanded mine many yrs ago. Our1st boat, young and little available cash to hire others, so I did the dirty deed.
Your summary of sanding grueling and chem stripping nasty ( afriend took that route a few yrs ago) are right on. I'd hire the prep if needed in future. You are correct that the multi coat application is easy compared to the prep as long as you are able / interested in spending many hours on your back & crawling around under a hull to do the many coats req'd.

Sanding req'd coveralls, hood, mask/ breather and a couple good foam pads to lay on. Many yards wont allow that level of sanding / stripping or impose plenty of additional reqmt. Then you need to be prepared to move supports for each coat if you want full coverage and don't want to leave pad/ support areas uncoated.

Timing is tricky and you need a 2-3 day window of good Wx and temps. There usva min & max dry time between coats and if you miss the window you need to sand and add an extra coat so goid timing is critical.
 
We once did a hard dry machine sand of my then IG36, post osmosis repair. A disgusting horrible job. But we ended up with a lovely smooth bottom, until....
Eventually the a/f will lose enough adhesion you need to take it right back, soda stripping seems preferred. Until then, you can do a lot to sand as needed, hard or light, reprime bare spots. I think I read the boat will be in freshwater with minimal fouling so getting too aggressive too early seems a waste of time and money(WOFTAM).
 
I think part of my reaction (aside from pure lack of experience) is that most of the bottoms I've seen are sailboats in fresh water (summer peak temp low 70's F) which have been very well tended. Mostly VC17 thin-film and a lot of racers and racer-cruisers around the yacht club so very conscious of keeping it slick.
Right. I have vc-17 on my sailboat, and if I were buying a sailboat I'd be pretty put off by a bottom like you're getting. Most of the older boats did a complete bottom job at some point to go to the thin film.

But on old trawlers there's far less of an impetus. Slickness doesn't count for a lot.
 
Our boat came from Narragansett Bay with a newly-done bottom job and now it's been in fresh water ever since, pulled every winter. The marina power washes the slime off each fall but the bottom still looks fine and it's been nine years now. Fresh water is an entirely different environment. Until and if you take the boat into salt someday, it wouldn't be an issue for me. I don't plan to have the bottom done until just before we have the boat shipped to Duluth to sail back out into the world.

Some of the larger sailboats in our marina do do beautiful Coppercoat jobs every few years, but it's almost entirely for cosmetic purposes because it looks pretty.
 
Some of the larger sailboats in our marina do do beautiful Coppercoat jobs every few years, but it's almost entirely for cosmetic purposes because it looks pretty.
Probably the owners believe that sailing performance improves as well. Lots of sailors really care about having perfect bottoms, and spend lots of effort and $$ getting there. They have different concerns than most power boaters.
 
@Jeff F - it's a well-founded belief. Sailboats, especially more modern designs (hull form somewhere between a a canoe and surfboard shape with fin keel & spade ruder), are quite sensitive to bottom fouling. Sailing upwind, lift/drag ratio is crucial for both sails and hull. When cruising if you want to sail you have to make do with the wind you have, you can't just push the throttle up. A lot of the Great Lakes can be frustratingly light winds for much of peak cruising season. May have had some input on my choice to buy a trawler... :unsure:

Update to all: contract signed, next stop survey & sea trial in May. Slightly jealous of those who can be on the water year-round.

Thanks again
 
My 28’ Cape Dory looked similar back in 2008 when I bought it. It had build up from years of hard coat bottom paints …then a few layers of ablatives over that…many peeling layers…the next year I scraped a good amount of the layers down to the last few original ones then used a dewalt orbital sander and 60 grit to get down to the original gel coat. Took me a few weeks of labor.2 coats of barrier coat and Pettit hydro coat ablative afterwards..bottom still looks new…if I did it now I’d have it blasted…I was a plasterer by trade so was used to overhead work plus was 15 years younger 🙂…good luck ,Mike
 
Hi all, looking for some wisdom from the crowd here. My wife and I are looking to buy our first boat, a trawler. I've got lots of experience using and teaching on sailing and power boats but zero ownership experience. We have found one that looks good. Taking a second look on the hard, the bottom paint is in pretty rough shape though. It's layer upon layer, just flaking off from pressure washing or even with light scratch of a fingernail.

This boat was mostly freshwater for decades, but recently completed the Loop. We'd be keeping it in fresh water. Current location & where we'd keep it are in Canada so the boat is out of the water November-April. Earliest we could sea-trial is April-May.

I'm thinking options, in order of preference:
1) Make stripping and re-painting a condition of purchase. The hull will be nice and dry by April having been out of the water for months, plus it's already hauled out. Get a full season with the hull properly protected assuming sea-trial goes well.
2) Accept seller's offer of local sanding and touch-up, buy as-is at a lower price, short trip home (<200mi). Use it locally for a season (June-October), then do the job right (soda blast, epoxy barrier, antifouling) the next spring
3) Same as (2) but immediate haul and repaint on top of the old on arrival home. Not as nice because I lose a bunch of the season. Not sure if this would even work with the hull recently wet and the under layers flaking.

I get the seller's reluctance to sink more money in, but this seems like significant deferred maintenance. How much harm could I do if I used it as-is in fresh water for five months?

Thanks in advance!

Jeff

View attachment 159358
View attachment 159357
Do not blast! Aggressively sand with 40 grit then inspect for blisters and fare out; then 3 coats of hard paint NOT ablative !! And then a fourth coat on the waterline.
 
Do not blast! Aggressively sand with 40 grit then inspect for blisters and fare out; then 3 coats of hard paint NOT ablative !! And then a fourth coat on the waterline.
Why not?
It sounds pretty effective and gentle on the hull. Sanding sounds like brutal work. What am I missing?

Thanks
 
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