Peeling roof paint. What's caused this?

[koukouvagia]

 

There’s a chap on our mooring who’s just bought a twelve month old boat. The rest of the paintwork is fine but something has gone seriously wrong with the roof. It’s as though someone has attacked the roof with a Stanley knife and where the cuts have opened up, the paint is curling away.

Any ideas on what has caused this? My guess would be that it must be down to faulty preparation in some way. The boat painter is at a loss to account for the damage, but is prepared, for the sake of goodwill, to pay £400 for the roof to be repainted. Personally, I reckon that’s not enough, especially if it’s got to be stripped back to the bare metal.

 

[Guest]

Do you know what sort of paint it is? I'm no expert, but that paint doesn't look like it has been applied to a properly prepared surface. Maybe some contamination present such as silicon polish residue?

Edited October 6, 2013 by Guest

[BD3Bill]

Someone's been cutting stuff with a Stanley knife (flooring/lining) up on the roof.

Guilty as charged myself, face palm!

Red oxide primer is not a top coat and will allow the ingress of water, Guessing though as to the paint there.

If the job is only 12 m.o. I think I'd be alight too!

[cheshire~rose]

There has obviously been some sort of reaction to something. It could be something that was on the roof prior to it being painted or something that has contaminated the roof afterwards. If it has affected the entire roof and no where else on the boat then I would say the problem with the preparation of the roof. Whatever has caused it was not cleaned off properly.

 

Silicone contamination gives an effect called "fish eyes" which appear to be an small roundish area of paint that is thinner than the surrounding paint. there will be a number of these over the entire surface

 

like this:

 

[jelunga]

There has obviously been some sort of reaction to something. It could be something that was on the roof prior to it being painted or something that has contaminated the roof afterwards. If it has affected the entire roof and no where else on the boat then I would say the problem with the preparation of the roof. Whatever has caused it was not cleaned off properly.

 

Silicone contamination gives an effect called "fish eyes" which appear to be an small roundish area of paint that is thinner than the surrounding paint. there will be a number of these over the entire surface

 

like this:

 

When I was in the motor trade in the 70's we called that a"British Leyland " paint job.

[Québec]

We've got something very similar, in a few patches. Painted the roof two years ago, and has started to appear since the summer. It could b a number of things, but wondering if is isn't something to do with the v. hot summer, constant metal expansion and contraction, and the paint not being as 'elastic' as it could be.

[churchward]

 

There’s a chap on our mooring who’s just bought a twelve month old boat. The rest of the paintwork is fine but something has gone seriously wrong with the roof. It’s as though someone has attacked the roof with a Stanley knife and where the cuts have opened up, the paint is curling away.

Any ideas on what has caused this? My guess would be that it must be down to faulty preparation in some way. The boat painter is at a loss to account for the damage, but is prepared, for the sake of goodwill, to pay £400 for the roof to be repainted. Personally, I reckon that’s not enough, especially if it’s got to be stripped back to the bare metal.

 

It does look odd. Although straight lines it looks more like a contaminant than cuts.

 

I may be getting the wrong end of the stick but if your friend has just bought the boat they must have known the paint was in this condition? If so the I assume he paid an appropriate amount of money for the boat with this knowledge and therefore £400 would seem generous.

Edited October 6, 2013 by churchward

[koukouvagia]

 

I may be getting the wrong end of the stick but if your friend has just bought the boat they must have known the paint was in this condition? If so the I assume he paid an appropriate amount of money for the boat with this knowledge and therefore £400 would seem generous.

The damage materialised recently, six months or so after he'd bought the boat.

[Ex- Member]

I've seen this before, I'm pretty sure it's because the Grey primer has been left exposed to the sun too long and over hardened, if this is the case and it isn't properly rubbed down before over coating then the top coat just won't adhere like it should. This also happens with Red Oxide primers, and most likely any others.

[LEO]

Hi,

 

Hope it's not contagious that boat is moored next to mine!

 

L.

 

PS. Not sure about this as some patches are rusting slightly, it does not look like a silicone related problem, I suspect a paint incompatibility problem.

 

Kitman are you out there?.

[Bee]

On the big patch on the left the paint simply hasn`t adhered to the undercoat, as for the lines I would guess it`s the same problem, I expect the answer is to sand the whole lot back and start again, by the way beware of using floor paint, a lot of it is not suitable for exterior use, I used Screwfix red floorpaint and every year I have peeling patches, often with water under the paint and it is a damned nuisance.

[ditchcrawler]

, by the way beware of using floor paint, a lot of it is not suitable for exterior use, I used Screwfix red floorpaint and every year I have peeling patches, often with water under the paint and it is a damned nuisance.

Thats OK I have that with posh paint

[alan_fincher]

I can't believe how uncannily straight the lines are.

 

No idea whatsover, I'm afraid, but I'm struggling with the idea that it is solely about a lack of flexibilty in any layer of the paint.

 

I can just about see that causing cracking along a series of different lines, but I can't see it causing cracking along two perfectly straight lines each of which cross each other at an angle. Whichever crack appeared first has already provided a break in the paint, and relieved some stresses, so the other line would then need to be two separate cracks that each formed afterwards, but still align perfectly. That would seem distinctly odd!

Would this be a boat assosciated with a very large flagpole, and delusions of grandeur that it is part of some mythical manor?

[Timleech]

I can't believe how uncannily straight the lines are.

 

 

 

Would this be a boat assosciated with a very large flagpole, and delusions of grandeur that it is part of some mythical manor?

Don't understand that bit,but I expect Erich von Daniken would have come up with an answer.

 

Tim

[churchward]

I can't believe how uncannily straight the lines are.

 

No idea whatsover, I'm afraid, but I'm struggling with the idea that it is solely about a lack of flexibilty in any layer of the paint.

 

I can just about see that causing cracking along a series of different lines, but I can't see it causing cracking along two perfectly straight lines each of which cross each other at an angle. Whichever crack appeared first has already provided a break in the paint, and relieved some stresses, so the other line would then need to be two separate cracks that each formed afterwards, but still align perfectly. That would seem distinctly odd!

 

Would this be a boat assosciated with a very large flagpole, and delusions of grandeur that it is part of some mythical manor?

I agree it is odd being in straight lines. I don't think it is cuts though you can see some of the lines are just where the paint is blistering up along a line and the at some point some of the blisters have split. It does seems unusual.

[Kwacker]

Could the straight lines be something to do with the topcoat being applied by roller?

The over-hardened primer/undercoat theory sounds good to me.

Edited October 6, 2013 by Kwacker

[kitman]

Kitman are you out there?.

 

Hmm? Oh sorry I 'm here...I got a bit distracted by 21 photos on facebook showing the 'Awesomness of yoga pants'!

 

About that roof, I would say the paint is brittle, lost it's flexibility through some process. Could of happened on application or could be owner has washed it with the wrong cleaner i.e. something with a lot of detergent in. Fairy liquid ringing a bell?

 

So how old is the paint on the roof exactly? was it 6 months old, 6 month ago? or 12 months old, 6 months ago?

[Daiboy]

Does this remind you of something

 

Do bee, Do bee, Do bee, Do bee

 

 

[LEO]

 

Hmm? Oh sorry I 'm here...I got a bit distracted by 21 photos on facebook showing the 'Awesomness of yoga pants'!

 

About that roof, I would say the paint is brittle, lost it's flexibility through some process. Could of happened on application or could be owner has washed it with the wrong cleaner i.e. something with a lot of detergent in. Fairy liquid ringing a bell?

 

So how old is the paint on the roof exactly? was it 6 months old, 6 month ago? or 12 months old, 6 months ago?

 

Callow youth! how times change - we used to get by with 'Health & Efficiency' - studying the mid tones in B&W pictures to help with our photography of course.

 

I think the paint is about 12/18 months old, as far as I know in this period of ownership it has not been washed with anything other than H2O.

 

Another boat built by the same guy using the same technique and similar materials is still OK (so the current owner is informed).

 

L

[Doorman]

Could it be 'self harming' ?

[bizzard]

I've seen a couple of boats roofs painted with the red Leyland floor paint, the one which has tiny flecks in the mix and they seem to have weathered ok, But I wouldn't use it.