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'No chalk' hull survey


tonyreptiles

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Hi All,

 

By boat has just been surveyed in preparation for its insurance renewal. As you'll likely know, most companies require a hull survey when the boat is over 25 or 30 years old. I'll be having it blacked while it is out of the water too.

 

I went to meet the surveyor at the boat this morning, but he had already been and gone. Estimated time on site was less than an hour.

 

However, when I looked at the boat there were none of the usual chalk marks on the hull, signifying that the thickness had been checked. I'll be calling him shortly to inquire, but I thought I'd check with you folk first - is it likely that a hull survey can be done without chalking the hull? Is there some new technology that I am unaware of?

 

Is there a possibility that the surveyor has pulled a fast one in the hope that the lack of chalk evidence would have been covered by blacking a few hours later? After all, if I hadn't turned up unannounced, the first coat of blacking would have been put on just an hour after he had left.

 

Am I being paranoid?

 

Thanks

TR

Edited by tonyreptiles
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Chalk is just a visual reference when the surveyor has an old style depth gauge. He surveys the hull, then goes round and collects the chalked depths to a sheet of paper for use in the survey.

New gauges record this in the unit itself, and are then downloaded via USB or Bluetooth.

You need to look for 3 small scraped areas in a vertical line, about 10 feet apart along the length of the hull below waterline. This is where the measurements will have been taken. There may also be random scrapes where pitting is suspected.

 

Or he may just have guessed........

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Chalk is just a visual reference when the surveyor has an old style depth gauge. He surveys the hull, then goes round and collects the chalked depths to a sheet of paper for use in the survey.

New gauges record this in the unit itself, and are then downloaded via USB or Bluetooth.

You need to look for 3 small scraped areas in a vertical line, about 10 feet apart along the length of the hull below waterline. This is where the measurements will have been taken. There may also be random scrapes where pitting is suspected.

 

Or he may just have guessed........

 

 

Or worse, it could have been what is called in the property business a "drive-by survey"...

 

Welcome back Tony, I thought you'd decamped to a coastal boat!

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Welcome back Tony, I thought you'd decamped to a coastal boat!

 

Not yet Mike - although that's still on the cards. :-)

 

 

I'm really not confident about this survey. There is no evidence of his work that I noticed. Might I have missed the scraped sections? I noticed nothing to signify that he had been there, apart from the fact that he picked up the key from the marina reception and returned it less than an hour later.

 

Is three points of checking enough to discern the thickness of the hull on a 50 foot boat??

 

Cheers

Tony

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When we have had Fulbourne's hull surveyed the surveyor has used an angle grinder to remove blacking down to bare metal at each location where the thickness is measured. This all takes time, and leaves a grid of bare metal patches all over the hull sides and bottom, as well as the chalked thickness figures alongside. If you are not getting this I would doubt you have had a proper hull thickness survey.

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The three points every 10 feet are a basic minimum, baseplate is one of those 3 points. Front end and counter are usually done at less than 5 feet apart.

Areas for closer inspection usually are where the bathroom, kitchen and water tanks are inside.....most common places for internal corrosion.

 

 

One surveyor who I have seen recommended on here by some, and slated by others recently did a hull survey in 10 minutes, checked the hull visually and did just 3 test areas. His explanation for this was good hull builder, epoxy coated and obviously no pitting!!!

Edited by matty40s
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Out of interest, is £250 for such a survey a reasonable cost?

 

Thanks

TR

 

£250 sounds cheap for a full hull survey to me.

 

I'd say for a boat that length £400-£500 might be more normal, but happy to be corrected if wrong - the surveyor I use is a specialist in old historic boats, and maybe costs are higher than for modern ones with less complexities?

 

In what state was the boat when the survey was done? Pressure washed, ready for blacking? Apart from the lack of chalk, it sounds like there were no scraped off or ground off areas in the old blacking, (correct?), so I think the only possibility if not is what Matty is suggesting about newer technologies, which I have not witnessed in use.

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When we have had Fulbourne's hull surveyed the surveyor has used an angle grinder to remove blacking down to bare metal at each location where the thickness is measured. This all takes time, and leaves a grid of bare metal patches all over the hull sides and bottom.

That echoes what happened to WotEver.

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I would be giving the surveyor a call and asking why he had to leave suddenly, and when he'll be back to do the job.

 

And if the answer was not highly satisfactory I would then be finding a proper surveyor.

 

The chalking is not just about recording the measurements, it's about recording the locations they were taken so that a plan can then be drawn up.

 

Be very suspicious of surveys that seem to involve only a regular grid of measurements. A proper job involves a whole lot of whacking with a hammer and listening to get a sense of where the metal may be thin, and measurements taken accordingly. That all takes time.

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How did you estimate the time to be an hour or less? Is it possible that he was there for longer? Did the marina log his arrival and departure time? Their recollection could be faulty. Humans are very unreliable witnesses however well intentioned. I would wait for the survey and see how many points were measured. do you know the original thicknesses? Surveyors need to protect their reputations to get work and it seems odd to me that he would skimp on an easy job. If he belongs to a trade body or competent person scheme you could ask them for advice.

 

Who recommended him?

 

What qualifications has he to conduct surveys?

 

Please do nothing that might identify him (legal reasons ;-) )

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An hour or so is not a lot is it. Any of us can do a quick visual check in that time and to be honest that will actually tell you quite a lot. You can see pitting, have a good guess at the depth, see how much there is, where it is, if its worth spending time welding some of the pits or just paint over them, crawl underneath and scrape the rust 'flowers ' off , or not if its been pressure washed. Inside lift as much flooring as possible and see if it is horrible and rusty (sheets of scale) or just a bit damp and nasty. The only thing you can't do is actually use an instrument to measure thickness unless you pick a really nasty bit, drill a hole, measure it and weld it up again. I would reckon that for a fairly modern, heavily built pleasure boat that would do.

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The boat was on hard-standing and had been pressure-washed before the survey. It was only blacked a couple of years ago and so still looked in quite good shape, blacking and corrosion wise.

 

I got the timings of his attendance from the marina office, where he arrived to pick up the key. They open at 9am. I arrived at just after ten and he'd been gone a while. Office estimated less than an hour and he was recommended (along with several others in the area) by the folk at the marina.

 

I spoke to the surveyor a few minutes ago and am much reassured. He was able to give me some measurements which largely align with my expectations an the thicknesses seen in the previous survey. I might have missed the bare-metal testing areas when I walked around the boat. It seems that there is very little pitting - less than 0.5mm on this 30 year old boat. Good steel apparently. Surveyor was complimentary of the hull and the hull care that has obviously been taken.

 

I'm prepared to give the benefit of the doubt given how he came across in the conversation. Was forthcoming and communicative, and he answered my questions without delay or malice. I'm guessing he recorded thicknesses on paper, rather than on the boat.

 

I guess, when it comes to the integrity of my hull I'm cautious and require reassurance. It's an important day. I think we're OK though.

Thank you all for your input and advice. Very reassuring, as usual.

 

Regards.
TR

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I had a hull-only survey done by Craig Allen last year, and that was £250 IIRC.

 

No chalk marks but no problems found either, so perhaps no point. I accompanied him for the survey which took about two hours from memory.

 

Bear in mind time on site doing a survey is only half the work. writing up the survey back at the office, posting it, billing the customer and checking they paid also takes up time which to the customer seems invisible.

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I understood that the hammer and chalk is a bit old school but does give a experienced surveyor a good idea of the hull condition. They than use a ultrasound (I think) machine all along the hull but have to add some grease type substance (as they do if you have ultrasound on yourself, eg scanning pregnant ladies) and scrape off old blacking. You should see evidence of blueish blobs all over the hull. Obviously best to survey before blacking as you would have to go over the spots again. I guess you only paid for a hull survey rather than a full survey - my last survey cost just under £500 (46ft nb).

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When we have had Fulbourne's hull surveyed the surveyor has used an angle grinder to remove blacking down to bare metal at each location where the thickness is measured. This all takes time, and leaves a grid of bare metal patches all over the hull sides and bottom, as well as the chalked thickness figures alongside. If you are not getting this I would doubt you have had a proper hull thickness survey.

 

From Fulbourne's survey:

 

Chalk-XL.jpg

 

chalk%202-M.jpg

 

Am no expert but would be concerned if I couldn't see any bare patches

 

Tim

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A modern uljtrasound thickness tester does not actually need to be on bare metal, whereas the older ones did because they only measured to the first sound reflection. They do still need the coupling gel though. Trouble is the gel is now much less special and several common products can be used.

 

N

  • Greenie 1
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Mine cost £250. Forget how long it took, around an hour I think, freshish paint on the hull, no scraping (obviously as it's U/S) and no chalk marks.

 

As you've discovered, nowt to worry about, times move on and technology makes things easier and faster.

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Thickness tests at regular intervals are not required or significantly informative as I understand. Nothing is likely to happen in the middle of the plate. Looks good but adds little or nothing.

 

What is much better and less intrusive, is a few tests in key areas where issues are most likely.

 

As said, not all thickness gauges need direct steel contact, although a lot still use older or more basic units which do.

 

 

Be very suspicious of surveys that seem to involve only a regular grid of measurements. A proper job involves a whole lot of whacking with a hammer and listening to get a sense of where the metal may be thin, and measurements taken accordingly. That all takes time.

Indeed

My strike through.

 

 

Personally it sounds like the hull is in good shape, and if both you and the insurance are happy the job is done.

 

You are far more likely to sink due to a fitting failing or external influence than failure of the hull I would say.

 

Daniel

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