Survey advice.

[booke23]

I viewed a 2002 Narrowboat yesterday and I was able to read a full survey from 2019. The survey was positive with only minor defects noted. The Hull is 10/6/4 and the ultrasound report is as follows: 

 

Baseplate - max 9.5mm/min 9.1mm, average 9.5mm

Hull sides - Port, max 6.0mm/min 5.5mm, average 5.8

          Starboard, max 5.9mm/min 5.5mm, average 5.7

 

In addition the surveyor noted:

 

"Some historic shallow pitting was seen about the waterline however this is not progressing any further and shouldn't with regular blacking. The base plate is covered in a thick layer of encrusted marine growth and when scraped away revealed a covering of black microbial influenced corrosion. This will slowly eat away at the steel over time and would benefit from cleaning off with a pressure washer and some dilute bleach to kill the microbes." 

 

The MIC concerned me slightly and if I buy the boat I will have my own survey carried out. Is this a reasonable report for a 17 year old hull?

[Alan de Enfield]

23 minutes ago, booke23 said:

The MIC concerned me slightly and if I buy the boat I will have my own survey carried out. Is this a reasonable report for a 17 year old hull?

 

MIC is not easy to get rid of and can 'eat' a boat very quickly.

 

The survey was 2 years ago - if action was not taken at the time then there could be very little bottom left.

 

 

A biased report from a blacking supplier, but the underlying information is true and valid for consideration.

 

And a further couple of scientific reports.
MIC is SERIOUS and its eradication not undertaken lightly.

 

 

MICROBIOLOGICAL-CORROSION.pdf Metal Corrosion in Fresh Water.pdf Microbial Corrosion Marine.pdf

Edited June 17, 2021 by Alan de Enfield

[booke23]

Thank you @Alan de Enfield Very interesting reading. 

 

I'll ask if any remedial action was taken at the time. 

[booke23]

Just to conclude this topic, I did not proceed further with this boat so I never will find out what state the base plate is in!