I recently did a pre-purchase survey for a customer of a 2003 FRP yacht with inner FRP matrix. This was the early days for this method of construction for this branch of the boat building company.
Tap testing and moisture readings taken inside and out side the vessel led me to suspect that the flanges of the inner matrix (frame) were not correctly attached and may have been attempted to be rectified either in the factory or at a later date.
I advised that in order to confirm that there was water under the matrix flanges and therefor the bonding was not effective that a core sample should be taken. This was agreed between seller, potential buyer and broker.
This was taken and the results are here, clear to see. The white at the top is the only part bonded. The current owners were blissfully unaware. Remedial action is required by professional FRP company . see core sample being taken in youtube link below.
