"Moisture Readings" can be very confusing. First, such meters only
measure the 'surface moisture'. Second these 'meters' are rarely
calibrated. Third, an instrument is only as good as the operator who
uses it.

Virtually ALL plastics are permeable/porous in nature so if a hull were
ever i n the water it would naturally have 'moisture'. That the hull
shows NO evidence of blistering means that the laminate structure is
intact, doesnt have a degradation by 'hydrolysis' - a decomposition of
the stryene 'binder', etc. At over 18 years of age it would be VERY
doutful that this hull would form 'blisters' in the future.
Blistering primarily occurst in the matting layer between the gelcoat
and the structural roving/cloth layers .... and is a cosmetic layer.
Bilistering usually forms when the original layup doesnt have
sufficient resin, leaves teeny air/gas spaces along the glass fibers
into which moiisture can permeate.

With zero blisters now or in the past, you probably have a VERY good
hull that would not blister in the future ..... but no guarantee as
sometimes when you move a blisterless boat from salt water to fresh
water blister sometimes become evident.

Usually blisters are hype and unless the blistering is deep down into
the structural part of the laminate there will be NO problem. Beware
of DIY blister repair as this usually makes the hull VERY vulnerable to
further significant blistering .... sometimes to the extent that a hull
is beyond repair. Proper blister repair is to usually entirely remove
the degraded (matting) layer (peeling/cutting .... not grinding nor
sandblasting, etc.) and rebuild with a resin-rich layer to prevent
future water permeation.

NO visible blisters or just a few here and there on an old boat ......
a good one!



In article .com,
Izmack wrote:

Hi Everyone,

We are looking at at late 80's Trojan F32 with very high moisture
readings in the hull, but zero signs of blistering either currently or
in the past. Our surveyor, who was VERY thorough, said the following:

"Bottom was found in above average condition, having no signs of
blistering,crazing or delamination. High moisture levels were noted,
ranging between 80-100 and some crusty deposits were noted, indicating
laminate hydrolysis. Recommendation to dry store vessel each winter off
season to maintain current good condition. If vessel is left overboard,
some blistering or delamination could be expected over time."

I know I'm asking for a barrage of opinions, but, considering it's a 16
year old boat and the fact we are first time boat buyers and that the
rest of the survey was above average, what do you all think? And -
will future buyers balk at resale?