I'm considering purchasing a small steel-hulled yacht, but she does not
have any insulation. I would imagine that the immediate problems in a
European summer will be excessive heat,condensation, and to a lesser
extent, noise. Retro-fitting insulation is an option, possibly in
stages, and I'm wondering whether anyone would have some views on this.
My initial thoughts tend toward the use of foam board, room permitting.
(I know that Alubat offer foam insulation as an option on their
aluminium boats, fitting boards between frames, but I don't know what
material they use - I would imagine that it is some form of polyurethane).

Michael Prewett

Michael,
I am a builder and owner of a large steel boat. Insulation is absolutely
necessary in a steel hull. Corrosion is no problem on the outside, but can
be a nightmare on the inside. Condensation is the culprit. The solution is
to seal the interior metal surfaces from exposure to air. This is especially
true for those surfaces that are hard to get to. That requirement is best
met by sprayed urethane foam on top of a quality paint scheme. It has
incredible adhesion qualities. It is fast to apply, but extensive masking is
required. It has some disadvantages, it is expensive. It is not a closed
cell foam, so it can absorb liquids over time, which are not removable
without gutting the foam. It outgases for a long time, some of which can be
harmful. When exposed to fire, the gasses created are deadly. Once sprayed
and cured, it should be painted with a waterbased flame retardant paint.
This will seal the foam countering the disadvantages somewhat. Polystyrene
foam is another choice. It is of the closed cell variety, it is less
expensive, it is not as messy as urethane and it has a better R rating. It
is harder to use because the adhesives are slow curing. Volatile adhesives
will dissolve the foam. Because of this, it is slower to apply, as clamping
is required. It does NOT seal the steel from exposure to air, so the foam
must be additionally sealed with plastic sheet and outgassing in fire is
also a problem as with urethane. Another choice worth considering is rock
wool. It is less expensive than styrene, faster to install than styrene and
can be purchased in a roll with one side bonded with a plasticized aluminum
foil which will aid in sealing the metal surfaces from air as well as having
a much better R rating and an infra-red reflector. Probably the most
endearing quality Rockwool has is ease of maintenance and accessibility. It
is easy to remove and replace if it gets wet, as well as being fast to
remove in an emergency. One last point that is related is bilge protection,
which is also critical in steel hulls. Your insulation must not go much
lower than the waterline, typically only to the cabin sole. So where water
congregates requires special attention. There, you want to derust at well as
possible. then use a rust converter like a weak solution of phosphoric acid
or a commercial equivalent like Fertan, wash out well with water. then an
etching two part epoxy primer followed by a compatible bilge paint. But,
where water can sit, additionally spray that area with a special marine
paraffin based wax similar to Ziebart for cars. This material never quite
hardens and continually seals against water. Completing these steps with
just occasional maintenance will allow the hull to remain viable for well
over 100 years. One last note, commercial ships and super yachts use
Rockwool and the paraffin wax solutions almost universally.
Steve



"Michael Prewett" wrote in message
...
I'm considering purchasing a small steel-hulled yacht, but she does not
have any insulation. I would imagine that the immediate problems in a
European summer will be excessive heat,condensation, and to a lesser
extent, noise. Retro-fitting insulation is an option, possibly in stages,
and I'm wondering whether anyone would have some views on this. My initial
thoughts tend toward the use of foam board, room permitting. (I know that
Alubat offer foam insulation as an option on their aluminium boats,
fitting boards between frames, but I don't know what material they use - I
would imagine that it is some form of polyurethane).

Michael Prewett

Thanks for that very comprehensive reply; there's a lot of food for
thought there. I'm going to have a first sight of the boat tomorrow, and
I'll be taking printout of your comments with me.

Michael Prewett.

Steve Lusardi wrote:
Michael,
I am a builder and owner of a large steel boat. Insulation is absolutely
necessary in a steel hull. Corrosion is no problem on the outside, but ...

Very good comment indeed Steve. I'll also keep for later usage. Would your
recommandations also stand for an aluminum hull ? I know it has to be
insulated but i remember to have read that in order for adherence to the
aluminum, this later has to be etched and primed.

André

"Steve Lusardi" wrote in message
...
Michael,
I am a builder and owner of a large steel boat. Insulation is absolutely
necessary in a steel hull. Corrosion is no problem on the outside, but can
be a nightmare on the inside. Condensation is the culprit. The solution is
to seal the interior metal surfaces from exposure to air. This is
especially true for those surfaces that are hard to get to. That
requirement is best met by sprayed urethane foam on top of a quality paint
scheme. It has incredible adhesion qualities. It is fast to apply, but
extensive masking is required. It has some disadvantages, it is expensive.
It is not a closed cell foam, so it can absorb liquids over time, which
are not removable without gutting the foam. It outgases for a long time,
some of which can be harmful. When exposed to fire, the gasses created are
deadly. Once sprayed and cured, it should be painted with a waterbased
flame retardant paint. This will seal the foam countering the
disadvantages somewhat. Polystyrene foam is another choice. It is of the
closed cell variety, it is less expensive, it is not as messy as urethane
and it has a better R rating. It is harder to use because the adhesives
are slow curing. Volatile adhesives will dissolve the foam. Because of
this, it is slower to apply, as clamping is required. It does NOT seal the
steel from exposure to air, so the foam must be additionally sealed with
plastic sheet and outgassing in fire is also a problem as with urethane.
Another choice worth considering is rock wool. It is less expensive than
styrene, faster to install than styrene and can be purchased in a roll
with one side bonded with a plasticized aluminum foil which will aid in
sealing the metal surfaces from air as well as having a much better R
rating and an infra-red reflector. Probably the most endearing quality
Rockwool has is ease of maintenance and accessibility. It is easy to
remove and replace if it gets wet, as well as being fast to remove in an
emergency. One last point that is related is bilge protection, which is
also critical in steel hulls. Your insulation must not go much lower than
the waterline, typically only to the cabin sole. So where water
congregates requires special attention. There, you want to derust at well
as possible. then use a rust converter like a weak solution of phosphoric
acid or a commercial equivalent like Fertan, wash out well with water.
then an etching two part epoxy primer followed by a compatible bilge
paint. But, where water can sit, additionally spray that area with a
special marine paraffin based wax similar to Ziebart for cars. This
material never quite hardens and continually seals against water.
Completing these steps with just occasional maintenance will allow the
hull to remain viable for well over 100 years. One last note, commercial
ships and super yachts use Rockwool and the paraffin wax solutions almost
universally.
Steve



"Michael Prewett" wrote in message
...
I'm considering purchasing a small steel-hulled yacht, but she does not
have any insulation. I would imagine that the immediate problems in a
European summer will be excessive heat,condensation, and to a lesser
extent, noise. Retro-fitting insulation is an option, possibly in stages,
and I'm wondering whether anyone would have some views on this. My
initial thoughts tend toward the use of foam board, room permitting. (I
know that Alubat offer foam insulation as an option on their aluminium
boats, fitting boards between frames, but I don't know what material they
use - I would imagine that it is some form of polyurethane).

Michael Prewett

Andre,
Yes, it does, with caviats. Aluminum is very reactive in salt water. The
5000 AISI series is specifically intended for marine use. Do not use other
aluminum alloys. Do not electrically connect any other metal above or below
the waterline. Do use a cromate based primer. Do not believe any paint
company's assurances of performance from cromate free paints without making
tests yourself. I have seen many, many failures. In fact I have only seen
one truly successful aluminum yacht. It was built by an Australian Navel
Architect. It was 35' in length. He was so anal about mixing metals,
everything was aluminum, including the prop and shaft. I was there when he
took it out of the water on the Isle of Wight after 3 continuous years of
cruising. He had 10' long grass growing from the hull and absolutely NO
corrosion. So it is possible to be successful, but you will not acheive it
with out of the box components.
Steve

"André Langevin" wrote in message
...
Very good comment indeed Steve. I'll also keep for later usage. Would
your recommandations also stand for an aluminum hull ? I know it has to
be insulated but i remember to have read that in order for adherence to
the aluminum, this later has to be etched and primed.

André

"Steve Lusardi" wrote in message
...
Michael,
I am a builder and owner of a large steel boat. Insulation is absolutely
necessary in a steel hull. Corrosion is no problem on the outside, but
can be a nightmare on the inside. Condensation is the culprit. The
solution is to seal the interior metal surfaces from exposure to air.
This is especially true for those surfaces that are hard to get to. That
requirement is best met by sprayed urethane foam on top of a quality
paint scheme. It has incredible adhesion qualities. It is fast to apply,
but extensive masking is required. It has some disadvantages, it is
expensive. It is not a closed cell foam, so it can absorb liquids over
time, which are not removable without gutting the foam. It outgases for a
long time, some of which can be harmful. When exposed to fire, the gasses
created are deadly. Once sprayed and cured, it should be painted with a
waterbased flame retardant paint. This will seal the foam countering the
disadvantages somewhat. Polystyrene foam is another choice. It is of the
closed cell variety, it is less expensive, it is not as messy as urethane
and it has a better R rating. It is harder to use because the adhesives
are slow curing. Volatile adhesives will dissolve the foam. Because of
this, it is slower to apply, as clamping is required. It does NOT seal
the steel from exposure to air, so the foam must be additionally sealed
with plastic sheet and outgassing in fire is also a problem as with
urethane. Another choice worth considering is rock wool. It is less
expensive than styrene, faster to install than styrene and can be
purchased in a roll with one side bonded with a plasticized aluminum foil
which will aid in sealing the metal surfaces from air as well as having a
much better R rating and an infra-red reflector. Probably the most
endearing quality Rockwool has is ease of maintenance and accessibility.
It is easy to remove and replace if it gets wet, as well as being fast to
remove in an emergency. One last point that is related is bilge
protection, which is also critical in steel hulls. Your insulation must
not go much lower than the waterline, typically only to the cabin sole.
So where water congregates requires special attention. There, you want to
derust at well as possible. then use a rust converter like a weak
solution of phosphoric acid or a commercial equivalent like Fertan, wash
out well with water. then an etching two part epoxy primer followed by a
compatible bilge paint. But, where water can sit, additionally spray that
area with a special marine paraffin based wax similar to Ziebart for
cars. This material never quite hardens and continually seals against
water. Completing these steps with just occasional maintenance will allow
the hull to remain viable for well over 100 years. One last note,
commercial ships and super yachts use Rockwool and the paraffin wax
solutions almost universally.
Steve



"Michael Prewett" wrote in message
...
I'm considering purchasing a small steel-hulled yacht, but she does not
have any insulation. I would imagine that the immediate problems in a
European summer will be excessive heat,condensation, and to a lesser
extent, noise. Retro-fitting insulation is an option, possibly in
stages, and I'm wondering whether anyone would have some views on this.
My initial thoughts tend toward the use of foam board, room permitting.
(I know that Alubat offer foam insulation as an option on their
aluminium boats, fitting boards between frames, but I don't know what
material they use - I would imagine that it is some form of
polyurethane).

Michael Prewett

Hi Steve,

Thanks for your insight ! Altough my cruising ground is fresh water, i do
have an aluminum boat which turns 40 years old next year and it has no sign
of external or internal corrosion whatsoever. It was built from 5032-H34
alloy. I agree from my studies in chemistry that in salt water any
contact with another metal would create a cell and Al has very low
electronegativity. This is why i have 2 magnesium anodes instead of zinc.

The boat can be seen here; www.langevin.biz/marinette34

I am currently budgeting the cost for building a 45 feet aluminum sailboat.
Thus i have to take account into my budget that the aluminum hull has to be
primed inside. But your "rock wool" idea is very interesting also. It
could save me for priming the inside of the hull. Do you have any idea the
basis for comparing wool versus foam or another ? Is it a matter of price
or sound insulation ?

André

"Steve Lusardi" wrote in message
...
Andre,
Yes, it does, with caviats. Aluminum is very reactive in salt water. The
5000 AISI series is specifically intended for marine use. Do not use other
aluminum alloys. Do not electrically connect any other metal above or
below the waterline. Do use a cromate based primer. Do not believe any
paint company's assurances of performance from cromate free paints without
making tests yourself. I have seen many, many failures. In fact I have
only seen one truly successful aluminum yacht. It was built by an
Australian Navel Architect. It was 35' in length. He was so anal about
mixing metals, everything was aluminum, including the prop and shaft. I
was there when he took it out of the water on the Isle of Wight after 3
continuous years of cruising. He had 10' long grass growing from the hull
and absolutely NO corrosion. So it is possible to be successful, but you
will not acheive it with out of the box components.
Steve

"André Langevin" wrote in message
...
Very good comment indeed Steve. I'll also keep for later usage. Would
your recommandations also stand for an aluminum hull ? I know it has to
be insulated but i remember to have read that in order for adherence to
the aluminum, this later has to be etched and primed.

André

"Steve Lusardi" wrote in message
...
Michael,
I am a builder and owner of a large steel boat. Insulation is absolutely
necessary in a steel hull. Corrosion is no problem on the outside, but
can be a nightmare on the inside. Condensation is the culprit. The
solution is to seal the interior metal surfaces from exposure to air.
This is especially true for those surfaces that are hard to get to. That
requirement is best met by sprayed urethane foam on top of a quality
paint scheme. It has incredible adhesion qualities. It is fast to apply,
but extensive masking is required. It has some disadvantages, it is
expensive. It is not a closed cell foam, so it can absorb liquids over
time, which are not removable without gutting the foam. It outgases for
a long time, some of which can be harmful. When exposed to fire, the
gasses created are deadly. Once sprayed and cured, it should be painted
with a waterbased flame retardant paint. This will seal the foam
countering the disadvantages somewhat. Polystyrene foam is another
choice. It is of the closed cell variety, it is less expensive, it is
not as messy as urethane and it has a better R rating. It is harder to
use because the adhesives are slow curing. Volatile adhesives will
dissolve the foam. Because of this, it is slower to apply, as clamping
is required. It does NOT seal the steel from exposure to air, so the
foam must be additionally sealed with plastic sheet and outgassing in
fire is also a problem as with urethane. Another choice worth
considering is rock wool. It is less expensive than styrene, faster to
install than styrene and can be purchased in a roll with one side bonded
with a plasticized aluminum foil which will aid in sealing the metal
surfaces from air as well as having a much better R rating and an
infra-red reflector. Probably the most endearing quality Rockwool has is
ease of maintenance and accessibility. It is easy to remove and replace
if it gets wet, as well as being fast to remove in an emergency. One
last point that is related is bilge protection, which is also critical
in steel hulls. Your insulation must not go much lower than the
waterline, typically only to the cabin sole. So where water congregates
requires special attention. There, you want to derust at well as
possible. then use a rust converter like a weak solution of phosphoric
acid or a commercial equivalent like Fertan, wash out well with water.
then an etching two part epoxy primer followed by a compatible bilge
paint. But, where water can sit, additionally spray that area with a
special marine paraffin based wax similar to Ziebart for cars. This
material never quite hardens and continually seals against water.
Completing these steps with just occasional maintenance will allow the
hull to remain viable for well over 100 years. One last note, commercial
ships and super yachts use Rockwool and the paraffin wax solutions
almost universally.
Steve



"Michael Prewett" wrote in message
...
I'm considering purchasing a small steel-hulled yacht, but she does not
have any insulation. I would imagine that the immediate problems in a
European summer will be excessive heat,condensation, and to a lesser
extent, noise. Retro-fitting insulation is an option, possibly in
stages, and I'm wondering whether anyone would have some views on this.
My initial thoughts tend toward the use of foam board, room permitting.
(I know that Alubat offer foam insulation as an option on their
aluminium boats, fitting boards between frames, but I don't know what
material they use - I would imagine that it is some form of
polyurethane).

Michael Prewett

I agree that insulation is esential on the inside of any metal boat,
principally to stop condensation, but I would NOT use any of the foams
that giveoff formaldehyde when burned -- athis has been a real problem
in the RV world, and in a boat there is often nowhere to go to avoid
the deadly fumes.

Large yachts that must meet fire-proofing rules use rockwool to keep
the steel/aluminum from burning in a chemical or electrical fire,
which is a good idea. If one is not going to do that, the best thing
is to use a tightly-fitted sheet foam over a good coating system. The
sheet foam is removable when any welding has to be done.

Another product to consider (I have used it in a couple boats) is
Delta-T, made by Mascoat. This is a sprayable coating that also has
some sound-deadening qualities and is chemically inert and also won't
support combustion. http://www.deltacoat.com/

Cheers,

Michael Porter

www.mp-marine.com


"André Langevin" wrote:

Hi Steve,

Thanks for your insight ! Altough my cruising ground is fresh water, i do
have an aluminum boat which turns 40 years old next year and it has no sign
of external or internal corrosion whatsoever. It was built from 5032-H34
alloy. I agree from my studies in chemistry that in salt water any
contact with another metal would create a cell and Al has very low
electronegativity. This is why i have 2 magnesium anodes instead of zinc.

The boat can be seen here; www.langevin.biz/marinette34

I am currently budgeting the cost for building a 45 feet aluminum sailboat.
Thus i have to take account into my budget that the aluminum hull has to be
primed inside. But your "rock wool" idea is very interesting also. It
could save me for priming the inside of the hull. Do you have any idea the
basis for comparing wool versus foam or another ? Is it a matter of price
or sound insulation ?

André

"Steve Lusardi" wrote in message
...
Andre,
Yes, it does, with caviats. Aluminum is very reactive in salt water. The
5000 AISI series is specifically intended for marine use. Do not use other
aluminum alloys. Do not electrically connect any other metal above or
below the waterline. Do use a cromate based primer. Do not believe any
paint company's assurances of performance from cromate free paints without
making tests yourself. I have seen many, many failures. In fact I have
only seen one truly successful aluminum yacht. It was built by an
Australian Navel Architect. It was 35' in length. He was so anal about
mixing metals, everything was aluminum, including the prop and shaft. I
was there when he took it out of the water on the Isle of Wight after 3
continuous years of cruising. He had 10' long grass growing from the hull
and absolutely NO corrosion. So it is possible to be successful, but you
will not acheive it with out of the box components.
Steve

"André Langevin" wrote in message
...
Very good comment indeed Steve. I'll also keep for later usage. Would
your recommandations also stand for an aluminum hull ? I know it has to
be insulated but i remember to have read that in order for adherence to
the aluminum, this later has to be etched and primed.

André

"Steve Lusardi" wrote in message
...
Michael,
I am a builder and owner of a large steel boat. Insulation is absolutely
necessary in a steel hull. Corrosion is no problem on the outside, but
can be a nightmare on the inside. Condensation is the culprit. The
solution is to seal the interior metal surfaces from exposure to air.
This is especially true for those surfaces that are hard to get to. That
requirement is best met by sprayed urethane foam on top of a quality
paint scheme. It has incredible adhesion qualities. It is fast to apply,
but extensive masking is required. It has some disadvantages, it is
expensive. It is not a closed cell foam, so it can absorb liquids over
time, which are not removable without gutting the foam. It outgases for
a long time, some of which can be harmful. When exposed to fire, the
gasses created are deadly. Once sprayed and cured, it should be painted
with a waterbased flame retardant paint. This will seal the foam
countering the disadvantages somewhat. Polystyrene foam is another
choice. It is of the closed cell variety, it is less expensive, it is
not as messy as urethane and it has a better R rating. It is harder to
use because the adhesives are slow curing. Volatile adhesives will
dissolve the foam. Because of this, it is slower to apply, as clamping
is required. It does NOT seal the steel from exposure to air, so the
foam must be additionally sealed with plastic sheet and outgassing in
fire is also a problem as with urethane. Another choice worth
considering is rock wool. It is less expensive than styrene, faster to
install than styrene and can be purchased in a roll with one side bonded
with a plasticized aluminum foil which will aid in sealing the metal
surfaces from air as well as having a much better R rating and an
infra-red reflector. Probably the most endearing quality Rockwool has is
ease of maintenance and accessibility. It is easy to remove and replace
if it gets wet, as well as being fast to remove in an emergency. One
last point that is related is bilge protection, which is also critical
in steel hulls. Your insulation must not go much lower than the
waterline, typically only to the cabin sole. So where water congregates
requires special attention. There, you want to derust at well as
possible. then use a rust converter like a weak solution of phosphoric
acid or a commercial equivalent like Fertan, wash out well with water.
then an etching two part epoxy primer followed by a compatible bilge
paint. But, where water can sit, additionally spray that area with a
special marine paraffin based wax similar to Ziebart for cars. This
material never quite hardens and continually seals against water.
Completing these steps with just occasional maintenance will allow the
hull to remain viable for well over 100 years. One last note, commercial
ships and super yachts use Rockwool and the paraffin wax solutions
almost universally.
Steve



"Michael Prewett" wrote in message
...
I'm considering purchasing a small steel-hulled yacht, but she does not
have any insulation. I would imagine that the immediate problems in a
European summer will be excessive heat,condensation, and to a lesser
extent, noise. Retro-fitting insulation is an option, possibly in
stages, and I'm wondering whether anyone would have some views on this.
My initial thoughts tend toward the use of foam board, room permitting.
(I know that Alubat offer foam insulation as an option on their
aluminium boats, fitting boards between frames, but I don't know what
material they use - I would imagine that it is some form of
polyurethane).

Michael Prewett








--
Posted via a free Usenet account from http://www.teranews.com

I would hate to think of all the chemicals giving off by a modern boats
burning interior before the fire even gets to the spray foam. I think
any fumes given off by the foam burning will be the least of your
worries - if you are not out of the boat by then, then you probably are
not escaping at all. The myth of foam burning seems to persist - the
company who sprayed my vessel used a fire rated/retardant material.

Well, each to his own, but I have experienced burning urethane foam
once and was lucky to survive it. Before I put _any_ foam in a boat I
would want to see rigorous test data fromsomeone besides the salesman.

As to other chemicals, consider frayed insulation on a wire behind a
bulkhead that eventually sparks enough against the hull or another
wire to get things going. I've seen it happen,both in boats and in
houses.

Not for me, thanks.


"CS" wrote:

I would hate to think of all the chemicals giving off by a modern boats
burning interior before the fire even gets to the spray foam. I think
any fumes given off by the foam burning will be the least of your
worries - if you are not out of the boat by then, then you probably are
not escaping at all. The myth of foam burning seems to persist - the
company who sprayed my vessel used a fire rated/retardant material.
Michael Porter Naval Architect / Boatbuilder
mporter at mp-marine dot com
www.mp-marine.com

--
Posted via a free Usenet account from http://www.teranews.com