Spray foam insulation

Can anyone tell me why one couldn't use Closed cell spray foam for insulating the sidewalls of a trawler. Closed cell is the foam Boston Whaler uses in their boats to keep them from sinking

Greetings,
Welcome aboard.

bankerboy1 said:

Can anyone tell me why one couldn't use Closed cell spray foam for insulating the sidewalls of a trawler. Closed cell is the foam Boston Whaler uses in their boats to keep them from sinking

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Makes good sense to spray foam the ceilings to stop condensation dripping on your head; but it's better to just push sheets of insulation between the frames on the vertical surfaces, then you can remove them to make alterations or weld on a steel boat.

All the condensation drips run down vertical surfaces and go into the bilge causing no problems.

Thank you for your reply, I was thinking more of the sidewalls and the ceiling so I could full time, surviving the winter months in the Baltimore Harbor. If the closed cell spray foam can be used, I will install 1 inch PVC tubes here and there in case I want to pull wires later on.

Before you try spraying the closed cell foam over head, practice on a horizontal surface and protect the surrounding area. The stuff sticks like super glue. I have always had a hard time (like never) getting a smooth finished surface. I haven't been able to control the application vs the expansion rate of the foam. I've tried smoothing/trimming it later, with an electric knife, with mixed success.

Overhead, since it should be a flat surface, I'd try what RustyB suggested, using sheets.

The only disadvantage that I can think of is if you need to access for visual inspection and/or repairs. I recently insulated the Ulysses on a cabin rebuild and went with both a reflective sheet and insulation mats for the same reasons posted by Peter along with future painting as will be necessary sometime.

bankerboy1 said:

Thank you for your reply, I was thinking more of the sidewalls and the ceiling so I could full time, surviving the winter months in the Baltimore Harbor. If the closed cell spray foam can be used, I will install 1 inch PVC tubes here and there in case I want to pull wires later on.

Click to expand...

Spray foam is amazing, it's really does it a fantastic job.

But....
Several years down the road when you may need to refurbish the interior surfaces removing the foam is a total nightmare; in fact virtually impossible.

I pushed insulation between the frames on my ceilings and it was a disaster; I get constant drips in the winter, and funnily enough it's always exactly over my head!

My advice is to use different methods of insulation on different surfaces.

Anyone ever use large bubble wrap?

It's not great insulation, but does not get soggy and easy to remove.

As we write, I am about to embark on a similar insulating adventure. I have put this off for some time, but now is the time.

It is really more about controlling random air flow around the hull. I have set up air dryers and computer fans to keep the boat dry(er) inside. The last rain blast we had left a lot of condensation (molding) inside. I had also installed an engine room blower last summer to evacuate the heat and fumes after shutdown. The blower expels into the lazerette to aid in keeping it dryer, where it is then vented up and out in the cockpit.

I want to be able to control the air flow through the boat from cabin aft to bow berth, through the engine room and out to the lazerette.
I plan to stuff some large bubble wrap in various gaps along the hull to control the air flow direction to hopefully reduce the current randomness to get an efficient drying effect. Maybe I am nuts, but easy enough to try.

Any thoughts on this?

Greetings,
Mr. DJ. Hmmm...warm air from the ER to a cool lazerette? Sounds like a good formula for condensation in the lazerette to me. One can buy this foil covered stuff:

Computer fans may not move enough air. We use 5 or 6 of these not necessarily for keeping the boat direr, but for large volume air movement. Mold likes stagnant air.

RT F,

I use the shiny bubble foil as well.
I need the large bubble to stuff in large gaps that are impossible to reach between the lazerette and midships to prevent the air pushed into the lazerette from recirculating back through the engine room again. Similar problem around the forward bulkhead.

bankerboy1 said:

Can anyone tell me why one couldn't use Closed cell spray foam for insulating the sidewalls of a trawler. Closed cell is the foam Boston Whaler uses in their boats to keep them from sinking

Click to expand...

The only downsides are the difficulty of removal and the fact that when spray foam burns, it gives off cyanide gas. To avoid those problems I lined Delfin with 1/4" acoustical cork, simply glued on. Never a drop of condensation.

Grade QuietCork™ Rolls | Jelinek Cork

Hmm,

Cork sounds interesting. How well does it hold up and do you paint it or leave natural?

Delta_JimS said:

Hmm,

Cork sounds interesting. How well does it hold up and do you paint it or leave natural?

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I used the industrial product that is glued together with a polyurethane binder, so it lasts indefinitely. We just glued it over the painted metal throughout the interior for condensation control and sound deadening, which is what it is designed for. No paint, but 2" fiberglass batts were put over the cork. Jelinek does make products designed for finish surfaces but I haven't used those.

Foil covered bubbley stuff is good, noticed a major difference in temp. control. If over steel though prevent the Alum. from contacting the steel.

At some point as you go from the heated cabin air to the hull the water vapor will become a liquid.

How to figure where how the water can be drained is the hard part .

With limited thickness ALL INSULATION has limited value.

Sometimes simply burning a bit more fuel is a better answer.

Wool rugs on the floor will be a huge help , I prefer a top layer of bathroom carpet as it can be machine washed in a big laundry machine.

Guests will frequently not want to remove boots , so visitors will bring mud and mess

The window glass is a total heat looser , .look up Warm Shades a simple solution.

I just did a Gulfstar with 1/2 inch polyethylene sheets glued in or press fit. It is available in thicknesses from 1/4 to 2" comes in rolls or 24x54" sheets. Very flexible and seems to work very well both as sound deadening and for warmth. This is available with a reflective foil skin as well. Used as roofing underlayment, packing, insulation and under floating manufactured wood floors. Seems to be working very well.

Just a caveat concerning bubble wrap: the adhesive tape that's used to attach sheets together will fail in the damp marine environment.

Here's what happened to mine after about 10 years; the new bit of tape is just a tempory repair.