Insulating Triton #680

bcooke · Post by **bcooke** » Tue Feb 28, 2006 2:12 pm

I got a PM message on the forum about my plans for insulating my boat and after elaborating on my plans I figured I might as well post it for others to comment/critique.

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I wasn't sure if I really wanted to tackle insulation but now, while the interior is stripped down, is the only time to do it.

I am going with a product called "Armacell AP" made by the company "Armaflex". It is a closed cell foam designed as a marine insulation. It is very flexible, water and fire resistant.

Based on the sales rep's suggestion I am going with a 1 inch thickness. The charts seem to indicate 3/4" would be sufficient but what the heck, more is better, right?

This stuff is attached with a proprietary contact cement. I think most any contact cement would work but naturally the company won't stand behind their product if something else is used. A gallon of the cement costs $30 so it seemed reasonable to go with it.

I am fighting the cold weather which is going to restrict my progress but basically, I am glassing in the tank supports, bulkheads and anything else that needs to be attached directly to the hull. The insulation is pretty soft and spongy so I will be lining the interior spaces where stored items would contact the insulation with 1/4" plywood. In order to secure the plywood I need to glass in a few strategically placed wooden blocks against the hull to give me something to screw down to. The screws and more contact cement will secure the panels covering the insulation.

It is a pain in the neck but if I don't do it now then it will never happen. Early and late season water temperatures around me can be in the 40's and 50's which can really add a chill to the cabin. Those foggy Maine days and periods of otherwise high humidity can also lead to an awful lot of hull "sweating" and general cabin dampness. Both of these issues will be improved a lot by the insulation and with the small wood/coal stove installed, I expect the boat to stay pretty comfortable even through a cruise into the Canadian maritime provinces.

The plan is to insulate the entire cabin area of the hull including the underside of the cabin sole. I don't intend to insulate the underside of the deck because it would be too much of a pain and I am telling myself that the coring provides me with a limited but acceptable insulation factor. I could be wrong about that but I am NOT going to go to that much trouble. I will sail to points south first. This will cover the entire cabin area from the V-berth (and maybe aft side of the chain locker - not sure yet- it would be a pain and I am not sure if it would be productive) to the aft end of the galley area. I am fitting proper bulkheads to the sort-of bulkheads found under the bridge deck and will insulate forward of there. Aft of the bridge deck, the "engine room", the bilge, and the chain locker areas will not be insulated from the hull.

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That's it. All comments and critiques welcomed, though I reserve the right to totally ignore anything I read :-)

When I get some decent pictures I will post them here as well.

-Britton

A30_John · Post by **A30_John** » Tue Feb 28, 2006 7:34 pm

Britton,

I'm very interested in what you're doing here. I've been thinking about doing something similar next winter. Here's an observation and a few questions.

In addition to keeping the cabin warmer when you run the heat on cold days, the insulation may help keep your cabin cooler on hot days. With that in mind, you might want to consider doing under the decks too, since that can be a significant heat generation area. It does, however, raise the question of how well the contact cement will hold once it gets heated up. Even the sun beating down on the topsides in the late afternoon might heat the sides up pretty good too. Have you tried a test sample to see what might happen?

I'll be interested to hear how much locker space is taken up by the insulation and plywood backing. It could add up. Depending on how far down you do this, another consideration could be the weight of the plywood. Another possibility might be protective slats made of thin wood.

Are you insulating below the waterline as far down as the cabin sole?

Are you insulating the cabin ceiling?

Are you insulating the head area and v-berth as well? Ceilings in these areas?

I think you'll be very pleased with it when you're done. It would definitely make my boat a lot more pleasant. It would greatly assist my kerosene cabin heater in keeping the main cabin warm and keep out the drippy condensation. I think the acoustical insulation would also be welcome.

Enjoy the project!

Tony · Post by **Tony** » Thu Mar 02, 2006 11:45 pm

When we lived aboard our Harstad 31, "Solace," in the process of demolition I removed the aging and damaged polystyrene from the underside of the decks and the cabin ceiling. After that, the temperature increased almost 5 degrees on an average day and almost 8 degrees on a very hot sunny day, so that extra effort could pay off for you if you decide to do these areas as well. In our case there was only ~1" on the cabin ceiling and probably 1/2" under the decks.

CharlieJ · Post by **CharlieJ** » Fri Mar 03, 2006 10:11 am

Can make this observation from experience on Tehani.

The decks are cored, the cabin sides and overhead are not- that is solid glass. We experience NO condensation under the side decks or under the fore deck- we get LOTS of condensation on the underside of the cabin overhead and on the sides. Behind our ceilings in the fore cabin and along the tops of the settee backs I insulated- no problems there.

Wish I could figure something to use to insulate the cabin sides and overhead that A) looked good B) didn't steal headroom and C) would fit to the big curves of the cabin top to side transition. That's really the tough part :)

That's a tough order and I'm still wiping down and searching.

A30_John · Post by **A30_John** » Fri Mar 03, 2006 12:04 pm

Wish I could figure something to use to insulate the cabin sides and overhead that A) looked good B) didn't steal headroom and C) would fit to the big curves of the cabin top to side transition. That's really the tough part :)

Charlie, you might want to consider cork. It meets at least two of your three requirements. A PO of an earlier boat I owned used it and I liked it a lot.

http://www.corkstore.com/compass/servle ... onid=login

bcooke · Post by **bcooke** » Fri Mar 03, 2006 8:05 pm

In addition to keeping the cabin warmer when you run the heat on cold days the insulation may help keep your cabin cooler on hot days

Yes, I had thought of that. Since I am leaning towards a dark hull color the insulation should make a tropical cruise much more pleasant as well. As for insulating the ceiling though... it would be nice but the workload is considerably more. I might leave that for a future time when I am bored and run out of projects. The balsa coring does provide a little insulation and I think I will just live with that for now.

As you (John) pointed out, the insulation does take up valuable space. I think I can live with the reduction of space against the hull. Visually I am not sure how insulating under the ceiling would go over. Maybe under the side decks if I have material left over.

Wish I could figure something to use to insulate the cabin sides and overhead that A) looked good B) didn't steal headroom and C) would fit to the big curves of the cabin top to side transition. That's really the tough part :)

My sentiments exactly.

I haven't done any tests. This stuff is designed for marine applications so I am going to assume it can handle basic conditions found on the boat.

Yes, I will be insulating behind and below the settees down to and including the sole. Last summer I jumped out of the V-berth one morning in my bare.... feet ... and my toes got so cold (water temps in the 40's so the sole was about the same) that I swore right there I would insulate the cabin sole as well. As for the plywood lining. Maybe I should clarify that and call it a veneer or something. I am thinking of something pretty thin, like 1/8" or so just to spread the load and protect the foam from any points of pressure. Slats might work fine. Whatever is easiest. This will all be storage space and probably just painted. I don't need anything too pretty here.

I will be including the forward areas in the job. The forward areas should be pretty easy since I have tanks over most of the hull in the V-berth area so I can just stick down the insulation and mount the tanks over it (on proper tank supports of course - not directly on the insulation). Installation of the insulation itself should be pretty simple. It is the protective covering over it that will take the time. And before I lay down the insulation I have to have all the interior parts that attach to the hull in place.

I need 40 degrees for the contact cement. I need 50 degrees for the epoxy taping that will hold the bulkheads/tank supports/ and other interior parts. That means I have a month or two before I can post anything but I will as soon as I can.

-Britton

bcooke · Post by **bcooke** » Fri Mar 03, 2006 8:06 pm

repeated message deleted.

bcooke · Post by **bcooke** » Fri Mar 03, 2006 8:07 pm

repeated messaged deleted

bcooke · Post by **bcooke** » Fri Mar 03, 2006 8:08 pm

repeated message deleted.

I am not trying to be funny. I can't see any way to make my post go away permanently so I am just shortening them with the edit function.

-Britton

CharlieJ · Post by **CharlieJ** » Fri Mar 03, 2006 10:31 pm

Britton??? You stuttered? Grin.

Just to be real picky here- the "ceiling" in a boat is NOT up over your head. The ceiling is strips of wood (or other stuff) that runs along the inside of the hull sides.

Same way that understanding that "topsides" is the sides of a hull from the deck edge to the water line.

Just , as I said , being a little picky, but terminology DOES help understanding, particularly since we can't spaek face to face..

bcooke · Post by **bcooke** » Fri Mar 03, 2006 11:07 pm

I didn't stutter. The Forum Monster did. I only hit the button once. I promise.

Are you insulating the cabin ceiling?

Just to be real picky here- the "ceiling" in a boat is NOT up over your head. The ceiling is strips of wood (or other stuff) that runs along the inside of the hull sides.

Well, yes, but I don't have strips of wood that run along the hull sides so I took the question to mean the top of the cabin.

But point taken nonetheless :-)

-Britton

bcooke · Post by **bcooke** » Fri Mar 03, 2006 11:15 pm

Oh, and Charlie,

Tehani has a cored deck and a solid cabin top? Interesting.

Mine is cored and cored again.

-Britton

Post by **Tim** » Sat Mar 04, 2006 6:57 am

bcooke wrote:This stuff is designed for marine applications so I am going to assume it can handle basic conditions found on the boat.

Dangerous, very dangerous! hehe

CharlieJ wrote:Just to be real picky here- the "ceiling" in a boat is NOT up over your head. The ceiling is strips of wood (or other stuff) that runs along the inside of the hull sides.

Same way that understanding that "topsides" is the sides of a hull from the deck edge to the water line.

Just , as I said , being a little picky, but terminology DOES help understanding, particularly since we can't spaek face to face..

Thank you! The proper terminology DOES matter, all the more so in this age of people seemingly not caring about the sanctity of proper language, both spoken and written.

bcooke · Post by **bcooke** » Sat Mar 04, 2006 9:19 am

Dangerous, very dangerous! hehe

It is the only way to truly live :-)

Maybe I was too short in my last reply. (it was past my bedtime)

Terminology is important; especially when the written word is the only thing we have to work with. In retrospect I should have made a query rather than risk confusing the issue by going along with ad hoc terminology.

When I think about it, words are really a poor form of communication and the technique is fraught with hazards.

-Britton

CharlieJ · Post by **CharlieJ** » Sat Mar 04, 2006 9:58 am

I'm glad others agree that terminology is important. It makes for more precision at any rate, particularly when reading on a screen rather than sitting in the salon (which SHOULD be saloon, but thats an old fashioned English term *grin) face to face and being able to use hand gestures to clarify meanings.

And yes- Tehani is cored on the under decks from the anchor locker aft to the bridge deck. But the cabin is solid from the turn of the deck up, forecabin and main. All around the top is probably 1/4 to 3/8 in solid glass.

The companionway USED to be 32 inches square, but when we rebuilt her I reduced that gaping hole to a more seamanly 24 inch square, and added a proper seahood. After many many weeks of study, through every book I had and every book I could find in the library, I FINALLY was given "Yacht Joinery and Fittings" by Mike Saunders - another English book. In there I found clear, concise drawings of a seahood and slide that was RIGHT. So I used it.

JetStream · Post by **JetStream** » Sat Mar 04, 2006 12:31 pm

Charlie-
Thanks for the heads up on the Mike Saunders book. After your first post on it, I found a used copy on Amazon for very cheap. It is really a very helpful and practical book.

CharlieJ · Post by **CharlieJ** » Sat Mar 04, 2006 2:17 pm

Glad you liked it Bruce.

I have a BUNCH of boat building and rebuilding books, since I build boats for money - not enough money, but lots of fun *grin*

I've been somewhat disappointed in many of what are otherwise highly touted books. For example, try finding something in writing on installing a heel fitting on a rudder such as the ones on the Triton and Meridian which sit in a heavy fitting on the rear of the hull.

Chapelles is good IF you are building a traditional wooden boat, but there's LOTS of stuff he doesn't cover.

I also like Spurr's "Upgrading the Cruising Sailboat" written about a Triton upgrade, but very useful. But again- many gaps, which in this case is understandable since he's concentrating on one specific boat.

Fred Bingham's book on yacht carpentry I found, shall we say, underwhelming. I was frankly quite disappointed in the book.. He skims a lot of subject, but then omits the in depth stuff.

Casey's book is good, but again he omits many things that should be covered.

Many more on the list but you get the idea. You just have to search through what ever you can find if you are interested in doing anything the least bit out of the ordinary - out of the ordinary in TODAY'S world that is.

Can be quite frustrating, and it's always nice to find a jewel *grin*

A30_John · Post by **A30_John** » Sat Mar 04, 2006 2:59 pm

Just to be real picky here- the "ceiling" in a boat is NOT up over your head. The ceiling is strips of wood (or other stuff) that runs along the inside of the hull sides.

So what do you call the part over your head in the cabin.

CharlieJ · Post by **CharlieJ** » Sat Mar 04, 2006 3:27 pm

LOL- I call it "the overhead" which is what I learned to call it in my uncle's yacht club.

That's Uncle Sam's Navy by the way. *grin*

A30_John · Post by **A30_John** » Sat Mar 04, 2006 3:32 pm

Thanks - overhead it will be!

BTW Charlie J, you might want to seriously consider cork for your overhead. If you're primary consideration is condensation prevention, it works well because it takes up so little room. If you're looking to do some serious insulating, Britton's solution looks good.

CharlieJ · Post by **CharlieJ** » Sat Mar 04, 2006 4:47 pm

discussed cork with my artist wife- who by the way, did all the painting on the interior of the boat.

I got a flat "NO". She claims she'd rather live with the occasional condensation until we find something that will "go away" visually up there.

I think we'll be mopping condensation for a while *grin*

A30_John · Post by **A30_John** » Sat Mar 04, 2006 4:54 pm

Your wife can paint the cork..! :-)

Jedediah · Post by **Jedediah** » Mon Mar 06, 2006 4:43 pm

Britton,
Some questions because I'm also going through this at the moment, except on a Cal 29 in Seattle on a cold lake. How are your fiberglassed blocks turning out? This is the biggest problem I've found with the Armaflex since under point loading the foam degrades. Here is my solution:

Take a 1"*2" oak board and chop it into 1.5" squares 3/4" thick (I'm using 3/4" thick foam due to cost per sqft). Use epoxy of choice but not the quick stuff out of the tubes (it pulls apart under tension after time), I've found PC-11 to work well so far and doesn't run down walls. Glueing these every ~12-16 inches seems to work. I bought some of the adhesive but have yet to use it since the wood skin holds the insulation in place. Is your solution easier?

As for covering I went with door skins since they are thinner, lighter, and more flexible. The birch isn't very thick and as a result you can't sand it. However, what are you doing on the curved areas? At lease Cal 29's have them... Any solutions there? I'm debating about using carpeting or something that can handle the serious compound curves at the top of the cabin. What's your solution there?

A word of advice for price and R value is on large flat surfaces is to use extruded polystyrene (blue or pink board). Lowes here has it in 1" thick wich is much more flexible than 2" I found out the very hard way. It also will have an R value of 5 vs 3.8 for 1" Armaflex AP. However, it will produce some wonderous vapors when burned that Armaflex NP (or was it NF) doesn't, not sure about what Armaflex AP gives off--hoping to never find out. Both extruded (not expanded) polystyrene and Armaflex AP do not absorb water like most other insulations and seem the only serious long-term solution for insulation, but maybe I'm mistaken.

And if you want any picts let me know and I'll send them over (gerstlej_at_u.washington.edu)

bcooke · Post by **bcooke** » Tue Mar 07, 2006 12:55 am

How are your fiberglassed blocks turning out?

Temperatures here are in the 20's (Farenheit) so I am not glassing anything at the moment. When I DO put the blocks in I will probably secure them with a layer cloth. That way they will NEVER come loose.

Door skins is a good option I hadn't thought of. Like you say, the Armaflex is pretty soft stuff and deforms easily. Lucky for me, the hardest curve in the hull is about where the settee so there is a natural break there and I can go with two straighter panel above and below the settee attachment point. I think worst cast option, I will glass in blocks at the top middle and bottom of the area in question and draw the plywood/skin/veneer/whatever to the blocks. I would like to have a tight glued contact between the inner surface of the insulation and the inner covering but I am willing to sacrifice that if it gets too hard. I don't expect too much condensation on the inner surface of the insulation so a small air gap is acceptable.

Something to keep in mind, for me at least, is that there is a limit to how "perfect" I can make this installation. I am working with a 40 year old Triton and I need to work within its limitations. I believe there will always be a better or more perfect way to do this insulation job but I don't want or need to have the best insulated/warmest boat on the water. I just need enough to reduce the sweating to reasonable levels and stay as warm as is reasonably possible. If I was going to the Arctic I might strive a little harder or possibly start with a boat more condusive to such an adventure.

I'm debating about using carpeting or something that can handle the serious compound curves at the top of the cabin. What's your solution there?

My solution is to NOT do the cabin top. Too much trouble with no easy solution. Carpeting is an option but not one I am willing to pursue at the moment. If it gets so cold that I really NEED insulation on the cabin top I think an easier solution is to sail towards the equator. I enjoy reading about people wintering in the Antarctic but I have no wish to join them! :-)

According the the Armaflex sales rep. The difference between AP and ... the other one that I can't remember... is that one smokes more but the smoke is less toxic and the other smokes less and is more toxic. The rep seemed to suggest there there wasn't really much difference between them but the "other one" was designed specifically to meet U.S. Navy requirements for smoke/toxicity.

-Britton

bcooke · Post by **bcooke** » Tue Mar 07, 2006 1:03 am

Another thought I just had about getting the inner surface to follow the curved surface of the insulation...

If the inner panels are cut tight to the limits of the working area, a curve will be forced into the panel. As the panel tries to straighten it will lengthen its linear dimension which will be restricted by the confines of the working space. Of course getting this theory to work in practice means cutting the panels to pretty tight tolerances.

I should know how this is going to go much better in a month or so when the temps get into the reasonable range.

-Britton

Rachel · Post by **Rachel** » Tue Mar 07, 2006 1:22 am

Now that Jedediah mentioned extruded polystyrene, I'm hoping Charlie J. will pipe in with a photo or two of Tehani's forepeak. He and Laura used polyisocyanurate sheets (I believe - "rigid" insluation, in any case) between wooden strips, and then covered the lot with varnished ash ceiling. I think they may have insulated part of the saloon, too.

(Actually, he may have posted a photo of it when he was talking about the overall project of the boat.)

At any rate, it's always great to see how someone else did a particular project; and in their case it turned out really nice. Charlie? :-)

--- R.

Jedediah · Post by **Jedediah** » Tue Mar 07, 2006 4:44 am

I've found that cutting the panels to close tolerances only partly works. If the points forcing the curves are foam, the foam will deform or be cut through in time. And for my case, many of those points almost have to be foam. The real issue is I have a hard time putting a 6" radius on a panel that also has a bend in the other direction (a Cal 29 problem it sounds like).

An inner air gap has not been a problem with my installation (what parts of the boat I've done so far) as long as there is no air flow through that space. With Armaflex I've found it easy enough to cut an extra 1/2" too big and use that as a seal around the edge fixing this problem. With the extruded polystyrene I started with, that is a different story. Spray polyurethane? This, along with easy and cleanliness of cutting, are why I've found Armaflex to be much easier to work with.

Thank you for the reality check on realising things can only be so good with the installation. I personally like the tropic solution to all of this.