Thick foam around engine room ....

D

DLL

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We have thick foam, with a reflective "foil" on it. Recently it has fell down in a couple of places. After 20 years ... why now?

Today I looked it over and found the thick foam (about 1 to 1.5 inches thick) has a layer of heavy duty rubber inside it. I sprayed a high quality spray glue on it (3M) and it did not stick. I have some thin steel with holes in it, so I used wood screws to hold it in place.
In another spot I used decking type screws to hold it in place.

1. Any idea why this foam would just start falling off? I have not been well enough to take it out for a log run since Oct 2004. I know I have asked a couple of "off the wall" type questions...thanks so much for your patience. Any ideas on why the foam is just now "falling off" or what you would use to hold it on?
 
I would think that heat and age have caused the adhesive to give out or the same thing has caused the insulation to deteriorate.
 
not sure what 3m adhesive you used...there are special adhesives just for foam. Make sure the old adhesive is removed first. You need a clean dry suface to get a good bond.
 
I have similar foam on my boat and it too fell. I used a 3M spray adhesive (forget which one but is was rated for foam)

When you do it you must spray both surfaces and then press and hold together. The stuff I use is a contact based glue.
 
I found a glue specifying foam, sprayed the old foam, sprayed the surface, pressed it into place, then used metal trim to hold it in place until it is set.

BUT the reflective part is not sticking to the foam. I am looking for a way to ensure it does not fall again. I thought about the metal trim with long screws through it. That would keep the foam from being smashed down.

Is there another type of insulation we could use? My 3208TAs are pretty loud in the Salon.
The current foam has an almost solid layer in it. Fire proofing?
 
There are three things that I would suggest you do:

Google insulation hangers and find the ones that look like perforated metal with a nail protruding from the center. Buy some of those along with the necessary buttons/washers that fit on the nail. Buy a good spray foam adhesive. Buy some high strength metal tape from Home Depot or a plumbing supply. Make sure it's wide. Buy a good adhesive like 3M 5200 or two part epoxy.

As you can tell, I like to spend money.

Now that we have the necessary supplies, it's time to start.

Bond the insulation hangers to the underlying substrate and let the adhesive cure enough so that it's not going to release once you move onto the next step. Spray a sufficient amount of adhesive onto the foam and underlying substrate and let it get tacky. Bond the insulation to the underlying substrate under moderate pressure. When you're doing this, the nails will be forced through the insulation. Place a cap/washer onto the nails. You might have to trim the nails, depending on their length. Finish off the installation by covering the washers/caps with the foil tape. This should solve all your problems.

Bob
 
I was thinking of doing it just the opposite of you. Clean the "ceiling" in the bilge area.
Then spray the foam and wood. Press it up to the wood, THEN use an expanded metal type device to "hold" the foam in place.

I have been wondering about adding MORE sound proofing. Just a thought.
 
The method that I described is an accepted industry standard for bonding that type of insulation to an underlying substrate. You can use whatever method you like.

If you decide to screw through the foam, I would use a large fender washer on the screw and still use the foil tape to cover that hanger.

Here are three web sites you might want to visit:
www.soundown.com
www.soundprooffoam.com
www.cyber-bridge-marine.com

Look at their insulation/soundproofing products and suggested methods of installation.

Bob
 
Do you use a special kind of foam? I looked at the website soundprooffoam and it looks like the have a very easy solution called ultra barrier plus which has an adhesive side and is "ideal for marine applications and engine compartments" but it's $150 for a 4 ft by 4 ft piece.
 
I hate to be the bearer of bad news, but I know exactly why it is falling down. The foam has reached the end of its useful lifespan and is breaking down. You can try to re-glue it for now, or use mechanical hangers of some type, but it the foam is going to continue to break down, crumble and when it gets really bad will start to turn into this gooey tar like mess that goes everywhere, is easy to track and hard to get out of whatever it is on (surprisingly laundry detergent concentrated strength in hot water on a rag worked the best, better than solvents, simple green, etc..).

My boat is an 80, I did mine two years ago (still have the lazarette to do). It was a big job and big mess. Do it now when the sheets come down relatively intact.

The insulation is diesel rated insulation. That hard middle layer is a lead impregnated tar like material that helps the insulating panel do its sound insulating job. You don't find the lead layer in gas rated foam. I don't know why exactly without guessing.

Sorry to be the bearer of bad news, but I'm confident that what you are seeing is typical for the material/age. Also, it cost me about a boat unit in materials cost to redo my engine room with new material of the same type. I put mine up with contact cement and a few hangers in places that needed them.
 
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