Inject a deck

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mike66

mike66

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Susan Helena
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Pardon if this has been covered, but has anyone had experience with inject a deck foam? I've been on a two year project of basically drilling out my teak deck screws to 1/2", letting the deck dry under cover six months over the winter, and injecting epoxy. It has resulted in a solid deck. I still have a couple of areas on the side nd aft decks of several square feet. This product supposedly doesn't mind if the wood core is wet. So, looking for advice/experiences. Thanks.
 
mike66 said:
Pardon if this has been covered, but has anyone had experience with inject a deck foam? I've been on a two year project of basically drilling out my teak deck screws to 1/2", letting the deck dry under cover six months over the winter, and injecting epoxy. It has resulted in a solid deck. I still have a couple of areas on the side nd aft decks of several square feet. This product supposedly doesn't mind if the wood core is wet. So, looking for advice/experiences. Thanks.
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I’ve only read about it and seen the videos. I assume the stuff is like what they inject in basement wall cracks that expands slightly and doesn’t mind the moisture
 
Do you have a link so we know we're talking about the same product? I can think of an application at home if it's good.
 
While the foam products will indeed cure in wet conditions and underwater, it does not remove water or stop the resultant rot in the core.
I would only use it as a temporary fix until the problem can be corrected,
There ain’t no easy way out!
 
I had someone do an epoxy treatment for damp problems in a house, it is to replace a failed dampcourse or create one where there was none. The wall was drilled and multiple injectors left in place at least overnight, attached to a pressurized pump system. The material injected was very thin, it distributed itself into the bricks over time. Got rid of the inner city cockroaches too.
Not sure it would work by single injection into a pre-drilled deck area, but the OP`s experience says it does. Anything to avoid a massive rip out the deck job.
 
If the foam purpose is insulation , heat or noise it should work.

If it is to rebuild a failed core the usual deck material is far stronger than what comes from a spray can.
 
I think injectadeck uses 12lb density foam, that stuff is like concrete after curing.

I would be more worried about over expansion. The one website I saw using it had the guy weighting the deck down as it cured. With it expanding 6x the liquid volume it wouldnt be hard to split a deck. Id stick with the epoxy method.

"Once expansion starts remove plug or finger, you can step on it to move it around.and prevent bulging. 4 minutes later, Bad bulge? jump up and down on it within the first 10 miinutes uncured, it will flatten, also over time bulging goes down.."

Instructions
 
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I used expanding foam many years in boat building and repair. The foam is 2 part, epoxy like, that expands and cures within minutes. It comes in various weights that supports a deck and lighter weight for wall insulation. Stronger foam expands less but supports more weight. Because it expands, too much foam injected will cause a light deck to bow upward or downward depending on the strength of the containing structure. It can be mixed and poured or sprayed with specialized equipment. It doesn't matter to the foam if surfaces are wet as far as curing. But I would dry the wet areas.
I used the foam mostly in commercial steel boat construction where it was sprayed on the hull and bulkheads and then fiberglassed over. But I also used the light weight foam below the floor in small powerboats for support and creating spaces that couldn't flood even with a hull breach. In commercial fishing boats the foam could be as much as 2' thick for fish hold insulation and 4-6" for cabins. All sprayed.
 
Repairing Wood Rot. Window Log Cabin Epoxy Repair 603.435.7199 -
Scroll to the bottom for an interesting take on rot control in wood. I did infuse my deck with antifreeze before allowing it to dry for six months. Don't know how well the epoxy bonded to anything, but the decks are solid. Maybe I won't get freeze damage?
We are looking at a leaky trawler here that isn't worth to me the expense of deck replacement the proper way. If this is a ten year Band-Aid then I'm happy.
 
I also would stick with the epoxy injection. At least the epoxy is a known quantity.
 
I read the instructions. Not impressed with the quality of the instructions, some misspelled words and strange wording. If they cannot get the instructions correct, what else is wrong. Maybe this is a great product, it just has a questionable look. Personally I would not put this into the deck of my boat. How much work will it be to remove if needed? How much history is there on this product? Is there anyone that can say they actually used this? Maybe I am too picky, but my boat is my baby and I want to know what I am doing to it. Stand on the bumps if needed... really? Oh BTW you have 10 seconds or so to stand on the bumps...
 
kapnd said:
While the foam products will indeed cure in wet conditions and underwater, it does not remove water or stop the resultant rot in the core.
I would only use it as a temporary fix until the problem can be corrected,
There ain’t no easy way out!
Click to expand...

My thoughts EXACTLY! There ain't no easy way...
You've got to get the existing water out. It took years for it to get in there and it wont come out on it's own.
Here's a couple of pictures of the attempted repairs by the PO of our boat. You can clearly see the holes drilled for the resin to be poured in on the heap of decking debris removed for our repair. All it did was make a bigger mess for the correct repair job.
 

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A long time ago, we used 2 part foam to fill steel channels in the body of a rally car. It required cutting holes,quickly pouring in the mixed liquids, in a guessed at volume, and waiting.The extent the foam spread could be gauged by the heat it put out,and if foam exited at any holes,existing or drilled. It was imprecise, there was a worry about putting too much into a confined area, with deformation risks, etc. But we got away with it, and I think it added some strength and rigidity.
My boat has a foam deck core, so the idea makes some sense, but shooting unregulated volumes of foam liquid into a wet area of rotting wood doesn`t make a lot of sense to me.
 
Not a perfect way to repair a deck, but as good as many boaters have the talent to.

Also not as bad as some make it sound having worked with 2 part foam.

Yes, out think the instructions a bit and it may work out fine.

Wet decks can be repaired and dried from underneath on some boats..
 
mike66 said:
We are looking at a leaky trawler here that isn't worth to me the expense of deck replacement the proper way. If this is a ten year Band-Aid then I'm happy.
Click to expand...

I think you have answered your own question. Sounds like you have found a solution that works for you. Personally I think the deck forms part of the structural integrity of the boat and a rotten core destroys the bond between layers leaving the top thin layer unsupported. You end up with a springy deck and spreading rot.

I don't think any polymer or foam is going to permeate far, it simply fills in the space between the soggy core and the top layer restoring some firmness to the deck. All is solved. That is until the rotten core continues to dissolve leaving a new gap so the foam is no longer supported leading to a springy deck again.

The structural integrity of the boat no longer exists. Wouldn't want to take the boat past Brenton Point on a rough day with outgoing tide.
 
If the boat is a keeper , there is a plan B.

Grind the exposed deck to bare glass and use a thickened epoxy to lay a deck of actual structural foam.

It can be done in pieces and plastic bags with sand will hold the core to the old deck surface.When enough area is covered the top layer of deck can be glassed on using polly resin which is far cheaper.

If a thicker than ordinary deck layer is selected and the proper foam used a teak overlay can once again be screwed down.

It doesn't look as yachty ,but Treadmaster would be a good selection if the boat is going out to blue water..
 
FF said:
If the boat is a keeper , there is a plan B.

Grind the exposed deck to bare glass and use a thickened epoxy to lay a deck of actual structural foam.

It can be done in pieces and plastic bags with sand will hold the core to the old deck surface.When enough area is covered the top layer of deck can be glassed on using polly resin which is far cheaper.

If a thicker than ordinary deck layer is selected and the proper foam used a teak overlay can once again be screwed down.

It doesn't look as yachty ,but Treadmaster would be a good selection if the boat is going out to blue water..
Click to expand...

FF ,I am definitely not liking that idea. Have you actually ever done this or seen this done? I can't visualize how you would deal with the existing deck hardware. Build your new deck around it??? If the decks are leaking around the railings or cleats or deck fittings (which they probably are) you're still going to be getting water intrusion getting into the original deck. The water is going to keep on doing damage. Plus, it'll KILL the resale value.
If the boat is a keeper, just fix the dang thing like it's supposed to be fixed.
 
I've injected gorilla glue with success in rot over the years.

It does remove water but not moisture. You drill a hole and a relief hole and inject.. I've had water shoot out of the hole after being displaced(almost 5' in the air once).

I'd say it will work well for areas up to 2'x2' but you'll need to drill alot of holes and in the end may want to just cut the core out of that area with a shallow saw, recore, resin and if you're lucky drop back in the old cutout.

If injectadeck is anything like gorilla glue it's much much better than epoxy for this use.

Keep in mind that once it's used it bonds to just about anything and is rock hard.. if you decide to cut out the deck later on you've made the work more difficult.. You will have to grind it off and the "plug" option is gone.
 
I agree, the website is a bit lacking, no excuse for it. So nobody who has answered has tried it or know of someone who has. I know the right way to fix this, it's just not worth it to me. I know the source of the leaks is the deck screws. So far 80% are gone replaced by a nice solid plug of epoxy that extends somewhere below the top skin. Some places had large voids, and some had little to none. I countersunk the epoxy and installed teak bungs to keep the appearance of the deck. I know the next guy may have a tougher time with repairs, but he'll probably get the boat for nothing in another 10 years. 9,000 hours on the Lehman, original steel tanks, etc.
I am leaning towards continuing my present course of epoxy, but wanted to know if anyone had any experience with this stuff. The amount of expansion and short working time are negatives. Going into blind holes it would be very easy to overfill and get the stuff everywhere. With the epoxy, I may have one hole take 1oz while the adjacent hole takes 8. Also the epoxy has time to soak along voids, refilling a hole several times is not unusual.
Anyway, as stated, no easy way out.
 
"The structural integrity of the boat no longer exists. Wouldn't want to take the boat past Brenton Point on a rough day with outgoing tide."

Not going to happen with my wife on board! [emoji15]
 
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I think it's just a high density urethane, with hydrophilic additives.
mike66 said:
The amount of expansion and short working time are negatives. Going into blind holes it would be very easy to overfill and get the stuff everywhere.
Click to expand...
Yes and solvent (acetone I believe) only works before that very short cure time is up. After that scraping / sanding is the only way to clean up, very nasty stuff, similar to Gorilla glue.
 
"FF ,I am definitely not liking that idea. Have you actually ever done this or seen this done? I can't visualize how you would deal with the existing deck hardware. Build your new deck around it??? If the decks are leaking around the railings or cleats or deck fittings (which they probably are) you're still going to be getting water intrusion getting into the original deck. The water is going to keep on doing damage. Plus, it'll KILL the resale value.
If the boat is a keeper, just fix the dang thing like it's supposed to be fixed."

Yes I have seen it done here at my place in FL.I glassed the deck .

It is fast and although labor intensive only requires one skilled worker , and a grunt helper.
Outside nice weather is a big help. FL winter is dry season.

The concept is to create a structural repair , not just a patch job that may or may not work.

ALL deck hardware is removed , cleats ,windlass, fuel- water fills stanchons and the lay up extends to the hull, in order to have structural strength.

After completion hardware is re installed for a foam cored deck , a different technique than used for a ply deck with glass overlay.

The value will go up not down as the boat now has structural integrity
, however this change will not add enough to the structure of the vessel so it can go offshore, unless it was designed as a voyager and deck rot was the only problem.

It only gets pri$y if the owner "upgrades" to a new windlass , bigger cleats Etc , although Treadmaster IS expensive.

In the past I have described an epoxy / coarse mosquito netlow cost no skid ,probably in the archives.
 
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