DIY spray foam insulation

For those that dont know, closed cell expanding foam works for excellent sound and heat insulation. Its the best to use. even steel boats use it for the builds.
I have used it in my boats and app;lied it to other folks boats in steel and GRP type. You would surprised i guess at how good it is.
It does need to be applied correctly though. easy enough but can be messy.
 
Falcoron said:
If you actually took the time to read the thread instead of popping in to troll you might have got the jist of the post ffs!
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In hindsight, you are right and I must apologize, because all your OP was asking is where to get that foam, and my post was useless in this respect.

So, to be consistent with your wish to avoid trolling, I will refrain from mentioning the reasons why I think (no, wait, I'm actually sure) that in the long run you will regret having done that on your Broom - and even more so in UK climate.
And also why I wholeheartedly disagree with waynes world that it's the best way to insulate a boat interior, regardless of the hull material, hence including steel - albeit I can see why he used that stuff if, as his post suggests, he did it as a job.
Good luck.
 
jrudge said:
If it worked then the manufacturer would install it. If you see it on a house roof you run a mile. Same with a boat. It is more likely to lock in water than remove it. Do as you wish but if you come here and get peoples view then don’t get upset when people disagree with you.
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You see if you do homework, like I did, this is waterproof closed cell, bonds tightly to the substrate and creates a barrier between warm and cold surface so stopping all condensation in the area coated. Along with a Vapor barrier lining it’s as good as it gets for insulation at a very good price.
So yes I did what I wished. Cheers.
Manufactures would use? Feck me the way most boats are made especially older ones like mine with rotting foam linings that harbour damp and mould and untreated wood that’s water logged and rotted, fibreglass full of air pockets and wiring that would scare a ghost hunter, please!
 
waynes world said:
For those that dont know, closed cell expanding foam works for excellent sound and heat insulation. Its the best to use. even steel boats use it for the builds.
I have used it in my boats and app;lied it to other folks boats in steel and GRP type. You would surprised i guess at how good it is.
It does need to be applied correctly though. easy enough but can be messy.
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Absolutely! Some folk just can’t see anyone doing differently. This was easy applied slow expanding, so easy to control, for a DIY product it’s really good.
I sprayed a little box with it and left out during very wet then freezing weather and it’s as dry as can be no water ingress at all.
 
MapisM said:
In hindsight, you are right and I must apologize, because all your OP was asking is where to get that foam, and my post was useless in this respect.

So, to be consistent with your wish to avoid trolling, I will refrain from mentioning the reasons why I think (no, wait, I'm actually sure) that in the long run you will regret having done that on your Broom - and even more so in UK climate.
And also why I wholeheartedly disagree with waynes world that it's the best way to insulate a boat interior, regardless of the hull material, hence including steel - albeit I can see why he used that stuff if, as his post suggests, he did it as a job.
Good luck.
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Can i ask why you disagree and think its so bad to use. good to hear why folk think things are wrong that have been done for many years with no ill affect..

I didnt do it as a job but did it to customers request, not my specialty just part of work i did. Only down side on steel boats is the possibillity of welding needed to be done. If so then its a strip out.

Curious as to why the proffessioanls use it for years and years and never a problem on steel boats so why would there be on GRP.
 
waynes world said:
Can i ask why you disagree and think its so bad to use. good to hear why folk think things are wrong that have been done for many years with no ill affect..

I didnt do it as a job but did it to customers request, not my specialty just part of work i did. Only down side on steel boats is the possibillity of welding needed to be done. If so then its a strip out.

Curious as to why the proffessioanls use it for years and years and never a problem on steel boats so why would there be on GRP.
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It’s the usual, never used it but an expert!
For the past 25 years I worked for a very large engineering company that manufacture and build huge containerised diesel gensets, ( now retired)
In many ways similar to a steel boat with huge diesel lumps heating the structure, as a wet paint SME specialising in corrosion protection covering UK and Northern Europe mostly Scandinavian countries.
So I know a thing or two about condensation on cold surfaces when any form of heat touches it from the inside. One thing I can tell you is most insulation will at some point get wet or damp if there is the slightest gap or the vapour barrier isn’t up to scratch to seal the insulation. All sorts of insulation is used in these units including closed cell foam in certain conditions. Never once was the foam soaked or gave issues. Cannot say the same for the other types used. Any issues were re-engineered using modern alternatives that solved-any problems. Over the 25 years technology moved on and so did the material choices, again old is not always good.
Now! My boat has been stripped down to the glass fibre internally, removing all the crap foam, inferior linings and any wood that has been touched by damp or water from condensation. I can tell you now there was a lot. So Broom are really well put together boats no doubt that but old is not always good! Some of the material and the way it was fitted was crap! Nothing I will replace will be of poor quality and will be really well protected before closing up.
This spray foam I used , which is closed cell fully water proof, was applied carefully with no gaps. Where I could it was applied twice ,
1, use up what I had and 2, to ensure the areas where past condensation was really evident was given the most cover.
Even with well applied closed cell foam a vapour barrier layer is always best policy then taped up air tight with proper aluminium foil tape.
The vapour barrier I used is 9mm thick foil on plastic type which in itself provides the same insulation properties as 25mm rock wool., but unlike that it is waterproof. The only area I wanted done was the ceiling in the sedan area as that is not double skin so was always going to condensate. The wall in the head is mostly below waterline and as it was exposed after strip out I coated that, it is going to help and insulate that area a bit better. It’s never going to be seen again after fit out. I can tell you now there was a lot of condensation in these areas before spraying., especially the ceiling area in sedan.
Weeks after doing, and during very wet and very cold conditions the boat inside is warm and bone dry! Not one area is damp, condensation on windows is 80% less than before and I’m very happy with results.
When new treated ply and wall coverings are fitted the boat interior will be much better that before.
The sound proofing is an added bonus too.
Cheers!
 
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waynes world said:
never a problem on steel boats
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Have you ever seen that on boats built to class, hence subject to periodic inspections?
If so, how did the surveyor check the integrity of hull weldings?
Not that this is irrelevant in other boats, mind - just not mandatory.
 
Falcoron said:
It’s the usual, never used it but an expert!
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Falcoron, I already apologized for my first post on this thread, which made you jump in the conclusion that I am a troll.
Now, I would appreciate if you could stop making assumptions on someone you know absolutely nothing about.
 
Fair enough, apology accepted, but! you couldn't just leave it there you had to add you wee bit in that YOU KNOW! Thats a bit of stealth trolling right there.

But lets leave it there.

My boat my choices.
cheers
 
My understanding is that spray foam (correct spec obviously) is a minimum requirement on steel pleasure craft? Fiberglass not so much due to the materials properties but the theory is sound. Insulation may not have been a consideration on these boats in the 70's when they were used in summer and weather patterns were a little more stable (as much as they can be in Ireland) but times move on. One question I would ask is that Broom's of this vintage were a single laminate or possibly had a wooden core material in places like the foredeck, In more modern boats where foam cores are more common, certainly above the waterline, does this provide better insulative properties? The other question is whether this is required when a high proportion of a boats superstructure is single glazed glass which on a a 70's boat is poorly sealed. Surely thats like leaving the back door open? But if the OP is happy with this approach I cannot see any harm.

PS. OP, I worked for the same company as you ~20years ago as a young lad and I think I recall them foam spraying the inside of the containers.
 
Hi Ferris ( same surname as me! :) )
I only wanted to do the ceiling on the sedan roof as it is a single skin and condensation was really bad, dripping on me when i was working in the boat and yes the single glass windows are an issue, they are what they are, piss poor!
Areas with a core were not an issue so left alone.

The reason i went this route is because the old insulation, ( foam on vinyl head cloth) is rubbish, was damp and very mouldy as the condensation would gather above it and would never be a job. I did start off with closed cell foam sheets but that too was of little use and was hard to seal properly., and water still gathered and dripped down from time to time, so it was removed and i sprayed on the closed cell foam.
The difference in the cabin is astounding, cutting all condensation on the roof section to zero, so making the cabin inherently drier. this has also improved the amount of water on the inside of the glass, not totally but a big improvement and the heat inside the cabin is really nice compared to the bare roof. ( staying in and not colliding with the cold surface of the roof.

yes, some containers that required extra protection in Nordic, Arctic and off shore conditions were foam sprayed, these never gave issues or had to be maintained or insulation replaced. not in my 25 years anyway.

The points you make are very valid, on this occasion i am certainly happy with the choice and the results.

cheers take care.
 
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I am very interested in what you are seeing. Family has a similar vintage broom continental. The original vinyl roof linings are mostly intact and seem to be dry and sound. I have no doubt the backing foam is rotten as you have described but I am minded to leave well enough alone as long as they look decent. What we are doing is refurbing the aft cabin and I am wondering if there would be merit in spraying the hull sides before refitting the paneling.
 
Ferris said:
I am very interested in what you are seeing. Family has a similar vintage broom continental. The original vinyl roof linings are mostly intact and seem to be dry and sound. I have no doubt the backing foam is rotten as you have described but I am minded to leave well enough alone as long as they look decent. What we are doing is refurbing the aft cabin and I am wondering if there would be merit in spraying the hull sides before refitting the paneling.
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A guy I know who is linked to the Scandinavian boating scene said a number of liveaboards there have insulated the hulls on their GRP boats and apparently it's made a huge difference. If the foam is thermally insulating and will be hidden from sight & won't interfere with access to electrical bonding or external fittings/seacocks, then personally if you are in the process of a cabin renovation, now would be the ideal time to add some proper insulation to the hull. I can't speak for current boats but historically GRP boats i've seen have had virtually nil thermal insulation.
 
Cant see any harm to be honest and yes leave well alone if ok, the mess is horrible.
i bought this boat with the inner ripped out of her so a blank canvas.
h so far done a rewire of all the heavy cables, new alternators, new fuel filter system, removed 2 smaller fuel tanks ( 4 on this boat) cleaned out the 2 large port and starboard diesel tanks from years of crap, put in a hot water heating system with 30ltr calorifier fitted radiators ( hate warm air heaters) new battery banks ( starter and leisure 24v system) fitted with victron chargers CRX's etc. etc.
getting started on galley and head with new cooker, fridge, electric quiet flush head to go in new gulper pumps and water and gas lines replaced with new. 80ltr Holding tank fitted too, the list goes on and on.
Now I'm out of the bilge engine room area. ( has twin Hino WO6D 6cyl turbo engines) new bilge pumps fitted too.
That lot has taken a lot of time and money and a toll on my aching knees. 200 mile round trip doesn't help either so only weekends to work on her.
been at this since April 2021 Covid and wife having cancer operation didn't help either :(
( thankfully all good now and all clear)

There was a headlining there but it was sagging and rotten. so ripped out too. So this has been sorted , so onwards and upwards.
I hope to get into water this year sometime. but big ask working alone learning on the way.
 
I started in the boat trade back in 1980, since then i have worked on a lot of boats that had foam of one type or another in.
Usually this involved digging soggy stinking foam out of decks, bilges & sub decks or Rudders to replace rotten timber or glass.
No matter what manufacturers claim about closed cell foam. It all soaks up water. All of it.
Sooner or later its like a dead weight sponge. Poxy stuff!
 
Keith 66 said:
I started in the boat trade back in 1980, since then i have worked on a lot of boats that had foam of one type or another in.
Usually this involved digging soggy stinking foam out of decks, bilges & sub decks or Rudders to replace rotten timber or glass.
No matter what manufacturers claim about closed cell foam. It all soaks up water. All of it.
Sooner or later its like a dead weight sponge. Poxy stuff!
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Problem is Most foam applied is probably open cell and horrible, without knowing what product was applied you wont know how good it is or if it is proper closed cell, a lot of stuff on the market is open cell but touted as closed as it skins over, that in itself is not good. good quality closed cell is water impermeable, but i would not use it where is would be sitting in a bath of water, that is not wat it is for.
I did a small box with this sprayed in and so far weeks later it is still dry with weeks of heavy rain in sunny, ( not) Fermanagh!!
I didn't do anywhere near the bilges. i did a ceiling so well away from any water.

Any foam we sprayed on container walls in my previous job was good quality closed cell and never gave an issue with waterlogging or condensation after being sprayed on correctly left to cure and a vapor barrier fitted correctly too. I'm sure you have seen horrors on boats, Most boats i looked at when buying had a disaster somewhere on or in it by improper maintenance or shoddy DIY work.
i would not apply this on low potential water logged area's or over wood or electrics. I did this to cure an issue well above the water and it has.
My roof wooden struts were treated with epoxy resin before i got near it ( probably at factory) and are in a very solid dry state i applied the foam between these onto the single skin of glass fibre.

But every story and application is different, but I am happy the way i applied it, sealed the area with good vapour barrier and well away from the low parts of the boat. it will be a few months before im ready to fit new ceiling, so will see if any issues appear, so far through very wet wether and freezing conditions i haven't fingers crossed.

I care nothing of the condensation below deck as it gets channelled into the bilge then pumped out.

Cheers
 
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Falcoron said:
Fair enough, apology accepted, but! you couldn't just leave it there you had to add you wee bit in that YOU KNOW! Thats a bit of stealth trolling right there.

But lets leave it there.

My boat my choices.
cheers
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Sounds like a weird attempt to disguise your interest in what I said by calling it now "stealth trolling".
No worries, anyway.
If there's something I fully agree with you, that's both your final suggestion and conclusion.
 
MapisM said:
Sounds like a weird attempt to disguise your interest in what I said by calling it now "stealth trolling".
No worries, anyway.
If there's something I fully agree with you, that's both your final suggestion and conclusion.
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If you want foam that needs to be 100% closed cell than a sprayed PU or PIR is not the route you need to follow. They all have a certain open cell content by design, without that they'd shrink. Also, all PU and PIR foams absorb water into the polymer. Even commercially produced steel faced PU/ PIR panels produced in heated tooling have an open cell content, admittedly lower but they cure due to the external heat source as well as the exotherm of the polymerization, so don't shrink ( if done right !). .....I spent 25+ years in the PU foam industry on the technical side of things.

Extruded PE or PP closed cell foam is about the only cost effective option if you really need it to be closed cell/ water impervious.
 
Not doubting your expertise at all mate!
As stated before this will not be near any water or bilge areas, its inside the sedan on the ceiling. ( about 10' from the water)
What i wanted was to close the thermal bridge between cold and warm.
That will stop condensation forming on the cold skin, so I'm happy with that.
A good quality vapour barrier was also applied and sealed to stop any chance warm air hitting the cold surface.

Happy with my choice and i see no issues whatso ever having seen first hand how it worked for years without issue on containerised gen sets in cold countries and in some off shore applications where the traditional rockwool panels failed and waterlogged with condentsation. This was removed and the area sprayed with closed cell foam.

Not one failed to do its job and there was never any water trapped in the foam over years in service.

I am sure you have seen many disaster's on boats i think we all have from time to time.

cheers
 
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