Glued in IGU on Vessels Marketed For Offshore Use

Thoughts on glued in IGUS? Even legacy yards like Hallberg-Rassy are now doing it...

 

Welcome to the Forums.
IGU?
Inertial Guidance Unit
Internal Grid Unit
Insulated Glazing Unit
International Gas Union
International Geographical Union
Indian Golf Union
Foz do Iguaçu International Airport

Lots of people from lots of places approaching maritime work from lots of different directions. So often it helps to spell it out.
FWIW, isn't glassing it in just another form of glueing. You would need to undertake a structural analysis to determine the necessary joint requirements. Too stiff can be as bad as too flexible.

 

Are you asking about the pipe chase on the photo?

 

I’m referring to the Internal Grid Unit (IGU) — sorry for not being specific earlier. Let me give some context.

I wasn’t sure how active this forum was when I first posted, but here’s my background: I’ve been sailing bluewater for over 20 years, since I was a child. What I didn’t know much about until recently was hull construction — at least not until I found myself in a bit of a pickle…

I bought a brand-new 34-foot yacht from a very reputable Swedish yard. My plan has always been to circumnavigate, something I’ve dreamed of since I was a kid.

So you can imagine my surprise when, after a minor grounding at about 3 knots leaving Turks & Caicos, the IGU had almost completely disbonded from the hull.

I started making calls — Bob Perry, surveyors, and dozens of other owners with similar hull numbers (post-2019 builds). The consensus was clear: grids that rely solely on a chemical bond to the hull are much more vulnerable than grids that are fully laminated in.

The photos told the story — poor cuts, sharp angles, and shortcuts you wouldn’t expect from a yard with this reputation. And as the IGU was cut out, we found huge gaps in the bonding, with little more than putty holding it all together.

In the end, I pulled the interior and had the entire stringer grid fully laminated to the hull. The difference is night and day. The boat now feels solid, stiff, and actually performs better. That “soft” flex underfoot is gone.

I understand why most owners wouldn’t post something like this — nobody wants to tank their resale value. But for me, integrity and safety come first. A vessel marketed for ocean crossings should be able to withstand the occasional low-speed harbor grounding. That’s a basic expectation in my opinion.

If there is enough interest, I'll post the full survey for you all here. Let me know if you're interested.

 

Glue only would not be what I would consider good building practice, and some may consider me a novice builder. I call myself semi-pro with limited experience.

The problem with bonding only to a narrow area of fixed strength is stress risors. I’d be surprised if your hull hadn’t already experienced bond failures underway if you found voids in the putty.

The strength of the bonding putty must also be questioned, but back to a void, and why they are so terrible. Let’s assume the hull is flexing at the void since the area around it cannot. This is similar to hydraulic failure of a cored laminate where a small area has a void and water pressure moves the void repeatedly until propagation occurs. Same with a void on the grid. Water/wave/slamming would move or flex the hull and propagate more bond failure; especially when the bad hull spot was not supported with laminate or tabbing. Eventually, especially forward areas, would end up with large areas of bond failure. Then your impact was really just the coup de grais.

There are certainly times when a builder must decide whether bonding is sufficient and whether stress risors are super important. For example, a sole. A frp sole does not necessarily require careful management of stress risor, and can be glued down with epoxy fairly well. But it isn’t subject to hydraulics. Just foot traffic. When I bonded the top of the bow extensions on my boat, the engineer actually considered stress risor even and used a pre-release method to decrease the likelihood of delam. Credits to @rxcomposite . He is not posting a lot, but I can imagine he may have a comment on igu bonding if they use it.

The other thing to consider is not all the IGU is subject to the same stresses. Bonding it in with putty assumed so…unless the igu width would vary.

I’m surprised the industry has not addressed it. But perhaps it has fallen to the quick and dirty idea the glue is enough. Another issue is all bonding agents require surface prep. It is really hard to get epoxy to bond to super finely polished surfaces. So, if bonding is done poorly on no key; it, too, can fail.

The manufacturer should have paid for the repairs for bluewater boat.

 

When I picked up the vessel from the yard, I was surprised at the amount of settling I could hear and visibly see. The hull was way underbuilt from day one for a boat marketed and sold as a bluewater cruiser. I was hearing creaking at anchor, squeaking floorboards, and could see bubbling and blistering on the exterior of the gelcoat. Even the Sika was still tacky from the factory months later. These were my earliest warning signs, long before grounding. The synthetic decking they used? Bubbled immediately first season.

Your point about stress risers and voids is exactly what I experienced in practice. The grid wasn’t tabbed to the hull at all — just glued in with putty. That narrow chemical bond created inevitable stress risers. Once voids appeared in the putty, hydraulic pumping with every wave cycle propagated the failure. Surveyors warned me this would eventually lead to large-scale bond loss, especially forward, and that my ~3-kn grounding was simply the coup de grâce that exposed the weakness.

Bonding alone, without laminate tie-in, is not what I or any prudent buyer would consider good building practice for a CE Category A yacht. It may work for soles or furniture, but not for a structural grid that carries keel and rig loads offshore. The EU harmonized standard ISO 12215-9 requires grounding survivability at ≥ 6 kn. My vessel failed structurally at ~3 kn — half that threshold — with progressive delamination visible even before.

The yard did offer to “take the vessel back for repair” — but only if I could deliver her north to the dealer. By the time they acknowledged the seriousness of the issues, I was already 2,000 miles south. I ended up paying for and overseeing the structural rebuild myself. The work was done properly; the boat is perfect now.

I'm just at a loss to know what to think. I am a full time live aboard. Being out here is my life but this is just not the boat to take around the world. Not even close to what it takes. in my opinion.

I need to know, am I crazy? Or are these yards just pushing vessels out so fast they don't care? Most people aren't blue water cruising anymore, so I believe they are building to a lesser spec.

 

I suspect you are worried about litigation, but sometimes the only way to stop nonsense is to name the company and get the matter addressed in professional literature.

I did google the issue, just looking for a professional article or bulletin and saw this problem annotated back in 2008. So the issue appears to be present, at least in production boats, for some time, and your experience not unique.

As a ‘novice’ builder, I’d never trust not tabbing in the floors or stringers, so why they opt to blow one day of work in production environments is pure nonsense to me and worthy of publishing the full story.

I suspect the manufacturers have allowed themselves to be oversold on the incredible bonding agents.

 

I am fearful litigation. The yard has already sent "notice." There attitude is everything was fine when I left the yard. I had many of the same "finish" work issues on umami that the same family had in 2008. The veneer on the european oak is razor thin and of poor assembly and match. same head issues. stanchions pulling out not chain platted. I actually gave that 2008 report to the team in Tortola who worked on my vessel and went over every issue in that case on my vessel to make sure she would be made 100 percent safe. I think some issues were simply new boat problems, shame on me. Other's though, simply not acceptable. Am I crazy?

 

Also speaking poorly or criticizing a legacy yard is in poor taste and i don't want to come across as that. My goal is to figure out how they screwed up so badly, what do to with my vessel now, stay with it or sell it, and what to do next. I'm a young guy, this is going to sink me either way. I work remotely and am full time sailing. I now have to return home. I by no means think it's a "bad" boat like the mia maria case which was absolutely delamination but it's not the boat you would put your family across the pacific in. I emailed Frers, and sent him a full report. He told me "the yard is very reliable," and I responded with a complete copy of the 2008 case. I know I should have bought a contessa 32 but I wanted the interior space to work and since this is my home, I thought I'd get something new just the way I wanted. Big MISTAKE. Just tell me I'm crazy so I can move on with my life. This experience has been absolutely devastating and dealing with this yard is like continuously pricking your skin. Once they label you persona non-grata, they stop communicating. So I can't get any build information from them, they won't give it, no laminate schedules, nothing.

 

Professional literature... Everyone wants to hear until I drop the yards name. I spoke with Bob and he told me I wasn't crazy that these issues were serious and some frivolous and he has helped considerably. Anyone who knows the guy knows he's a zero ******** guy. Since having over 70k of work done on Umami during her first year, I believe she's a great COASTAL cruiser. But not an offshore boat. The broker said whatever he could to get the sale. That's fine.. The only schmuk here is me.

 

I am owning FULL responsibility for this, this is not a wine or a cry. This is "hey this is what's going on and I'm cautiously approaching advice." Please understand that other new owners have spent considerably more than me on their vessels and that associating with me is seen as "sabotaging" their resale value. In fairness though, 5 other vessels same model have had issues post 2019 out of 87 that at the time were built. Furthermore if you look at their latest model that just came out and is only slightly larger, the entire grid structure has been strengthened with massive stainless plates.

 

For a structural hull failure, there is no reason they deserve a pass.

Here is where you get into trouble, though.

Once something is wrong, all you see is the wrong. Go house shopping sometime. Walk in and see wrong things on the way and all the way through you see the other errors.

Now, you start declaring everything wrong and the company gets on its heels in a fight. You are bitching about veneer thickness and a major hull failure.

The issue for you is choosing which things are bad enough to fight about. If you complain about veneer thickness; did you not see a boat of same type before buying? This is how you become persona non grata..

And if the boat was sold as a bluewater boat, that is a claim you needed to verify somewhat.

 

Fair point, and I appreciate the straight talk. You’re right — I don’t want to blur the line between “finish issues” and a structural failure. The veneer thickness, bubbling deck, etc. are annoyances I can live with. The IGU bond failure is a completely different category — that’s the piece that matters, and why I started this thread.

I was impressed by the sailing characteristics, but I didn’t have the knowledge then to evaluate grid construction. My expectation (maybe naïve) was that a CE Cat A boat, marketed for circumnavigation, by such a yard would have a structural grid that could handle more than a 3-kn bump.

So that leaves me here: what now? Do I sell her as a coastal cruiser and move on? Do I go back to the old-school route — find a proven older hull, gut her, and rebuild so I know exactly what I’m sailing on, and if so what hull? That’s why I’m looking hard at what comes next, because this was always meant to be more than a coastal boat for me.

 

If you’ve tabbed the grid to the forward sections of the hull and you feel good about other structural matters like chainplates and the mast, etc. Then sue the manufacturer for your costs and keep the boat and go sailing. They cannot stand on ‘we would fix it’. Substandard work is substandard work.

As a US citizen, a Swedish boat builder has no reach. Get a lawyer and know the law and use it to your benefit. If you get a check, someday when you travel by Corpus Christie, Texas, take me and my wife out for a sail. If they decide not to reimburse you, name them and shame them. It usually ruins their business. Sometimes they will sell it as an improvement, but is very hard to recover from..

You are incorrect about naivety. A Class A boat needs to be built well.

I will tell you the reason I built was I hoped it would be a better built boat, but I ran into design problems and also built the bdeck a bit too heavy. Custom built should generally be better if you control qa.

 

Of course we’ll take you and your wife sailing if you ever come through Corpus Christi. That would be a pleasure.

I’ve already spoken with a dozen lawyers on this, and the first thing they all bring up is the 2008 case. That family ultimately got a new hull, but they also lost over $300k in legal fees—and they never even took delivery of that replacement boat. It was sold off to someone else.

That’s the cautionary tale I keep in mind while weighing next steps. I'm considering selling and refitting a Taswell, older Hylas, or an Outbound. I would love an older Hinckley Sou'wester or even consider refitting an older Hutting.