Beauty and the beast: What are the pros and cons of commercial and military conversions?

Many owners envisage building their yacht from scratch – but does transforming former military, research or supply vessels for private use make more sense? Ahead of the 2024 Explorer Yachts Summit, which will take place on 13 November at the Yacht Club de Monaco, Charlotte Hogarth-Jones debates the good, the bad and the ugly of embarking on a refit conversion…

It is often thought that there are two options available for those wanting to own a superyacht: buy one – be it something semi-custom or currently on the brokerage market – or build your own from scratch. There is, however, a third path that’s often overlooked. That’s the route of buying a vessel from another sphere – be it a military training or spy ship, scientific research vessel, tanker or cargo ship – then rebuilding it in the form of your own private, luxury superyacht.

Refit conversions, as they are called, aren’t particularly common. There are some magnificent examples out there, but a lot of projects emerge from the sheds without much fanfare, their owners being keener to test their new toy out in exciting and exotic locations than to generate any media hype.

It’s a world that’s shrouded in mystery, too. It needs a special kind of owner to take the plunge with an unknown vessel, having little certainty around costs, timelines or any surprises along the way. The rest of us know even less than they do about how the journey is about to unfold.

But fortune favours the bold and those who have been there and done that wax lyrical about everything from huge volume cabins and tried-and-true hulls to more sustainable credentials and savings not to be sniffed at. One thing’s for sure; these highly personalised, unique yachts are truly in a class of their own.

Pros

Seaworthiness

Perhaps the most obvious argument for buying a tried-and-tested vessel, especially when considering adventurous travel, is that the hulls have already been put to the test. It’s certainly one that’s hard to argue with.

“She’s extremely strong compared to modern boats,” says Jan Verkerk, owner of 70-metre Sherakhan, a former Dutch training vessel. “Her hull is four centimetres thick, compared with a modern boat with a maximum of 1.8 centimetres.” He owned the 77.4-metre Soviet icebreaker Legend during her conversion, too. Verkerk had grand plans for where Sherakhan would travel – Canada, Greenland, Iceland, Antarctica – “all places where you absolutely need a seaworthy boat,” he notes. 

“When you are making an expedition boat, you need a strong boat, with a strong engine and a strong hull – so it’s the right decision to choose [one] that has proven it can do the job.” After that, “you can make all the luxury you want and it’ll be stronger and better tested than any superyacht on the market.”

Erik Vonk, owner of 46-metre converted trawler Scintilla Maris, followed a similar logic. “Why build something new?” he asks. He had always planned to use either the recycled hull of a conventional tugboat or, preferably, a trawler for his own conversion. “The lines of both of those have evolved from schooners and represent the epitome in what can be achieved in speed, seaworthiness and seakeeping quality,” he notes. “Plus, they’re elegant.”

Superyacht designs, he explains, tend to focus on optimising space and saving weight, and aim for as straightforward a construction as possible. By contrast, “a trawler hull is all about strength, survival and go-anywhere-under-all-circumstances capabilities – regardless of weight and construction challenges.”

That’s the owner’s perspective, but how do those who are manning the yachts feel about them? “A vessel with a long track record definitely inspires confidence and allows us to push the boundaries of what is possible,” says Rob McCallum, co-founder of travel exploration company EYOS, which regularly leads yachts into extreme environments.

Conversion vessels often have longer endurance with more space for fuel, provisions and refuse, he explains, citing the fact that Legend can complete multiple Antarctic charters without having to refuel, while 88-metre icebreaker Arctic P undertook a record-breaking voyage to the Ross Sea. In the case of tug conversions such as 49-metre Asteria, a deeper draught is also an advantage for seakeeping and ice navigation.

John Hughes has been a specialist conversion yacht broker since the late 1980s, and has found and sold boats including 72-metre Nansen Explorer and 59-metre Intuition II. He highlights research vessels as a particularly wise choice. “They’re used to being in rough weather and staying offshore for months at a time,” he notes.

Vonk certainly believes that, in his case, the conversion strategy has paid off. Scintilla Maris is “one of the most solidly built, best-handling sea vessels one could wish for,” he says. “She can go anywhere, any time.”

Time

On paper, starting a project with a yacht should be quicker, right?

“If you’re looking at doing a conversion, it can take six, nine months… people talk about saving costs, but really the saving comes from the time it takes,” says Hughes, who can cite numerous examples of refits that were in and out of the sheds super fast.

As you might expect, how quickly you can turn one around depends on the scale of work required. With a custom yacht, you have the advantage of knowing exactly what needs doing and how long that’ll take. Conversions are that bit more complicated.

“With Jester, more and more things needed to be done,” says Gemma Tuersley, who led on the most recent refit of the impressive 69-metre USSR Ice Class survey vessel conversion at design studio RWD. Originally converted to a private yacht in 1999 (formerly known as Olivia), and with a final conversion in 2011, she recently underwent a two-year renovation, launching in April 2023 in time for the owner’s maiden voyage to Antarctica.

One issue owners struggle with is the ability to accurately retrieve the technical construction data of the donor vessel. “Usually, they have been used for a long time beyond their original scope, and it’s unlikely that you’re able to collect all of the up-to-date data, including any modifications that have been made throughout the vessel’s life,” says Daniela Duck, head of new build division at Camper & Nicholsons. “To a certain extent, you have to discover what lies beneath while you convert the vessel, which doesn’t allow for an accurate cost and time forecast.”

Starting with the right platform vessel can shave valuable months off the build and help to avoid tedious procurement times for new parts, says Micca Ferrero, owner of Icon Yachts. Owners can wait up to 18 months for certain machinery and electrical pieces, which delays the whole build, he says.

It’s hard to gauge an average turnaround time, because there’s a sense that some refit conversion owners relish the production process – for every owner claiming a rapid refit, there are others for whom it’s their life’s work. Scintilla Maris took a staggering 17 years to finish but, says Vonk, “after decades of boat ownership and experience, I wanted a vessel that embodies all the dos and don’ts stored on my hard disc over the years.” 

He’d earmarked a decade to carry out the project, working solo except from some guidance via yacht builder Damen Maaskant. “I have enjoyed each and every minute of it. The extension was, in fact, a pleasure,” he says.

Costs

If there’s one thing sure to catch owners’ attention, it’s the mention of costs. And – good news – the general consensus is that conversions are undoubtedly cheaper.

“I can say that with 100 per cent certainty,” says Hughes. At least 60 per cent cheaper compared with doing a new build, he estimates – or that’s what used to be the case. Throughout the 1990s, having worked on yachts in the South of France, he made an easy living as a conversion yacht specialist. 

“Brokers started calling me and saying, ‘We have a client who wants to convert,’” he recalls. “I’d call ship brokers who’d say, ‘We don’t deal with rubbish like that,’ so I realised there was a gap in the market.” Soon, owners were tracking him down from all over the world and big deals were being made.

“When the ships come on the market, it’s mainly because the owners think they’re past their sell-by date,” he says. “On Nansen Explorer I got a hell of a deal; she was very cheap. We came in with a tongue-in-cheek low offer that was rejected, then at a board meeting it was accepted. I think it was under £1 million.”

Verkerk reckons 60 per cent is ambitious in today’s market, which Hughes admits has changed drastically in more recent years. “You can do it cheaper but not for half the price,” says Verkerk. “If you make 30 or 40 [per cent cheaper], I think you’re a hero.”

A former build captain on a 60-metre conversion puts it clearly. “Doing a conversion is cheaper than a new build, but it is still very expensive, depending on the finishes and amenities selected.”

That, it seems, is often the sticking point. Conversion owners have to make difficult decisions, frequently playing off luxurious changes that make the boat feel more like a superyacht against associated costs. “Do you want it to be fully quiet, always?” asks Verkerk. “Or are you happy with the little ‘brrrrrrrrr’ [noise] on the back? I’m happy with it – and to say I wasn’t happy, the difference is €10 million.”

Joris Saat, project manager and owner’s rep at Damen, says: “Finding the right donor ship makes all the difference. If most of the technical equipment can be saved this will be cost effective. But if an owner wants to convert a commercial vessel into a superyacht with teak decks, glass railings and a high-end interior, it will be impossible.”

Often, yards price in an element of risk and pass on these costs to the owner. “We made some detailed research into a particular project for a client, which found that initial offers from conversion shipyards were indicating a range of costs, as opposed to a turnkey range. That range was always relatively high in order to correctly protect the builder,” remembers Duck. The cost factor was the reason the client eventually eschewed a conversion.

McCallum advises clients on whether donor vessels are, in fact, suitable for converting into expedition superyachts. “We have had several vessels that a buyer was keen on due to the price, but that would have ended up costing as much as a new build,” he says. 

The yachts in question were often ex-military vessels, where the original design parameters were expensive to modify – think small rooms, additional bulkheads, low ceilings, open cable ways, asbestos and so on. Older-style offshore support boats also present challenges around fuel consumption and stability.

In Vonk’s case, the hull of Scintilla Maris was below its replacement value. “So, in that sense there have been savings,” he says. However, in comparison to a new build with a hull built to yacht standards, “there are no savings of any significance at all”.

Philip Naylor, head of marine and technical services at Burgess, gives a reality check. “The conversion and renovation will probably take longer, and cost just as much, as buying a comparable second-hand vessel that is in good condition, or where the work has already been done,” he says. “I am reminded of the quip among owners of vintage Rolls-Royces. ‘What is the difference between a £10,000 Rolls-Royce and a £20,000 Rolls-Royce?’ Answer: about £30,000 of restoration costs.”

Sustainability

One big positive of converting a vessel has to be the sustainability aspect. Using a hull that already exists versus creating a brand new one is undoubtedly more responsible.

“First, the existing hull has been saved from the scrapyard, and second, no new hull was built,” Vonk points out. And, in his case, the original fishing trawler using a 4,400-horsepower diesel engine is now a high-tech hybrid propulsion vessel.

“Refits and conversions are generally always environmentally friendlier than complete new builds,” says Robert van Tol, executive director of Water Revolution Foundation, an organisation that aims to help the yachting community reduce its negative environmental impact. “Of course, there is waste coming from conversions too, but when the hull and superstructure are preserved, that saves significant upstream impacts when looking at the entire life cycle of a yacht.”

Using an existing vessel primarily saves on raw material extraction, transport, manufacturing/processing and transport to a yard for construction, too. Of course there are exceptions, van Tol says, “but consider that the ship would have otherwise gone to scrap – that is again a process with impact.”

Owners should be aware that the build process might involve more experts and partners than a traditional new build – for example, those well versed in what to do with scrap material from the donor vessel. 

At Icon Yachts, which has converted a number of boats including Legend and 68-metre Q (formerly Ragnar) and is currently working on 70-metre “family explorer” Project Master, Ferrero is keen to point out that not all waste material and machinery removed from the donor vessel is necessarily wasted.

“During the conversion of Project Master, great care was taken to ensure that every piece of material removed was evaluated to see if it could be reused in some way,” he says. The two fast daughter crafts have been converted into swish tenders – an open one for expeditions and a closed one as a limousine tender. 

The “old but reliable” Rolls-Royce main engines were dismantled by experts and sold for spare parts. The same applied to the pumps and other smaller machinery, while the original cranes on board the smaller lifeboats were sold to existing standby lifeboats, where they are now installed as essential equipment.

“My favourite example, however, is that the mattresses from Project Master were donated to an NGO who took them to the Ukraine to be used in shelters for displaced people,” he says. “All these individual items may be small, but when you add them up, the effect is significant.”

Space

Lastly, devotees claim that conversion vessels are not only better, but also bigger, with significantly more room on board than new builds of a similar length. Jari Lindgren, current captain on Richard Burton’s former yacht, Kalizma, and a former captain on board multiple 100-metre-plus yachts, can attest to this first-hand. 

“One of the yachts I worked on was converted by a European client; I guess he wanted a conversion as it may have worked out cheaper than building a new one. Originally, she was an operational passenger vessel in class so minimal changes were done, mostly cosmetic changes to her hull and then the guest spaces. Five decks were gutted bare and new staterooms were built in lieu,” he recalls, adding that 26 palatial cabins took the place of 120 old ones.

“The vision was to cater for future VIP charter guests with large entourages,” he says. “The hydrodynamic properties were altered in the hull modification process and she lost over a knot in top speed,” he adds, “but it was as the owner wanted.”

In addition to more space for owners and their guests – and, in the case of expedition craft, for supplies and separate vehicles – another big plus can be better areas for crew.

On Jester, “I’ve never seen such a generous galley,” commented Tuersley. “It was just amazing – the chefs are really happy, the crew is really happy, and it filters down.”

Ferrero confirms that conversions, particularly those of offshore vessels, “usually offer considerably more space than conventional “white yachts”. For comparison, he notes that a 70-metre offshore conversion offers about the same volume equivalent as a 90-metre to 100-metre new-build superyacht (about 3,000GT).

“This is largely due to their greater beam,” he explains, which not only provides more space, but also allows for more unusual layout options. Yet, he cautions, all this room isn’t always a good thing. 

“Owners sometimes fail to grasp how large these yachts become due to the volume – and the resulting financial implications. All these spaces need to be filled and the luxury interior is the main price driver on these yachts. It takes some good education on the part of the yard to get this across, as in the client’s mind they are ‘only’ buying a 70-metre yacht, but in terms of space they are actually buying a much bigger one.”

Cons

Major rebuild

That’s the pros out of the way. Now it’s time for a sharp intake of breath as we discuss the downsides. First and foremost, it cannot be overstated how much of a major rebuild these conversions are, and whether you’re signing up for a refit, a rebuild or essentially a 100 per cent new build that’s being slotted into an old hull, is something owners will want to think very carefully about. Projects do often involve stripping the yacht right back to simply the hull, which might need significant work to get it into a seaworthy condition, too.

“A vessel that has had a former life is going to be an old ship,” says Naylor. “Unlike fine wine, a ship does not improve with age – quite the opposite. An old vessel can be expected to have many hidden problems. Inevitably it will require extensive steelwork, and the pipework, plumbing and electrical system will require wholesale renewal.”

As will the engines, he points out. Almost all will need replacing in order to comply with the latest emission standard IMO Tier III. “The exhaust system for these types of engines occupies a lot of space and ventilation and cooling can be a challenge,” he notes.

On Jester, the engine remained the same, but everything else was “stripped, gutted”, notes Tuersley. “I don’t think that there was anything untouched on the whole boat.”

On board Legend, Verkerk wanted to keep the old engines to maintain the original feel of the ship. “It was challenging,” he admits. For his second yacht, Sherakhan, he took a different, easier path. “The engine was broken, so I didn’t even try to fix it,” he notes. “I simply said, ‘Make the engine room clean and start again.’”  A large portion of Legend also had to be replaced because she’d been damaged by a fire in Russia and had then laid dormant in Genoa for the best part of a decade.

Lindgren makes a good point that not only is it environmentally better to re-engine a yacht, “it is nearly impossible to find spares for old engines”, so it rarely makes sense to maintain them. “I know of a recent conversion that was completely gutted and rebuilt from keel to mast,” he says. “Not sure why they even bothered with an old hull, but go figure.”

Often, that’s the story. Vonk classes Scintilla Maris as a “new build in a recycled hull” and is keen to stress that refits and rebuilds of this ilk shouldn’t be lumped into the same category.

“When the work started, there was no infrastructure; other than the bare hull – as in frames and plating – 100 per cent of everything is new,” he says. Much like the ship of Theseus, it begs the question, is a yacht still the same yacht, if all of it has been replaced over time?

Lindgren recalls a similar project he worked on for a Middle Eastern client. “I suspect here the onus was on privacy and someone managed to sell the concept of an old hull as an idea for conversion, as one was readily available. Very little remained of her hull once she was rebuilt, just the tanktop and then some, [while] the rest of her outline was built several times over. The project took a very long time – eight to nine years – so I am not sure how economically viable it was in the end, if at all, all things considered.”

How much of the donor vessel you can and want to maintain  is a key question. By stripping out a lot of the interior, Vonk emphasises you can “avoid a number of the ‘an old ship is an old ship’ issues”, and bypass a number of significant headaches. The pay-off, however, is that any savings come from keeping as much of the original vessel as possible. Get rid of that and your costs soon become comparable with a new build.

Clever modifications are key to making the yacht feel more like a classic superyacht. “I’ve seen some yacht and ship conversions that didn’t meet expectations,” says designer Timur Bozca, who worked on the 146-metre Japanese semi-submersible transport vessel OK. “Common issues often include inadequate structural modifications, which can lead to stability or safety problems. 

For instance, converting a cargo ship into a luxury yacht without reinforcing the hull or properly redistributing weight can result in performance and handling issues.” His sentiments are echoed by Hughes: “What  I always say to these guys doing conversions is: don’t forget to put stabilisers on them. Because these things are designed to roll.”

If there’s one thing that is for sure, it’s that there’s never been a better time to do some rigorous homework. “Owners and their team should have a finalised general arrangement and required specs in place to present to various shipyards to bid on,” says the build captain. 

“Once a shipyard is selected, a complete build spec should be developed, GA finalised and budget agreed on – before beginning any work.”

Design challenges

Are you on good terms with your designer? If not, it might be time to get a little more friendly. Conversion projects throw up a whole host of unusual design questions, and not all of them can be easily solved. 

With a new build, of course, you’re starting from a blank sheet of paper, whereas conversion vessels often have certain parameters in place that are immovable. “A drastic change of the geometry of the donor vessel is highly unlikely,” says Duck, “since it would go against the logic of trying to recover part of the existing vessel.”

“There are some small differences,” explains van Clerk, “you can take a menu of things you can hide, but yeah, they’re always going to be there – it will never be the same as a born superyacht.”  On Jester, design teams had to navigate restricted ceiling heights, camber throughout, even a crew area full of concrete.

Sometimes, too much space can present a challenge. “Everything with those ships is forward, including the engines. So what are you going to do with all that space?” asks Hughes.

Bozca came up with plenty of ingenious solutions for OK. “[The vessel] presented unique challenges, but its semi-submersible nature also supported our floating island concept,” he says. “With 100 metres of the yacht capable of diving underwater, we aimed  to create an unparalleled maritime experience.” 

A significant challenge was “maintaining the yacht’s powerful base while making minor design changes to achieve a sleek look”, as well as incorporating large windows and skylights to allow some natural light in, without compromising structural integrity.

“There’s an onboard botanic garden providing a lush retreat at sea, a multi-functional sports court for tennis or basketball, and a spectacular pool surrounded by aquariums housing exotic marine life like sharks and moray eels,” he says. 

“Additionally, a 100-metre open deck garage accommodates various vehicles, from trucks to seaplanes. The yacht also features a master cabin with a 360-degree view, offering unparalleled vistas and luxury, while a glass elevator with a full view enhances the experience, allowing guests to enjoy the stunning surroundings as they move between decks.”

Scintilla Maris has an unusual feature, too. Instead of the usual beach club at the stern of the vessel, her outdoor living area is amidships, surrounded by water-level boarding zones to port and starboard. “The central location, with proximity of the water on both sides, provides an entirely different user experience than an extended deck at the rear of the boat,” says Vonk. “Creating new features like this, drawing on many years of experience and breaking away from conventions, is what gets my adrenaline flowing.”

Reclassification

Almost all conversion vessels require some kind of reclassification as part of the process. Certainly, it’s something to consider before buying your donor vessel, or indeed, building. Classes include passenger ships, small passenger ships, big passenger ships and, of course, superyacht class.

“Sherakhan was already a passenger ship in her old life, so I didn’t need to change her status, which made it a bit easier to do the conversion,” says Verkerk, but adds that classifications “always give you a very big headache, for sure. The newest stability and leaking stability request from the class associations are pretty heavy and not applicable for these kinds of boats.”

There are sometimes hybrid situations. Having worked on two huge conversions, Lindgren recalls: “Both vessels are, as far as I know, now part of a private fleet for a Middle Eastern client. They most likely operate like passenger vessels, with the relevant rules and regulations in place, but are on a private registry as private vessels. Like yachts, but on a massive scale.”

Hughes always advises owners to reclassify. Often the classifications have expired and, in any event, “the price gets lost in the conversion cost circle,” he says.

Saat says Damen is actively lobbying most classification societies “to discuss better solutions for reclassification and help them understand how to keep it simple and give a ship a second life”.

Ferrero gives a good guide for novices. “The basic rule of thumb is quite simple. If the vessel’s parameters (length, beam); propulsion (such as installation of different engines); or classification type (from offshore rescue vessel to yacht) are changed, the conversion is regarded as a major conversion, which means that the vessel in its entirety must comply with the latest rules and regulations,”  he says. “There may be certain exemptions that class may allow, but in general one should not count on them.

“This means that if I am adding a five-metre extension as part of the conversion, I need to make sure that, for example, my existing and perhaps 20-year-old engines comply with the latest exhaust and emissions regulations. There are also often major implications on the electrical side. For example, it used to be common practice, especially on commercial vessels, to paint over the cables running in the technical spaces. This is no longer allowed, so if one of the three factors for a major rebuild is triggered, it can mean that almost the entire electrical installation has to be rebuilt. None of this should frighten anyone, as there are ways of avoiding such pitfalls, but these issues need to be considered at a very early stage.”

Looks

Ah, the elephant in the room. Conversion yachts are often the ones crowds stand and point at from the docks – and not always for the right reasons. 

“M/Y Yas was converted from an old Dutch corvette – I’ve seen comments of her as the world’s ugliest yacht somewhere,” recalls Lindgren. Surely not what the owners had in mind. “I still think she looks pretty futuristic. The biggest differences come from between the old and new part of the conversion,” he says, “and how they manage to meld them together.”

He believes the worst offenders come from the cruise-ship segment, where “old vessels have been complemented by more cabins and visible sponsons to comply with new legislation, and they can’t flaunt the grandfather rule any more. “These conversions or add-ons are sometimes merely ill-shaped boxes welded on to the hull,” he continues, citing M/S Stockholm as a case in point.

When I ask John Hughes how you’d recognise a conversion vessel from afar, it prompts a wry chuckle. “You just want to look at them,” he says, “you know exactly what they are.”

Still willing to take the plunge? Your next step is to find a specialist conversion vessel dealer and line up a team of specialist advisers who’ll make a solid panel of experts. You need “someone who can really read the stability books, understand the construction of the boat, and then you need to go for something with a tremendously good maintenance period, because the key to everything in shipping and yachting is maintenance”, advises Verkerk. Government, military and high-end shipping company vessels tend to be good in this regard, he says.

“It’s crucial to match the yacht’s design characteristics with its intended use to ensure optimal performance and satisfaction,” advises Bozca. “Yachts designed primarily for high-speed performance might not be the best choice for long-term cruising, due to their limited fuel capacity and reduced comfort. Conversely, larger luxury yachts with extensive amenities might struggle in rough seas or shallow waters due to their size and draught.”

Those used to perusing the docks of Monaco and Cannes might need to steel themselves before going ship hunting. Hughes recalls the appalled faces on some guests that he once arranged a last-minute viewing for, as they approached the boat. “The broker turned to the customer and his wife and said, “Oh my god! This is filthy!” Of course it was,” he laughs. “The thing had been at sea for six months!”

“All old boats, they stink,” agrees Verkerk. “And they’re dirty. There’s nothing happy on an old boat.”

Speak to the owners and they’ll say that while their vessel has turned out to be the craft of their dreams, it’s been a hell of a lot  of work. “It takes a lot out of you – 14 hours of work a day,” says Verkerk, wondering out loud if he’ll ever have the strength to do another. And yet, there must be something profoundly rewarding in having been through the whole process. Almost every owner  I speak to already has their eye on another project too.

“I’ll never do one again… OK, I have an idea, but it will be much smaller, it’ll be a 50-metre,” says Verkerk.

“Would I do it again? Yes,” enthuses Vonk. “I already know one or two hulls to go after… But that is a secret.”

First published in the November 2024 issue of BOAT International. Get this magazine sent straight to your door, or subscribe and never miss an issue.