Do You Need a Marine Surveyor?

Some years ago, I would have always advised anyone buying a boat to have it surveyed by a professional certified marine surveyor.  That is no longer the case based on my own experience as both an owner of many boats and a yacht-repair-yard manager. Basically, we hire surveyors to confirm that a vessel is structurally sound and mechanically in good working order as portrayed by the seller.  We expect them to uncover and report any defects that could affect our decision to buy, or end in an adjustment to the price of the vessel.  And in fact, if you are financing the vessel, the finance company may require a survey.  This does not guarantee you a boat free of defects, however, and there are a few exceptions where you might consider NOT hiring a surveyor.

A marine surveyor inspecting a vessel on land has a limited ability to test all systems

A marine surveyor inspecting a vessel on land has a limited ability to test all systems.

Uncover is the operative word here because the defects to mechanical systems and structural integrity are often unseen. Obviously, surveyors will start with visual clues that lead them to believe there might be more problems than meet the eye: rust stains, leaks, broken ribs or fiberglass damage etc…  Let’s say that visually there are no telltale problems.  The surveyor will move on to actually try the mechanical systems, run the engine etc…  Obviously for a boat out of the water, the surveyor will note in the report that these could not all be tested.  That is why you should always insist on a sea-trial, with the surveyor present, when buying a boat.  The prospective buyer typically pays any expenses related to sea-trialing a boat.

If you are going to buy a boat on dry land without a sea trial, I wonder if you really need a surveyor.  A surveyor would only state the obvious in the report, since the engine or systems can’t be tested, and you can visually judge for yourself if there are any evident hull imperfections. So, If you insist on buying a boat on the beach where the engine(s) haven’t been run, you are running a risk.  A report from a certified mechanic attesting to the condition of the engines, including compression test results, or an explicit warranty from a boat dealer may suffice in lieu of a surveyor’s report.

Structural deficiency may be even harder to detect.  Damage from grounding or collision are the main concerns—and these can be covered up or imperfectly repaired. With fiberglass boats built with core material, water intrusion, particularly in climates that freeze, can cause delamination and the weakening of the hull structure.  Surveyors will use moisture meters and “tap” the hull of fiberglass boats looking for water intrusion or structural voids. These are skills that border on art form and you should query any potential surveyor as to their experience with this type of vessel.  Depending on what kind of material your prospective boat was built with — wood, metal, or fiberglass — I would find a surveyor experienced in that particular construction material or not bother.

In general, I think the relatively small cost of a survey is warranted.  Surveyors don’t guarantee your boat is perfect; rather, they try to give you a realistic assessment of the vessel as is, so read the surveyor’s report carefully and ask questions.  However, if you are not going to give the surveyor the opportunity to check all the systems or they don’t have direct experience with a given type of boat, you may be better off saving the money and foregoing the survey.  Better yet, find the right pro and let them do their job, but be mindful that you’re not getting a guarantee. Boat yards deal with a lot of surveyors and can most likely recommend the appropriate pro for your type of vessel.



  1. Tyrone Mullins says:


    I want to buy a used boat so bad, but, I don’t want to travel thousands of mile, to not only pull/transport the boat, but hire a surveyor, etc. I would like to see it also.

    I personally want to go to the factory directly, buy the hull only, with a few add ons, etc. If the seller wants to throw in a warranty,then, it may change my mind.

    By the way, are there any boat builders out there?

  2. says:

    Looking for the price of a new 2011 Back Cove Hardtop 37ft. List price is OK, however, given the economic climate what should I actually pay for this boat? I love the setup and it would accomodate all my family needs. I’m looking for a fairly good deal! Thanks for any input you might provde.

  3. John Burnham says:

    This note came to the Waterblogged editors from Michael Myers, Back Cove dealer in the Boston area:

    Dear Mr. Sanborn, I was reading through the blog and ran across your post and wanted to offer a quick comment. Unlike many builders Back Cove Yachts has carefully managed dealer inventories and very few stock hulls are available in their dealer network. Unlike some of the high volume builders where there is too much stock and need to offer large incentives to sell through inventory. The dealers are competitive but with supply being limited you can expect low single digit discounts at best. I hope this answers your question, feel free to contact me if you have any additional questions. I hope you do buy a Back Cove 37 as it is an excellent choice. Regards, Michael Myers President Boston Yacht Sales

  4. John Weller says:

    I have an acquantance who will sell me there 30ft boat in Michigan for $10k. Sounds great but it has been drydocked for 14 years. I have not seen it yet, but will do so as soon as the snow is gone. I presume I should focus on any leaks around deck hardware that may have penetrated the fiberglass and in between the deck and hull. If there is core damage, then I would probably avoid the project boat. Any other advise is welcome.

    • John Burnham says:

      John, I think you’re on the right track. I’d be concerned about water penetration from above or below. Some is probably inevitable and can often be dealt with or lived with for a while, but if the boat has a cored construction I’d check it out pretty carefully. Besides the integrity of the hull-deck joint, look closely at the various systems the boat has for steering, electrical, plumbing. You didn’t say how simple or complex this boat is. If there’s a lot to it beyond a hull and deck, hiring a marine surveyor might be money well spent. Talk to your insurance agent, too; you might need a survey to get your insurance, should you buy the boat anyway.

  5. John Densler says:

    It is important to understand the limitations of the tests run by a marine surveyor. In a survey done for me last June, the surveyor claimed that the warning lights that come on when the key is turned on, test if the engine is overheating when running. Really, it rests only that the bulb works, not that the temperature sensor on the engine works. After buying a catamaran with 130 Honda engines (2000 year) I found that running the engines at a dock at 1500 rpm, using a infra red thermal sensor one engine was runnning 20 degrees hotter than the other engine. Using a pressure tester (combination vacuum and gas pressure gauge) one engine was running appreciable less cooling water pressure than the other engine. Note that a sea test is only a partial test of engine performance. It is a necessary, but not sufficiently comprehensive test of performance.

    He did not even pick up that the engines were the ones that had the tendency for block cracking and were no longer covered by the 10 year Honda warranty. There is a great deal more in this case that indicate a less than comprehensive analysis of engine condition. My cost was that of a complete engine repower. Surveyor’s comments, the engines ran to manufacturer’s specifications during the sea test!!!

    In addition, the hydraulic engine lifts leaked oil. After several raising and lowering of the engines, the lifting mechanism ran out of oil and no longer worked. The surveyor’s comment: They worked during the sea test.

    My suggestion, when purchasing a boat with outboards out of warranty with replacement costs over $5,000 get an independent technician certified by the outboard company.

  6. Stan Daniels says:

    I agree with all of the above advice and completely agree that you need both a hull survey and a mechanical engine survey. The surveyors that do each of these have different skill sets. It is definitely worth the cost of both. On small purchases I just check the engine oil and the compression but on anything a bit more valuable I hire a mechanical surveyor to check the engine. Also, some surveyors are now including history reports from to supplement their reports. This is nice for both parties because if there were any negative events in the vessel’s past the surveyor can be on the lookout for remnant damage. The survey looks at the current condition of the vessel the history report looks at items that occurred in the vessels past that could be fine or could still be issues. Good luck and get your boat surveyed :)

    Stan Daniels