Marine Surveys

Insurance Guide · Surveys & Pre-Purchase

A marine survey is an inspection of a vessel conducted by a qualified, independent surveyor for the purpose of establishing condition and value. Insurers require them because they need to know what they are insuring; buyers commission them because they need to know what they are buying. The survey report is the document that bridges the gap between a seller's description and objective condition, and it is the foundation on which insurance coverage decisions are made.

Understanding what surveyors actually look at — and what the resulting report means for your coverage and purchase decision — is more useful than simply knowing that a survey is required.

When Insurers Require a Survey

Most marine insurers trigger a survey requirement at one of two thresholds: vessel age (typically 10 years old or older) or insured value (typically above $50,000, though some carriers set this lower). At purchase, virtually all marine insurers will require a survey regardless of age or value, because they are insuring a vessel they have not previously seen.

For ongoing coverage, the standard interval is every five years. Some insurers require a new survey if a covered claim exceeds a certain percentage of the vessel's insured value, on the basis that major repairs alter the vessel's condition. If you are switching insurers with an existing vessel, expect to provide either a current survey or submit to a new one as a condition of the quote.

What a Full Survey Inspects

Hull and Deck

The hull inspection is the core of any survey. The surveyor will examine the exterior and interior of the hull for structural problems, delamination, osmotic blistering, impact damage, repair history, and keel attachment integrity. For fiberglass vessels, a moisture meter is used throughout the hull to measure moisture content; readings above certain thresholds indicate osmosis or water intrusion that can compromise structural integrity over time. The deck is checked for soft spots (delamination under the skin) by walking it systematically and tapping with a mallet.

Osmotic blistering — the formation of blisters in fiberglass hull laminate caused by water penetration — is a specific focus. Minor blistering is common in older fiberglass hulls and is often manageable; extensive blistering affecting structural laminate is a significant finding that affects insurability and value. The surveyor will note blistering by severity and location; the repair cost assessment is for you or your yard to determine, but the surveyor's notes give you the information you need.

Keel and Rudder

Keel attachment is one of the highest-consequence structural elements on a sailboat. The surveyor will inspect the keel bolts from inside the bilge, looking for corrosion, movement, and evidence of stress cracking. External keel condition — particularly for lead keels, which can develop hairline cracks along the hull-keel joint — is examined visually and with moisture meter. Rudder attachment, bearing play, and any evidence of rudder damage are noted.

Systems: Electrical, Mechanical, and Through-Hull

The electrical system inspection covers AC and DC wiring, battery condition, connections, and compliance with ABYC standards. Stray current and galvanic corrosion signs are noted. The mechanical inspection covers the engine, transmission, and driveline — shaft, cutlass bearing, propeller, and stuffing box or shaft seal. Fuel systems (tanks, lines, vented fill caps, anti-siphon protection) are examined for compliance with fire and safety standards.

Through-hull fittings and sea cocks receive careful attention. Every fitting below the waterline is an opening through which water enters if the fitting fails. Surveyors test all through-hulls for ease of operation and examine the adjacent area for corrosion, proper backing plates, and correct installation. Failed sea cocks that cannot be closed are a safety finding, not a minor note.

Safety Equipment

Surveys for insurance purposes will note the condition and presence of required safety equipment: EPIRB registration and battery date, life raft service date and certification, flares within expiration, fire extinguishers serviced and charged, bilge pump operation, and navigation light condition. These are the items most likely to generate an underwriter's requirements list — a set of conditions you must satisfy before coverage is bound.

NAMS vs. SAMS: Which Certification Matters

NAMS (National Association of Marine Surveyors) and SAMS (Society of Accredited Marine Surveyors) are the two main professional organizations that certify marine surveyors in North America. Both require examination, documented experience, continuing education, and adherence to a professional code. Most major marine insurers accept surveys from surveyors certified by either organization; a small number specify one over the other, but this is uncommon.

The more important distinction is type: a hull and machinery surveyor is the credential you need for insurance and purchase purposes. Cargo surveyors, damage surveyors, and tonnage surveyors are specialists in different aspects of marine work. When hiring a surveyor, confirm they hold a hull and machinery certification from NAMS or SAMS and have recent experience with vessels of the type and size you are buying.

Reading the Survey Report

Survey reports vary in format but typically include: a description of the vessel and the survey conditions, the surveyor's opinion of fair market value (important for agreed value policies), a condition and value conclusion, and a list of findings organized by severity. Findings are usually categorized as immediate safety concerns (must be corrected before the vessel is used), required for insurability (the insurer will require correction), and recommended items (advisable but not required for coverage).

The insurer does not necessarily receive the full survey report. Many insurers request only the summary page, the value opinion, and the required items list. However, you should read the complete report — a surveyor's notes in the body of the report often contain more useful information about the vessel's condition than the summary captures.

How Survey Findings Affect Coverage and Premium

A survey with significant findings does not automatically mean you cannot insure the vessel — it means the insurer will set conditions. Common conditions include: proof of repair for specific deficiencies before coverage binds, a reduced coverage amount if the insured value exceeds the surveyor's valuation opinion, or an exclusion for specific systems with known problems (for example, an older electrical system with noted ABYC non-compliance may carry an electrical fire exclusion until it is rewired).

Surveys that reveal major structural problems — keel attachment failures, extensive delamination, severe osmosis — may result in the insurer declining to cover the vessel entirely until repairs are completed and documented. This is uncommon but real, and it is the scenario that makes a pre-purchase survey non-negotiable: far better to discover this before the purchase closes than after it does.

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Frequently Asked Questions

When do marine insurers require a survey and how often must it be updated? Most marine insurers trigger a survey requirement at two thresholds: vessel age (typically 10 years old or older) or insured value (typically above $50,000). At purchase, virtually all marine insurers require a survey regardless of age or value. For ongoing coverage, the standard interval is every five years. Some insurers require a new survey if a covered claim exceeds a certain percentage of the vessel's insured value. When switching insurers with an existing vessel, expect to provide either a current survey or submit to a new one as a condition of the quote.

What does a full marine survey actually inspect? A full survey covers the hull using moisture meter readings for osmotic blistering and delamination, keel bolt integrity from inside the bilge, rudder attachment and bearing play, all electrical systems for ABYC compliance and galvanic corrosion, through-hull fittings and seacock operability, fuel system compliance, and safety equipment status including EPIRB battery date, life raft service certification, flare expiration, and fire extinguisher service dates. A full survey requires the vessel out of the water — a haul-out is not optional. Sea trials are recommended and sometimes required for purchase surveys.

What is the difference between NAMS and SAMS certified surveyors? NAMS (National Association of Marine Surveyors) and SAMS (Society of Accredited Marine Surveyors) are the two main professional organizations certifying marine surveyors in North America. Both require examination, documented experience, continuing education, and professional code adherence. Most major marine insurers accept surveys from either organization. The more important distinction is type: a hull and machinery surveyor is the credential needed for insurance and purchase purposes. Confirm the surveyor holds hull and machinery certification from NAMS or SAMS and has recent experience with vessels of the specific type and size being surveyed.

How do survey findings affect insurance coverage and premium? A survey with significant findings does not automatically prevent insurance — it means the insurer will set conditions. Common conditions include proof of repair before coverage binds, a reduced coverage amount if insured value exceeds the surveyor's valuation, or an exclusion for specific systems with known problems. An older electrical system with noted ABYC non-compliance may carry an electrical fire exclusion until rewired. Major structural problems — keel attachment failures, extensive delamination, severe osmosis — may result in the insurer declining coverage entirely until repairs are documented. This makes a pre-purchase survey non-negotiable.

What is the typical cost of a marine survey and what does it include? Marine surveys typically cost $20-25 per foot for most recreational vessels, placing a full survey for a 50-foot boat at $1,500-3,000. This covers the out-of-water inspection, moisture meter readings throughout the hull, systems inspections, and a written report including a fair market value opinion important for agreed-value insurance policies. The haul-out cost is separate and paid to the yard. The complete report contains more detailed condition notes than the summary the insurer typically receives, and the buyer should read the complete document, not just the summary page.