Marine Survey Guide: What Surveyors Look For (and How to Pass)
Understanding what a marine surveyor checks — the inspection process, common findings, costs, and how to prepare your boat to pass with flying colors.
A marine survey is a thorough inspection of your boat by a certified surveyor. Insurance companies require them every 5 to 10 years. Lenders require them at purchase. Smart buyers request them before any major transaction. Here is what they check and how to prepare.
Types of surveys
Pre-purchase survey: most thorough. Buyer pays. Covers structure, systems, safety, and value estimate.
Insurance survey: confirms hull integrity and current value for underwriting. Required periodically by most insurers.
Damage survey: assesses repair scope and cost after an incident.
What surveyors check
Hull: tap test for delamination, moisture meter readings, blisters, gelcoat cracks, keel and rudder bolt integrity.
Engine: compression test, hours, oil analysis, exhaust system, mounts, alignment.
Electrical: AC and DC systems, grounding, battery condition, panel layout, wire gauge.
Plumbing: through-hulls, seacocks, hoses, holding tank, pumps.
Safety equipment: life jackets, flares, fire extinguishers, navigation lights.
Standing rigging (sailboats): age, condition, swage fittings.
How long it takes
A typical survey on a 35-foot boat takes 4 to 6 hours. Add 2 to 4 hours for a sea trial if included.
Costs
Roughly $20 to $30 per foot of boat length. A 40-foot boat survey runs $800 to $1,200. Plus haul-out fees ($300 to $600) if not already on the hard.
How to prepare
Clean everything. Surveyors see clean boats and assume the rest is also maintained. Dirty boats invite scrutiny.
Have records ready. A binder of maintenance receipts, manuals, and prior surveys signals a serious owner. HullBook users print this in one click.
Open access panels. The surveyor will need to see bilge, engine, electrical panel, and behind storage areas.
Note known issues yourself. Surveyors respect honesty. Hiding a known problem destroys your credibility on every other point.
Common findings
Loose hose clamps. Worn impeller. Outdated flares. Galvanic corrosion on shaft. Soft spots in deck. Battery terminals corroded. Out-of-date safety equipment.
Address these BEFORE the survey. They are cheap to fix and reduce the surveyor's list of negatives.
After the survey
You get a written report. The valuation guides insurance and resale price. The defects list guides repair priorities.
If you are buying: every defect is leverage in negotiation. Use it.
If you are selling: fix what you can, disclose what you cannot, price accordingly.