Types of marine survey

The descriptions below are by necessity brief and are intended to illustrate the primary differences between the different marine surveys typically undertaken.

Pre-Purchase Survey

The purchase of a new or pre-owned yacht, narrowboat, motorboat or barge is a major expense regardless of the size of the vessel or the intended budget. A pre-purchase survey is therefore highly recommended before committing to any purchase in order to determine that the vessel is as stated in the particulars and to report on the condition of the vessel. Any defects or deficiencies identified are graded in the survey report to help the potential buyer either negotiate a reduction in price or that works be carried out to correct such faults. Pre-purchase surveys are equally applicable to new vessels and should be considered part of the commissioning of any vessel.

Hull Thickness Survey

A hull thickness survey of a steel vessel seeks to assess the hull plating and internal structure to determine the material condition of the hull and any remedial works needed to restore full serviceability to a vessel. Testing is in 3 parts; visual examination, percussion testing and ultrasonic thickness measuring. On completion of the survey, results are annotated onto a hull thickness plot to enable better understanding of any areas of concern and any remedial works required.

Insurance Survey

Many insurers will require periodic surveys of steel vessel to ensure that sufficient residual thickness remains within the steel of the hull’s plating and internal structure. What is often not stated in the requirements of the insurer are those safety critical systems and features on any vessel such as fire detection, fire fighting, bilge pumping, LPG storage and anchoring arrangements. These are all commented on and recommendations made to enhance the safety, and therefore insurability, of the vessel.

Valuation Survey

The value of any vessel is influenced by a combination of the original value, age, current condition, time of year and location. A valuation survey is conducted so as to ascertain the condition of a particular vessel and its valuation relative to similar vessels currently in the marketplace or having recently been sold. By its nature it can be conducted as a standalone activity but is always more informative when paired with a partial or full condition survey.

Sea and River Trials

Sea trials are intended to confirm the satisfactory operation of a vessel’s systems whilst afloat after a period or re-fit or repair. They are conducted in such manner as to test all essential systems and to confirm that the vessel is seaworthy. Sailing vessel sea trials will include hoisting and setting of all sails assuming favourable conditions. Powerboat sea trials will include a full engine system test culminating in a full speed run of up to 30 minutes where conditions allow. River trials for motor and narrow boats are normally limited in their scope due to speed restrictions on inland waterways. Sea and river trials are highly recommended for any vessel prior to undertaking extended cruising.

Rigging Survey

The standing and running rigging of a sailing vessel has to withstand high stresses in use, continuous environmental attack from the elements and should ideally fail in a predictable manner. A rigging survey involves a thorough visual examination of the entire rig, ideally whilst the vessel is afloat with the mast stepped. Specialist examination techniques may include the use of dye penetrant to detect fine cracks.

Engine Survey

The powerplant of any vessel is critical to its seaworthiness and in the case of a motorboat can represent a significant percentage of the purchase cost. It is therefore highly desirable to know as much as possible about the condition of the engine before committing to a purchase. Engine surveys are conducted to give a more thorough understanding of the condition of an engine than would be arrived at during a standard pre-purchase survey. The survey will include a detailed examination of the engine within its operating environment to ensure adequate arrangements exist for cooling, ventilation, air intake and exhaust. The engine mountings and propshaft connections will be examined for serviceability and electrical and earthing connections will be tested. Engine oil analysis can be undertaken both on site by the surveyor and off-site to ascertain the level of contaminants present within the oil, which may offer extra insights into the internal wear pattern of the engine. Further sample tests of the engine coolant may reveal any oil contamination or emulsification.

Damage Assessment Survey

Following any form of collision, grounding, flooding or fire it is essential that a damage assessment survey be carried out prior to undertaking any repairs. Many insurance companies will insist on such a survey to enable a Loss Adjuster to decide any insurance payout. The owner is well advised to seek the assistance of a professional surveyor to represent his interests and to ensure that the full extent of the damage is uncovered and to suggest likely repair options.