beam (width)

Beam, often referred to simply as width, is a fundamental yacht measurement. As noted in Wikipedia’s list of large sailing vessels, beam denotes the width of the hull. It is measured in meters or feet at the design waterline and does not include rub rails, folding keels, or other protruding elements. A wider beam increases initial stability and allows for more spacious interior layouts, which is why modern cruising yachts tend to have generous beams. However, extreme width can increase drag and reduce upwind performance, and it may lead to a quicker, more jerky motion in a seaway. The connection between beam and handling is particularly noticeable on yachts with twin helms — we explore this in detail in our article «Why are there two helms on a yacht?». Designers always consider beam relative to waterline length; a classic racing yacht might have an L/B ratio around 3:1, while a modern cruising catamaran can be significantly wider. In everyday sailing, knowing your beam is essential for negotiating locks, booking marina berths, and calculating sail areas. For a broader look at how beam interacts with other design elements, visit the «yacht design» topic.