One authority describes the hull as steel, but that refers to the multi-chine steel or aluminum plan set rather than every completed Offshore 38. The design was clearly intended to let builders choose a material suited to their shops and cruising plans.
Design and Construction
The Offshore 38 was engineered from the outset for several building methods rather than a single factory mold. Its round-bilge fiberglass and cold-moulded wood-epoxy plans sit alongside multi-chine steel and aluminum versions, resulting in an unusually broad range of completed hulls. A documented steel-hulled example confirms that the metal option wasn’t merely theoretical.
With a length-to-beam ratio of 3.37, the hull is moderately narrow for a 38-footer. Its ballast ratio is 43 percent, giving it a meaningful ballast fraction. The displacement-length ratio of 161 puts the design among what one review calls “light racers”—a surprising label for a boat with the construction flexibility of a cruising offshore design.
Rig and Handling
Roberts offered two documented rig options: a masthead sloop and a ketch. Both use the same sheet specifications: 11.6-meter jib and genoa sheets with a diameter of 14 mm, a 28.9-meter mainsheet also measuring 14 mm in diameter, and 25.4-meter spinnaker sheets of the same 14 mm size. These specifications are consistent across both rigs. That commonality suggests the deck plan could accept either rig without re-engineering the winch leads.
The capsize screening value is 1.81, which indicates that, by that formula alone, the boat could be accepted to participate in ocean races. A Motion Comfort Ratio of 26.3 and a sink rate near 1,373 pounds per inch describe a hull that settles predictably under load.
Wetted surface is roughly 441 square feet, while the SA/D ratio is 13.61. Together, those figures describe a moderate underbody with conservative sail area relative to displacement.
Performance Under Power
Documented engine installations include a Yanmar 3QM30 and a Perkins 4.108, both driving through shaft-drive transmissions.
With the Yanmar, cruising speed is 6.0 knots and maximum speed is 7.0 knots. The Perkins installation has a calculated maximum speed of about 7.9 knots, matching the displacement-hull limit for a boat of this length. These figures show that the Offshore 38 is no slug under power, though her speed remains bounded by displacement, as expected of a 38-foot offshore hull.
Accommodations
Headroom aboard the Offshore 38 is above average for the class, a useful quality in a boat intended for extended liveaboard use or ocean passages. That standing room, combined with the cruising-oriented rig options, suggests interior volume better suited to life on passage than to strict racing-weight control. Beyond headroom, however, the interior layout isn’t described.
Verdict
The Bruce Roberts Offshore 38 is a genuinely versatile offshore design. Its principal strength is the range of construction materials available under a single Bruce Roberts design. It rewards a buyer or builder who understands which construction method best suits the intended cruising, while its documented rig and engine choices reflect a boat conceived for real passage work rather than showroom uniformity.
Pros
- Plans offered for fiberglass, wood-epoxy, steel, and aluminum construction; the design is available in multiple construction media
- Masthead sloop or ketch rig options with shared sheet geometry
- Above-average headroom for its size
- Capsize screening value supports ocean-race acceptance by formula alone
Cons
- The displacement-length ratio of 161 earns the label “light racer,” which may mislead cruising buyers
- The SA/D ratio of 13.61 is conservative, implying modest sail power in light air
- The interior layout isn’t described beyond its headroom
