Roberts 36s are generally built in steel or aluminium, most commonly in steel. With a long keel, cutaway forefoot, several rig choices, and layouts intended for extended living aboard, the design has proved adaptable enough for substantial owner refits and serious offshore passages.
Design and Construction
The Roberts 36 measures 36 feet 9 inches overall and 28 feet 9 inches on the waterline, with an 11-foot beam. It is a hard-chine design most often built in steel, though aluminium is also an option. Manufacturer records specify a multi-chine hull in steel or aluminium; the pilothouse variant may instead use fiberglass.
The hull has a long keel with a cutaway forefoot that aids maneuvering in tight waters, a configuration described in the original as part of the boat’s steel-and-aluminium construction profile. Its length-to-beam ratio is 3.34, while the immersion rate is about 251 kg/cm. The result is a predictable, heavy-volume hull rather than a featherweight racer.
Displacement varies by construction material. The fiberglass or wood versions displace about 14,750 lb, while the steel boat is listed at 18,000 lb. Fixed ballast is 6,275 lb. Draft also depends on ballast: 4 feet 0 inches with lead and 4 feet 9 inches with scrap steel. Separate references put loaded draft near 5 feet 5 inches and at 1.45–1.55 m depending on load, so the sources differ.
Build quality naturally varies among individual boats. One surveyed steel pilothouse example, Zen, was described by its surveyor as one of the best-built steel boats he had seen anywhere. Its interior was finished with professionalism and attention to detail.
Rig, Handling, and Performance
The Roberts 36 is normally cutter or ketch rigged. The manufacturer identifies cutter or ketch as the standard arrangement, with a junk rig also possible.
The long keel and cutaway forefoot give the boat a predictable character. One owner’s extended 37-foot conversion, Alcazar, was reported to have a comfortingly solid but not heavy helm. It was also very predictable under sail and while berthing.
Under way, Alcazar held a steady 7 knots, with brief surges to 8.5. It motored at 6 knots using a marinised 40 hp Perkins above a Volvo saildrive. Another owner’s boat, Ppalu, recorded a best day’s run of 166 nautical miles and completed two transatlantic passages, along with Mediterranean and Caribbean cruises.
The capsize screening value is 1.79, and the sail-area/displacement ratio is 15.16. Those figures are consistent with a modestly powered offshore cruiser.
Accommodations
Full headroom is provided in all layout versions, and the boat has enough volume for serious living aboard. References list six berths in two cabins as standard, though one owner reported seven berths and another conversion could sleep seven to nine.
The Alcazar refit achieved 6 foot 6 inch bunks throughout after the ceiling height was raised for men over six feet. Its heads were moved athwart the engine near the main hatch.
A junk-rigged boat formerly named Minerva 3 even carried a bath—a feature its owner claimed no other yacht possessed. The pilothouse Zen was surveyed as having a very well laid-out interior, a great deck, and a comfortable cockpit. Together, these examples show how readily the basic plan accommodates different deck, coachroof, and interior arrangements.
Known Issues
The documented defects are limited. On the steel pilothouse Zen, the surveyor’s main recommendation concerned a very slippery deck. This is the only recorded structural or safety caveat in the sourced record, and no other widespread fault is attested.
Draft and displacement vary with ballast and construction material, which can complicate comparisons between individual boats. Sources also give conflicting berth counts.
Refits and Ownership
Owners have treated the Roberts 36 as a blank canvas. Will Blackie’s Alcazar received a gentle hull extension to 37 feet, a safe center cockpit, a roomy stern cabin, and a practical stern deck. Its boom was extended to carry a full cockpit tent. A Cornish three-point block-and-tackle mainsheet replaced the traveler to simplify the arrangement for family use.
Emily Wiltshire’s Tarasana, formerly Minerva 3, has been owned for nearly 20 years on the Queensland coast. Sailor Aleixo Belov built a Roberts 36A in the 1970s–80s and circled the globe three times aboard her. These accounts show a design that rewards long-term, hands-on custodianship.
The Verdict
The Roberts 36 is a proven, adaptable offshore hull. Its hard-chine steel or aluminium construction and long-keel pedigree suit owners who value passage-making over polish. Multiple rig choices, full headroom, and the capacity for radical refits make it a perennial candidate for a serious cruiser prepared to invest time and steel.
Pros
- Proven world cruiser, with more than 300 reportedly afloat and a history of circumnavigation
- Hard-chine steel or aluminium construction, with a pilothouse variant available
- Full headroom in all versions, with flexible berth and cabin arrangements
- Predictable helm and practical reported speeds of 6–7 knots under sail or power
Cons
- A slippery deck was noted in at least one steel pilothouse survey
- Draft and displacement vary by ballast and construction, complicating comparisons
- Berth counts conflict across sources
