Sail area / displacement
How much sail the boat carries for its weight — its power in light air.
- not published: sail area
How it is worked out
sail area (ft²) ÷ (displacement as ft³ of seawater)^⅔
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ALIN2811_1-1-scaled — Sirius-Werft
Summary
- Length overall
- 34.8 ft
- Beam
- 11.6 ft
- Draft
- 2.8–6.9 ft
- Displacement
- 17,857 lb
- Berths
- 2–6
* A standard reference image, not the actual boat — shown to help visualise this model's published dimensions.
Sailing Ratios
Classic yacht-design ratios worked out from the builder's published figures, each shown against the bands designers read it by.
Displacement / length
How heavy the boat is for its waterline length. Lower is lighter and quicker; higher is steadier and roomier.
- 247· Moderate
How it is worked out
displacement (long tons) ÷ (0.01 × waterline length in ft)³
Ballast ratio
The share of the weight carried in the keel — a rough guide to stiffness, though how deep that weight sits matters as much.
- not published: ballast
How it is worked out
ballast ÷ displacement × 100
Comfort ratio
Ted Brewer's measure of how gently a boat moves in a seaway. Higher means a slower, easier motion.
- 32.1· Moderate offshore
How it is worked out
displacement (lb) ÷ (0.65 × (0.7 × LWL + 0.3 × LOA) × beam^1.333), lengths in ft
Capsize screening
A guide from the inquiry after the 1979 Fastnet race: below 2 was taken as suited to ocean passages. It ignores hull shape and where the ballast sits.
- 1.77· Below 2
How it is worked out
beam (ft) ÷ (displacement as ft³ of seawater)^⅓
Hull speed
Roughly the speed a displacement hull reaches before it has to climb its own bow wave.
- 7.6 kn
How it is worked out
1.34 × √(waterline length in ft), in knots
Most builders publish a light displacement. The ratios were defined on a loaded boat, so every boat here reads a little lighter than a surveyor's figure would — all alike, which keeps them comparable.
Tanks
What the builder publishes about how fast, how strong and how much the boat carries.
Fuel and water on one scale: a tank twice the height holds twice as much.
- Fuel40 galWater58 gal
10 gal of water per berth
Design Category
Certified CE design category A (Ocean): the wind and waves the EU Recreational Craft Directive says this boat is designed to take.
- D
Sheltered waters
- Wind
- up to Beaufort 4
- Waves
- up to 0.3 m
- C
Inshore
- Wind
- up to Beaufort 6
- Waves
- up to 2 m
- B
Offshore
- Wind
- up to Beaufort 8
- Waves
- up to 4 m
- AThis boat
Ocean
- Wind
- above Beaufort 8
- Waves
- above 4 m
Design limits set by the EU Recreational Craft Directive (2013/53/EU), in significant wave height. A category covers the conditions of those below it. It is the limit the boat was designed to, not a promise that it is safe in any conditions within it — that judgement stays with the skipper.
Dimensions
- LOA
- 34.8 ft (10.6 m)
- Hull length
- —
- LWL
- 31.8 ft (9.7 m)
- Beam
- 11.6 ft (3.53 m)
- Draft (min)
- 2.8 ft (0.85 m)
- Draft (max)
- 6.9 ft (2.1 m)
- Air draft
- —
- Displacement
- 17,857 lb (8,100 kg)
- Ballast
- —
- Cabins
- —
- Heads
- 1
- Berths
- 2–6
Sail Plan
- Main sail
- —
- Jib
- —
- Genoa
- —
- Sail area
- —
- Downwind sail area
- —
- Rig type
- —
Engine and Tanks
- Engine
- 51 hp (Volvo Penta)
- Engine count
- 1
- Engine manufacturer
- Volvo Penta
- Propulsion type
- saildrive
- Fuel capacity
- 40 gal (150 L)
- Fresh water capacity
- 58 gal (220 L)
- Black water capacity
- 36 gal (138 L)
Construction
- Mast material
- —
- Hull material
- hand-laid GRP, vacuum-bonded sandwich above the waterline, vinyl ester gelcoat
- Deck material
- —
- Keel type
- —
- Rudder type
- —
- Steering wheels
- —
Builder's Own Figures
- Beam at waterline
- 3.15 m
- Keels
- Single fin: 1.98m (Standard) 1.90m / 1.60m (Optional) Twin keel (optional): 1.55 / 1.30m Swing keel (optional): 0.85 – 2.10m
- Interior
- custom-built for each owner; build time four to six months
- Ballast
- 2.6 t
- Engine
- Volvo Penta diesel D2 50, 37.5 kW (51 HP), saildrive
- Layouts
- 2-, 4- and 6-berth versions, custom interior
- Tanks
- standard tanks; larger tanks optional (the page prints 'from … upwards')
- Displacement basis
- as printed, no load stated
- Draught basis
- range over the keel options printed (swing keel raised to the deepest option)
Figures read fromsirius-yachts.com/yachts/35ds· Technical dataread 10/18/2026
Layouts & Drawings
4 drawings from the builder's page: general arrangement, sail plan, profile.
35_for2_standard — Sirius-Werft
35_for4_fixed-keel — Sirius-Werft
35_for6_standard — Sirius-Werft
35_for4_swing-keel — Sirius-Werft
About Sirius Yachts
Semi-custom
Family-owned yard in Plön, northern Germany, building hand-made deck-saloon cruising sailboats since 1971 — the Sirius 35 DS and 40 DS, each with a custom interior and a choice of fin, twin or lifting keel.
Sirius Yachts describes itself as boats 'built by craftsmen, with love, since 1971', from the family-owned boat builder that invented the phrase 'deck-saloon'. From its German yard it offers a range of go-anywhere deck-saloon sailboats with hand-crafted, custom-built interiors in mahogany, each available with a single fin keel, a lifting keel or twin keels, and no two yachts from the factory are identical. The yard says it brings nearly half a century of experience building deck-saloon yachts and the experience of more than 650 owners to each new boat: it works through hundreds of design decisions with the buyer — from the rig and sailcloth to the reading lights in the master cabin, and galley drawers made to fit the owner's own cookware — before production begins. The build then takes four to six months; most owners visit the yard several times, receive regular progress pictures by email, and can leave their cutlery, crockery and glassware with the yard so that its storage is made to measure.
Visit brand pageThe Sirius Yachts Range
Every model Sirius Yachts publishes, by length — where this one sits in the range.
- Sirius 40 DS42.3 ft
- Sirius 35 DS· this model34.8 ft