Number 2 Ship Shop (Building Number 1/208)

Number 2 Ship Shop (Building Number 1/208), also known as the West Factory, is a steam engineering works now used as workshops, located on the west side of Boiler Road at HM Naval Base Portsmouth. Built between 1846 and 1849 by Captain Henry James RE, it is a substantial two-storey industrial building constructed in red brick laid in Flemish bond, with granite and Portland stone dressings and brighter red brick gauged flat arches. The roof is of corrugated iron supported on wrought-iron trusses.

The east elevation, facing the Steam Basin, extends across 25 bays arranged in five sections. These sections are divided by projecting single bays with rusticated long and short quoins. Giant round arches with fluted keystones frame the windows, with impost bands that continue within the arches. Pediments crown bays 3, 13 and 23. The recessed bays between these projections are set in pairs beneath giant pilasters and contain giant round brick arches with keystones framing windows. The building sits on an ashlar plinth with an eaves cornice and blocking course. Windows are small-paned cast-iron three-light examples—tall and round-arched on the ground floor, smaller and near semi-circular on the first floor—all with deep stone sills. At ground-floor impost level, a rail for a dockyard crane is supported on massive iron wall plates. The first floor retains a small hand crane and platform at bay 8, a platform at bay 3, and crane housings at bay 23. Rainwater downpipes set against the projecting bays are headed with dates of 1847 and initials 'VR' with a fouled anchor. A roof skylight is present. The rear elevation is similar but without pediments and with most windows renewed; the ashlar eaves cornice and blocking course are restricted to the projecting bays and giant pilasters. The central lower part is concealed by a low brick addition and part of the right side by the Smithery. The north return features giant corner pilasters framing a full-height round archway with rusticated quoins and a cornice below a pediment, with some renewed brickwork evident. The south return is similar but includes a steel roller door to the ground floor and twentieth-century replacement metal windows above.

The interior contains a remarkable cast-iron structural frame of cast-iron beams with parabolic bottom flanges and matching bridging beams, notably long examples that fit into sockets and support brick jack arches. The upper floor employs iron beams with parabolic bottom flanges and cast sockets with timber joists. A gantry crane is carried on a brick corbel band at window impost level and across the windows on metal girders with decorative arched braces. A cast-iron spiral staircase rises to the first floor. The roof is boarded and braced with iron trusses.

The building originally housed the West Factory, which contained (from south to north) the engine erecting shop, the heavy turning shop, the central punching and shearing shop, and two northern sections for boiler construction and repair. The first floor accommodated the millwrights' shop, light turning and fitting shop, pattern makers' shop and pattern store. Shaft drive was taken from an 80-horsepower beam engine positioned at the centre of the rear elevation. The structural frame represents a mature design using cast-iron proportionate to anticipated loads, both live and dead.

Captain James's original intention was for the building to be sited east of the Steam Basin, but this plan was abandoned because the land was not ready. He felt the final building was compromised by its narrow site. The planning of this Portsmouth steam engineering facility contrasts with the more integrated Quadrangle at Devonport. The building is of considerable historic interest as one of the first of the new generation of heavy engineering shops built at Portsmouth and Devonport to support the transition to a steam-powered fleet, and stands in relation to the associated brass and iron foundries.