Conservatory, Carisbrooke, 108 West King Street, Helensburgh

This is a villa with a conservatory, built in 1860, and with significant additions made by William Fraser in 1901, located at 108 West King Street, Helensburgh. The building comprises a two-storey and attic, three-bay villa, a single-storey service wing on the west side, and a later two-storey wing and conservatory on the east side. The villa is constructed of red and cream sandstone rubble, with cream snecked and stugged sandstone rubble on the south elevation, and squared and snecked sandstone for the additions. Ashlar dressings are also used throughout.

The south elevation, which is the main entrance, features a gabled porch in the re-entrant angle, with a shouldered-arch doorpiece, fanlit boarded door, and decorative iron hinges. A window is located on the return to the right. Above, there is a window on the first floor. To the left, a tall gabled bay has a slightly advanced tripartite window at ground level, and corniced windows to the first and attic floors. A saw tooth coping sits above the tripartite window, acting as an ashlar apron to the first-floor window. To the right, another gabled bay features a corniced tripartite window at ground level, a window above with a curved apron, and an attic window to the gablehead. A later, advanced two-storey gabled block extends to the outer right, incorporating a projecting window at ground level with a piended red tiled roof, timber mullions arranged 1-5-1 with fixed small panes above. Three stepped and cusped round-headed windows are situated above this, with mock half-timbering to the gablehead apex.

The west elevation has a single-storey gabled wing attached, with a pointed-arch niche to the gablehead. The north elevation shows a single-storey service block in the centre and a door on the return to the right, with a tall stair window above. A later gabled wing extends to the outer left, displaying four narrow windows at ground level with stained glass, and two round-headed windows above with cusped tracery and stained glass. The east elevation has a rectangular conservatory attached which is accessed from the villa via a tripartite French window.

Most windows are four-pane sash and case, with lead-pane glazing to the later wing. A grey slate roof is topped with ashlar stacks, original cans, and a central rooflight flanked by two gabled dormers.

The interior includes a double arcade dividing a hall from a reception room, featuring a timber Art Nouveau chimney piece. The drawing room in the later addition has geometric compartmental plasterwork to its ceiling. A mannered tripartite arcaded screen divides the room, with a modern chimney piece and windows flanking, wainscot, and a barrel-vaulted ceiling. A French window provides access to the conservatory, along with an adjoining tripartite window. A former billiard room on the first floor of the addition has a barrel-vaulted ceiling. Art Nouveau stained glass windows are present within the addition, within four inglenook windows on the north side at ground level and to north and south windows on the first floor.

The conservatory, also designed by William Fraser in 1901, has an ashlar plinth and a timber framework with fixed plate glass panes and fixed small panes above a row of pivot windows. A rectangular lantern features pivot windows and access is provided through a door to the east. The property is approached by ashlar piers and two-leaf timber boarded gates.