South Lodge, Mount Stuart House, Bute

South Lodge Outbuilding at Mount Stuart House dates from the earlier to mid 19th century. It is a single-storey, three-bay L-plan cottage designed in the Tudor-Gothic style, featuring a gabled bay that projects to the outer left. The building is constructed of coursed grey sandstone rubble with polished sandstone margins, and includes a raised base course, tooled quoins, and tooled long and short surrounds to the openings, which are predominantly bipartite. The design also features architraved hoodmoulds, stone mullions, and projecting cills. The sides and rear are finished with harl-pointed random rubble, and there is a single-storey rubble outbuilding to the northwest with red rubble sandstone dressings.

On the southeast (entrance) elevation, there is a boarded timber door at the center with a plate-glass fanlight above it. To the outer right is a bipartite window, and to the outer left in the advanced bay is another bipartite window. An armorial panel is centered in the apex above the entrance. The southwest (side) elevation has a bipartite window in the outer left bay, a single window at the center, and a blind bay to the outer right. The windows are fitted with 4-pane lying-pane timber sash and case glazing. The roof is covered with graded grey slate and features raised stone skews, corniced ridge and apex stacks, and various circular cans.

The interior was not seen in 1996. The outbuilding to the north is a piended single-storey structure with a single bay and a grey slate roof.

The boundary wall surrounding the site is made of harl-pointed random rubble with round-arched rubble coping. It is flanked by painted obelisk-style piers at the entrance, which are accompanied by cast-iron gates.