Apple House adjoining to south of square garden, Plas Newydd

Apple House is a rectangular two-storey storehouse located adjacent to the south of the square garden at Plas Newydd. It is constructed of rubble masonry and features a half-hipped slate roof. The west front has three semi-circular brick arches at the center, each with boarded doors, and to the right, there is a smaller square-headed door that is now partly blocked to create a window. The first floor has five windows on both sides, which are 4-pane casements topped with shallow cambered brick arch heads.

The left end of the building, which has a half-gable, is attached to the wall of the square garden. This end is brick-faced and includes a square-headed doorway that leads into the garden, along with a round-headed window that features Gothic glazing bars in the half-gable. The right end, also half-gabled, has a ramp leading to a central door to the loft, which has a flat stone-arch head. This door is flanked by small windows with brick arch heads that are now blocked. Above the door is a small opening, likely an owl-hole. Additionally, to the left of the door on the ground floor, there is a blocked door with a flat stone-arch head.

Inside, the main part has a tiled floor, and there is a boarded door leading to a separate storeroom on the right.