Cathedine Fawr farmhouse including attached kitchen and granary range

Cathedine Fawr is a characteristic gentry farmhouse dating from around 1700. The building has a T-shaped plan with a central entrance, single-depth main rooms, and a shallow staircase. The service cross wing is the same height as the main roof, and there is a single-storey outshut at the rear left. The farmhouse is constructed of painted stone and features a hipped Welsh slate roof with stacks that have cornices; the right end has an external stepped stack, with another stack at the rear wing.

The symmetrical two-storey frontage includes a central pedimented bay with a small attic window, a large cross window on the first floor with a cornice above and a crest and datestone below. The central front doorway is unadorned and has stone steps leading to a replaced door. On the first floor, there are additional cross windows under the eaves on each side, and two similar windows on each side of the ground floor. A continuous hoodmould extends across the entire frontage.

To the left, a separate two-storey block is connected to the main house by a short passage. This block has a steep pitched Welsh slate roof with an end stack adjacent to the main house. On the opposite side, there are steps leading to the first-floor granary, which features a door with a hood under a shallow dripstone, along with two small-pane windows that have shallow dripstones and a stone ledge below facing the lake. There are also further attached extensions.

Inside, there is a wide central hallway with a high ceiling and a fine open well wooden staircase with turned balusters in the staircase bay at the rear. The stairs ascend from the cellar to the attic through five flights. The rooms on each side are single depth, although a service room is incorporated into the staircase bay. The kitchen bay has chamfered and stopped beams on the ground floor.