Ty Oldfield was built as the Llandaff College of Home Economics in 1954, and was purchased by BBC Wales in 1987 to form ancillary administration and other offices to Broadcasting House which sits on the opposite side of Llantristant Road.

In the preliminary structural inspection carried out early in 1987 the site was described as consisting of a main complex of original buildings, linked by suspended bridge corridors to later-built teaching blocks, gymnasium and main assembly hall. Multi-storey dormitory blocks and a two storey teaching flat were located to the east of the main complex, while to the west was a two storey lodge (a late 19th century remnant of the Rookwood House estate) and house.

Blocks 1, 2, 3 and 4 on the attached plans form the original complex, and are of vary heights up to three storeys with semi-basement. They are formed around a single story are which formed the kitchen/stores. The construction of these was of a concrete beam and column framing and brick external skin. Floors and roofs of precast concrete slabwork.

Block 5 formed the main Assembly hall. A high, single story hall with a semi-basement under the north end. Construction again of concrete framing with brick cladding to the walls and concrete floor.

Block 6 was a two two storey block with brick external walls and lightweight partition walls to the interior, timber floor to the first floor.

Block 7 was a two storey block. The external rendered brickwork has infill panel of precast coarse aggregate facing on the north and south elevations. The floor and roof were of concrete slabs, with a central concrete staircase serving all floors on the west side of the building and a concrete spiral staircase on the south elevation.

Block 8 was a largely two-storey block, with a semi-basement on the north side of the building. Externally the walls are rendered brickwork, with ground to roof concrete columns between the windows on the east and west elevations. The floors and roof of concrete, with the ground floor cantilevered on the north elevation. A central staircase served the ground and first floor on the east side of the building, with a concrete spiral staircase on the west elevation.

Block 9 with the gymnasium, a single storey structure with a two storey inter-connecting building which joined it to Block 8. The gynmasium was of external brickwork with timber panelling and glazing to the front elevation. Roof of timber laminated portal construction with a light-weight decking.

Blocks 10, 11 and 12 were three-storey buildings with external brickwork walls and internal concrete column and beam framing. The floors and roofs of concrete construction. A concrete staircase at the west and east side of the building serving all floors. Blocks 10 and 11 were inter-joining.

Block 13 was a two-storey building with external brickwork walls and floors and roofs of domestic design.

Block 14 was a two-storey Victorian lodge house dating to the Rookwood House estate and is seperately listed under NPRN

Block 15 was two-storey domestic buildings with brickwork external walls and timber constructed roof and first. This building was demolished by 2017.