20 Carriden Brae, Muirhouses, Bo'Ness

20 Carriden Brae in Muirhouses, Bo'Ness, is a pair of single-storey and attic cottages built in 1864, designed in an L-plan style known as cottage orné. The cottages are primarily constructed from squared and snecked tooled sandstone and feature overhanging eaves and droved chamfered openings.

On the west elevation, which is the principal elevation, the left side has a gabled porch in the low wing, marked with a datestone from 1864, while the right side consists of four bays. The north elevation showcases a four-bay gabled low wing to the right, which is attached to the end gable, both made of rubble. To the left, there is a low three-bay rubble wing that has two doors.

The south elevation of Carriden Cottage features a half-hipped two-bay end gable on the left (No 20) and two recessed bays on the right, with an additional low recessed rubble wing that has an entrance door. The west elevation has modern windows and a replacement door, while the south elevation also has modern windows and a door. The north elevation retains some original leaded lattice glazing. The roof is covered with graded grey slates, and there is a partial stack on the north side, a stack on the east side, and a ridge stack situated between No 20 and Carriden Cottage.

Inside No 20, the layout has been partly altered, with what may have been the original washhouse now converted into a modern bathroom. The original plan, which included four small rooms or box beds at the front of the cottage, is still somewhat visible. Carriden Cottage has been modernised, with further renovations completed in 2003.

The property includes ancillary structures and boundary walls, featuring coping stones from a previous boundary wall to the west, which connects to a short section of rubble wall with a plain square gate pier. Additionally, there is a pig sty in the garden of No 20, which is a rubble-built enclosure with semi-circular coping.