20 Portland Road, Kilmarnock

18 Portland Road in Kilmarnock is a pair of semi-detached, 2-storey, 2-bay L-plan houses built around 1855. They feature coursed ashlar, harled and painted surfaces, with a heavy projecting architraved eaves course, a projecting base course, and moulded window margins.

On the north elevation, No 18 has a door on the ground floor to the right, framed by an architraved surround and a scroll-bracketed canopy that ends in a stepped plaque. To the left, there is a single window with an architraved surround and a projecting lintel. The first floor has two regularly placed bays, with a moulded eaves course that projects east beyond the building's line. No 20 mirrors No 18 but has the ground floor window and door positions reversed, with the moulded eaves course projecting west beyond the line of the building.

The east elevation connects to a lower terrace (Nos 10-16). The south (rear) elevation was not seen as of 2001. The west elevation features an architraved door surround leading to the adjoining house and a service passageway at the extreme left of the ground floor. The rest of the elevation is blind, only interrupted at the attic level by a gutter.

No 18 has later 2-pane replacement glazing, while No 20 retains 2-pane timber sash and case windows. The piended grey slate roof has lead ridges and flashings, with a cast-iron 2-pane Carron light positioned near the ridge to the left of center. There is a brick gablehead stack and skews shared with the lower terrace to the east, while the stack and skews on the west gable are missing. Concealed guttering runs along the front elevation and follows the side elevation of the building, with downpipes leading to the rear.

Inside, some original timber features remain, including skirting boards and doors. No 18 is currently used as business premises.