13, 15 Dundas Street, Bonnyrigg

13 and 15 Dundas Street in Bonnyrigg are a pair of plain classical houses built in the earlier to mid-19th century, with later additions. They are two stories high and symmetrical, featuring five bays. The principal elevation is constructed from stugged ashlar sandstone, while the rear is made of snecked sandstone and sandstone rubble on the northwest side. There is also a brick and harled square-plan addition at the rear. The windows have droved, raised margins, and there are base and eaves courses.

On the northeast (principal) elevation, there is a painted tripartite doorpiece, which is a later addition, located in the inner right bay. This doorpiece has a cornice and blocking course above it, and it features a timber panelled door with a two-light fanlight, flanked by side windows. Above this door, there is a window on the first floor. The centre and outer right bays each have a window on both floors. In the inner left bay, there is an architraved, painted doorpiece with a timber panelled door and a two-light fanlight, along with a window above on the first floor. The outer left bay also has a window on each floor.

The southwest (rear) elevation shows that number 13 has a square-plan addition at ground level in the centre bay, with a window above on the first floor. There are windows in both the left and right bays on each floor. The rear of number 15 is not fully visible.

The windows on the northeast elevation are 12- and 2-pane timber sash and case, while the southwest elevation features 4- and 2-pane timber sash and case windows, along with skylights. The houses have a grey slate roof, with a piended slate roof on the addition. The skews are ashlar coped, and there are ashlar coped wallhead stacks on the northwest and southeast sides. The rainwater goods are made of cast iron.

The boundary walls are rendered ashlar with a ridged ashlar coping.