6 Sion Terrace, Sion Mills, Co Tyrone, BT82 9HB

6 Sion Terrace is an attached mid-terrace two-bay two-storey house built in 1898, positioned second from the left within a terrace of seven dwellings on the east side of Church Square in Sion Mills. The house was constructed as workers' accommodation by Herdman & Co., the flax-spinning mill company that established and operated Sion Mills as a model village for their employees.

The building is rectangular on plan with a one-and-a-half-storey gabled return to the rear, abutted further by a single-storey flat-roofed extension and a single-storey lean-to extension to the rear; a single-storey canted bay projects to the east. The roof is pitched natural slate with blue and black clay ridge tiles set over a corbelled eaves course. Yellow brick corbelled chimneys serve the party walls and return. Single and double rooflights are original features on the east and west roof pitches respectively. The walls are painted roughcast over a painted plinth, while the return and canted bay are finished in smooth render.

Windows are square-headed timber-framed 1/1 sliding sashes set in smooth reveals with painted masonry sills. The principal elevation faces east and contains, at right, a square-headed opening with a replacement four-panelled timber entrance door with glazed top panels and transom light; the ground floor left is abutted by the canted bay; two windows are located at first floor. The south gable is abutted by an adjoining property. The west elevation is abutted at left by the gabled return; the exposed section at right contains a single 6/6 sliding sash window at first floor, and at ground floor is abutted by the lean-to containing a replacement timber door. The south elevation of the gable contains a single window at each floor; the west and north elevations are blank. The north gable is abutted by an adjoining property. The house is directly accessed from the street at east. A roughcast boundary wall with concrete coping encloses the rear yard, with access through a square-headed vertically-sheeted timber door. A garden lies across a path to the rear, bounded by hedging. Cast-iron half-round gutters and round downpipes complete the external services.

The interior layouts of these simply detailed dwellings have remained largely intact despite modernisation in recent years. Many original features survive, including the yellow brick chimneys, though doors and windows have been replaced, resulting in some loss of architectural unity within the terrace group.

Sion Mills was established by the Herdman family as a company-owned model village from the 1830s onwards, following principles similar to Robert Owen's social experiment at New Lanark. The village was originally built with simple one-storey terraced cottages to house workers and avoid lengthy commutes. At the beginning of the twentieth century, under Captain Ricardo's direction of personnel and welfare, second storeys were added to many houses to accommodate increased workers as the linen trade boomed from 1903 onwards, enabling householders to take in lodgers during the week. The terrace appears on the third edition Ordnance Survey map of 1905; Valuation Revisions records show No. 4 valued from 1880, No. 5 from 1897, and Nos. 6 and 7 from 1898, with Nos. 1–3 appearing somewhat earlier. The houses were described in valuation records as "house, offices and small garden" and were leased from J&E Herdman, with valuations ranging from £6 10s to £15.

Until the 1960s, the Mill employed workers to maintain and repair all village houses, the surrounding grounds, the Mill, its machinery, and the waterpower system. The Herdmans provided a shop, a dispensary, healthcare funded by penny weekly deductions from workers' wages (rising to sixpence by the 1940s), a Doctor's house and surgery built at Mill Lane in the late nineteenth century, and operated the village's own fire service. In the mid-1960s, following a slump in the linen industry, the company privatised the village by selling houses at prices ranging from £60 for the smallest to £120 for two-storey dwellings. Despite modernisation through recent decades, the terrace remains an important architectural group within Sion Mills, enjoying a good setting overlooking Church Square.