North City Flour Mills, Cross Guns Quay, Dublin 7, Co. Dublin

It is not an obviously decorative structure; the brick voussoirs framing each window and the ashlar limestone doorcase are almost the only concessions to appearance in a design otherwise dictated entirely by function. That plainness is itself the point. This was a working mill, built to move grain and machinery, not to impress passers-by, and the few flourishes it does carry, the block-and-start brick reveals, the granite sills, the cast-iron tie-bars holding the walls together, read as the practical vocabulary of nineteenth-century industrial building rather than ornament for its own sake.

The building began as Mallet's Iron Mill before being converted to flour milling in the 1860s, when it took the name North City Flour Mill. Its construction, dated to around 1840, predates that change of use, and the fabric still shows signs of adaptation over time, including an upper floor rebuilt in random rubble limestone rather than the more careful squared stone below. For the Phibsborough area, the mill mattered less for its architecture than for its economics: it was a significant employer in a district that grew up around the Royal Canal and the industries strung along it. Standing beside the 5th Lock, with a canal bridge, railway bridge, and railway siding all within sight, it belonged to a working landscape of transport and processing rather than a purely residential one, and its bulk still marks that history even now that the building has been converted into apartments.

The round-headed window set into the advanced gable end, unusual against the square-headed openings elsewhere on the building, is worth a second look, as is the timber panelled door at the centre of the front, flanked by stained-glass sidelights added when the building was adapted for its current residential use. The mild steel railings along the canal side sit on an old rubble limestone plinth wall, a small detail that hints at how much of the original boundary survives even where the building itself has changed hands and purpose.