Building 22, former Joiner's Shop, including chimney and rebuilt boiler house (building 16)

This is a workshop with an integral engine house, dating from the 1850s and originally constructed for Earl Fitzwilliam. It was renovated in 1990 as part of the Elsecar Heritage Centre.

The building is constructed primarily of well-dressed, coursed sandstone with deep horizontal tooling, with a brick inner-wall facing and Welsh slate roofs. The plan incorporates a northern bay separated internally to form an engine house, now a stairwell, along with a rebuilt boiler house and chimney attached to the north. An upper floor is accessed via an external stair to the southern end, while the ground floor entrance is also at the southern end, and wide-arched entrances are located in the side walls.

The exterior is two storeys high, hipped, and measures three bays wide and eight bays long, with the wider northern bay (engine house) abutting the south-western corner of the adjacent Fitting Shop. String courses are present at first-floor and eaves height. Windows are regularly spaced, featuring slab lintels, projecting sills, and mostly diamond lattice iron window frames. Basket-arched ground-floor entrances, with iron-plated keystones, occupy the central three bays of the workshop section. An eastern elevation shows a round-arched window to the first-floor of the engine house bay, previously a doorway, with an inserted doorway located below. An inserted first-floor taking-in door, complete with a winch, is also present on the eastern elevation. A cantilevered stone staircase leads to a central first-floor doorway with a round-arched fanlight at the southern end. Ground-floor openings on the eastern side are now blocked internally.

The ground floor retains cast and wrought iron fittings attached to the ceiling beams. On the upper floor, within the partition wall dividing the northernmost bay (the former engine house), is a low-set, arched opening, now blocked, thought to have been used for a belt or rope drive. A lever mechanism, set higher in the same wall to the west, may have allowed disconnection of part of the power-train from the engine. Timber hooks are fixed to the exposed queen post roof structure.

The boiler chimney is stone-built and abuts the northern wall of the building, also bordering the nave wall of the Fitting Shop. It features a tall square base rising to a cornice just below the eaves line, then tapers to an octagonal shaft with a bold, corniced cap. A single-storey, gabled toilet block, built around 1990 and replicating the form of the original boiler house, stands between the Joiner's Shop and the Fitting Shop, filling the space around the chimney’s base.