Boilershop

The Boilershop is a disused dry dock cover, now serving as a boilershop, built in 1847 by Fox Henderson & Co at Woolwich Dockyard and re-erected at Chatham around 1876. It features a cast- and wrought-iron frame with corrugated-iron cladding and roof. The building has a rectangular plan with lower aisles and is a single-storey structure consisting of an 11-bay range and a 3-bay west extension. The gabled ends have raking aisles, with the frame expressed externally, and include a louvred ridge and moulded gutters. There is an irregular scattering of small windows along the sides, and lower brick additions have been made along the sides. At the west end, there is a decorative square clock tower with clocks on each face, topped with a louvred octagonal cupola and finial.

Inside, the building has a rigid iron frame supported by cast-iron columns and wrought-iron roof trusses, with aisles featuring segmental-arched cast-iron braces and pierced spandrels. Historically, covers for ship-building dry docks were introduced around 1814 to protect wooden ships during construction from the weather. The original structure was cast and erected at No.4 slip in Woolwich and was re-erected at Chatham by convict labour after the closure of Woolwich in 1865. This building represents a significant advancement in the development of rigid metal-framed structures and established the principle of portal bracing through stiff joints. It forms part of a fine group with the No.8 Machine Shop, which was also moved from Woolwich, and the timber and metal slip covers in Chatham Dockyard.