The Vivian Engine House on the right was constructed by Vivian & Sons between 1860 and 1862, to replace an earlier engine house located on the site. The new engine house contained a vertical steam engine used to drive a rolling mill, and it was substantially enlarged in 1910. The white, lime-washed building was built from dressed Pennant sandstone and grey – blue bricks manufactured at the copperworks itself. Behind the engine house is a tall tapering chimney stack constructed of red brick, which rests on an octagonal plinth.
The building on the left is the Musgrave Engine House. Both these buildings were surrounded by other buildings for most of their lives.