What is a roundhouse?

A roundhouse refers to a specialised building, typically found in larger rail depots, designed for housing and maintaining locomotives. Its most distinctive feature is its circular or semi-circular shape, which allows locomotives to be easily stored and serviced. At the centre of the roundhouse is a turntable, a rotating platform that enables the locomotives to be directed into various storage or maintenance bays. This design was particularly useful during the steam era when locomotives required frequent maintenance and could not easily reverse without a turntable.

The roundhouse was an essential part of a railway's infrastructure during the height of steam railways, providing a space where locomotives could be inspected, repaired and stored when not in use. The turntable allowed efficient movement of locomotives, minimising the space needed for individual tracks leading to maintenance sheds. By rotating the turntable, locomotives could be positioned in any available bay, making the roundhouse a highly functional and space-efficient solution for railway depots. This design was especially prevalent in larger rail hubs where multiple locomotives were in constant use and needed to be quickly turned around.

In Britain, roundhouses were commonly found at major railway depots throughout the steam era, but many fell into disuse or were demolished as diesel and electric locomotives became more common. These newer locomotives, which do not require turning, diminished the need for roundhouses, as they could operate in both directions without needing to be rotated. However, some historic roundhouses have been preserved as part of railway heritage sites, showcasing these once-essential buildings to the public.

From a model railway perspective, including a roundhouse in your layout can add an extra layer of authenticity, particularly if you're focusing on a steam-era theme. The roundhouse not only provides a visually striking feature but also enhances the operational realism of the model. With a functioning turntable, modellers can recreate the movements of locomotives as they are brought in for servicing or turned around for their next journey. A roundhouse also offers a practical way to display multiple engines in a compact space, adding depth to the overall scene.

One of the most famous roundhouses in the UK is the Derby Roundhouse, located in Derby, Derbyshire. Built in 1839 by the North Midland Railway, it is the world's oldest surviving roundhouse and played a crucial role during the early days of the British railway system. Designed by the renowned railway engineer Francis Thompson, the Derby Roundhouse was part of a larger complex of locomotive workshops and became an important hub for maintaining and servicing steam engines during the 19th century.

The roundhouse featured a central turntable, which allowed locomotives to be directed into any of the surrounding bays for maintenance or storage. The innovative design enabled efficient use of space and provided shelter for several locomotives at once, ensuring that Derby’s busy railway operations ran smoothly. As steam gave way to diesel and electric locomotives, the need for roundhouses like the one in Derby diminished, and the building eventually fell out of use as a railway facility.