In this retrofit project by Tonkin Liu, a steel-framed water tower has undergone a dramatic transformation to become a part-time residence for photographer Dennis Pedersen and his family.

Mass timber, in the form of a compression spiral staircase and CLT rooms, is used to bring stability and strength to the delicate steel frame. This allowed the original character and structure of the water tower to be maintained, whilst creating a unique, liveable space.

First used on an airfield in Great Massingham, the water tower was relocated to just outside the village of Castle Acre in 1952. With a ruined Norman castle, an 11th century abbey and a Bailey gate, Castle Acre was already home to three notable ruins – and over time the water tower became its fourth.

After standing as a locally beloved landmark for seventy years, the tower was saved from the scrap yard when it was bought at auction by the clients. Now reinvented as a delightfully peculiar home, the water tower continues its life at the edge of the village.

Tonkin Liu’s design for the Water Tower sought to create strong connections with nature and setting. Through their intervention, the rusty water tank has become a living room, with a seemingly gravity-defying window cut through to the horizon. Stacked honey-coloured wooden bedrooms overlook the barley field, accessed from the stabilising spiral stair tower by a glass treetop bridge.

Alterations to the structure were minimised and existing steel was reused as much as possible. Responsibly sourced timber rooms were built within the steel frame, and a timber cantilevered spiral staircase provides access as well bringing stability and stiffness to the original structure.

Low air permeability, high levels of insulation, and MVHR heat recovery ensure low in-use carbon. Operational energy is minimized for the building, and improved by solar panels on the roof. In summer the stair tower acts as a thermal chimney to avoid overheating.