Icehouse, Costerton House

The icehouse at Costerton House dates from the mid-18th century and features a cap and dome design. It has an ogee entrance and an arched passageway that leads to a top-loading domed ice chamber. The exterior is constructed with ashlar stone, featuring long and short rybats with margins, while the interior consists of squared rubble that is partly lime rendered and whitewashed.

On the principal elevation, the entrance doorway has an ashlar lintel and long and short quoins. The walls are made of harled coursed rubble, with ogee-shaped wing walls; the left wall is full size, while the right wall is set into the natural hillside. There is a stone step leading into the entrance passage.

Inside, the high arched entrance passageway is lime harled and limewashed, leading to a smaller rectangular doorway designed for an inset door. This connects to a narrow rectangular passage and another doorway that leads to the domed ice chamber. The chamber features an exposed squared rubble circular dome with a central square top-loading flue and a later metal ventilator pipe on the rear wall. Inset stones for shelving are regularly placed around the walls, and the original floor level has been filled with dirt and rubble, with a central drain present. There were originally three doors, but all are now missing.

On the exterior, the icehouse is situated on a mound and has a square tooled ashlar top-loading flue, although the copes are disarrayed. There is also a round metal ventilating flue at the rear.