Butting against the north-east side of the strongroom, the rectangular pill box air raid shelter has off-form concrete blast walls, a concrete slab floor and flat roof. It has entrances at the north-east and south-west ends, each with an open porch sheltered by the cantilevered roof. Only the north-east end retains its interior concrete blast wall, which forms an entrance corridor into the main space of the shelter. The floor and ceiling are coved and there are three openings to the north-west and south-east sides housing pairs of eight-light casement windows. Original toilet cubicles remain at each end of the building. The exterior and parts of the interior are painted. A metal framed communications mast sits on the roof of the shelter, but this is not of cultural heritage significance.
