Hangar 3 at former RAF West Raynham

A Type-C Aircraft Hangar with annexes housing stores, workshops and offices, constructed between 1936 and 1939 to Air Ministry drawings 5053/36 and 5054/36.

The building is principally constructed of 14-inch reinforced concrete walls with a steel roof structure covered in asbestos slates. The plan is arranged with the long side elevation facing the flying field. At each end are full-height steel doors running to external gantries. The side elevations house annexes on the flying field side for squadron offices, and on the other side for workshops and stores.

The roof is concealed behind a parapet with a later metal balustrade. It comprises a series of transverse ridges with hipped ends, covered in asbestos cement slates. The long side walls are built of plain concrete with a slightly bush-hammered surface. At mid-height are 10 large window openings separated by concrete piers, with late 20th-century glazing replacing the original Crittall multi-pane casements. One bay at each end, also in concrete, is slightly brought forward in a Moderne manner with a higher parapet; a tall single light with horizontal bars is centred to each bay. Facing the flying field, a very large number 3 is painted centrally at parapet level.

The end elevations have six full height and width steel doors with replacement glazing at the top, under a deep projecting rail which carries the rolling headgear. Beyond the opening a light steel lattice beam projects out and is carried by a light steel strutted support with ground-stops for the doors. Above the doors, contained by the wing walls of the first bays, there is a deep apron with hanging asbestos-cement slates. At the western end a roller shutter has been inserted between the opened doors, which are otherwise fully retained.

The annexes on the long side elevations have steel casement windows. The southern office annex has a two-storey central section. At the western end of the office annex a small concrete-walled porch has been added. The northern workshop annex has an additional post-war storage area added at the western end, and an element of industrial plant added at the north-east corner. The central entranceways through the north and south annexes have had rubber swing doors added to the portals.

The principal interior space, the hangar itself, is twelve bays long and has no structural subdivisions. Some free-standing units have been created within the hangar as part of the building's 21st-century use as a manufacturing business. The complex lattice of roof girders is clearly visible, along with the roofing boards above it. There are four gantry cranes with surviving mechanisms at bays 2, 6, 7 and 11, capable of carrying either 1.5 tons or 6 tons as indicated by surviving signage. The steel structure supporting the roof is buried in the reinforced concrete walls, except for additional structural support in each of the end bays. The floor is formed of plain concrete. At the north-east end of the interior an inspection pit remains within the floor, covered with movable metal beams.

Access to the annexes is gained through multiple doorways on the north and south sides of the building. Centrally on each side are massive metal fire doors which originally led directly outside, and now lead to enclosed spaces.

The northern annexes originally housed workshops, stores and storage tanks. They have undergone various other uses since then, but retain much of their original layout as well as heavy metal doors, radiators and windows.

The southern annexes, facing the flying field, were originally intended to house squadron offices. Mid-20th-century speaker systems survive in these parts. Some historic partition walls survive, along with retained doors, windows, tiled cills and original radiators. The upper storey of the office annex is reached via a concrete staircase with a steel balustrade and oak handrail, similar in design to other Moderne balustrades found in the Station Headquarters and Officers' Mess. On the east side of these upper rooms, one window has massive metal hinges suggesting a pair of large shutters once hung there. An internal window into the hangar from the upper storey of the office annex has been blocked. Gun cabinets with mesh fronts survive on both floors.