The following text is from the original listed building designation:
FRINDSBURY EXTRA CP UPPER UPNOR TQ 77 SE 15/8 Upnor Castle House GV II
House. Mid C17 to north with late C18 garden front to south. Red brick to north, yellow brick to south with slate hipped roofs. Garden front: 2 storeys with coped brick parapet. 3 flat-headed dormers and stacks to rear. Regular 5 window front, glazing bar sashes, with wide tripartite sash in centre of first-floor and segmental-arched recess below with half-glazed door flanked by narrow windows. Entrance front: 5 complex gables, that in centre shaped over 2 storey porch.
Listing NGR: TQ7572470567

English Heritage, List of Buildings of Special Architectural or Historic Interest (Map). SKE16160.