There appears to be a blocked out window.
Window tax was introduced in England and Wales in 1696. It was repealed in 1851. Suggests the building was built before 1851.
We know from the
map that AlanBoyd posted earlier, surveyed in 1848, that the previous structure was the Blind Indigent Schools which the current Nos 28, 30 and 32 might have formed part of, probably the main entrance to the School. However by the 1851 census number 32 was a separate, self contained dwelling. The occupants were Morgan Radcliffe 48 a ship's carpenter, his wife, daughter, son, an assistant and an apprentice. I haven't been able to find the 1861 occupant, but by 1871 John Lloyd aged 41 Draper plus 13 draper's assistants or domestic staff are occupying 32 London Road and Joseph Naylor and family are at number 30, tying in with the directory entries Shaun posted. In 1861 John Lloyd 31 Draper's Assistant and his wife Ellen were living at 121 Park Road, West Derby.