I took a look at all 5 census that James Powney was recorded on.
1841 - born in County Durham
1851- born Elvet, Durham City
1861 - born Haswell
1871 - Durham City, St. Oswald's
1881 - Langley
Excluding the 1841 census the 1851 and 1871 Census are in the majority. Plus as James' father John was a Papermaker that requires water and facilities to make paper. Durham City had both. It is also possible that the "New Houses" were named after Bishop Thomas Langley who surely would have lived in Durham City when he was actively the Bishop.