St John's church is located on the west side of Odo Street, facing down Graham Street. A Vivian benefaction, it was built in 1878-80 in Perpendicular style to designs of architect H.Woodyer of Guildford. The church is constructed of snecked rubble facings with Bath stone dressings under slate roofs. Its plan consisted of twin aisles to nave and east end, with undivided chancel and nave, south organ chamber/vestry, south aisle, west bellcote and south entrance. To the west is evidence at the end of the south aisle for a tower that was never built.
The interior opened out into two equal seven-bay spaces separated by an arcade of octagonal piers carrying four-centred arches. Roofs are of arch-brace and collar-beam type, trusses twice as closely spaced over the chancel as over the nave. There are also horizontal metal ties, part of the original design. Fittings include stone font and pulpit, both designed by Woodyer. Stained glass included work by A.K.Nicholson (1928).
In 2001 the building was sold off for conversion to social housing but still retains an area for worship.

Sources:
Extracts from Cadw Listing description.
J.Newman, Buildings of Wales: Glamorgan (1995), p.609-10.
http://www.walesonline.co.uk/news/wales-news/church-wales-land-sell-off-plan-2525594

RCAHMW, 19 May 2015