Eglwys Oen Duw

The interior is faced in red brick, with freestone dressings, black and yellow brick below the cornice, and a frieze of encaustic glazed tiles below sill level. The floor is laid with decorative and encaustic tiles, which are richer in the chancel. The W window has a shafted rere arch. The nave has a 4-bay arched-braced roof. At its E end is a 2-centred arch supporting the tower, on pairs of Purbeck marble shafts with stiff-leaf capitals, that stand on wide corbels enriched with dog-tooth friezes. Beyond this is the chancel arch, which has 2 orders of chamfer, the inner order dying into the imposts. Directly beneath the tower is a narrow wooden imitation rib vault.

The chancel has a roof of closely-spaced arched braces. Its brick walls have similar polychrome enrichment to the nave, except that the E wall has a gold mosaic reredos with the legend 'Alleluia'. The E window has marble-shafted rere arches with stiff leaf capitals. The trefoil-headed piscina has a hood mould, marble shafts, and a diaper infill of polished stones set diagonally.

The large and heavy square font has a stepped base, round stem with attached shafts at the corners which have superimposed scalloped and waterleaf capitals. The bowl has a frieze of roundels with relief carvings of foliage and symbolic devices. Beside the font are damaged fonts brought here from the churches at Llanfihangel Abergwesyn and Llanddewi Abergwesyn.

The polygonal pulpit is of wrought and cast iron on a brick and stone base. A tier of fret-cut panels is below a tier of cusped arches. The hand rail is brass. The choir stalls have carved foliage to the ends and open quatrefoils to the front. The communion rail has iron uprights and a wooden hand rail.

Several windows have stained glass. The E window, by Clayton & Bell c1868, shows scenes from the Life, Passion and Resurrection of Christ in early French style. In the chancel S wall are 2 windows of c1877 by Burlison & Grylls, both dedicated to Clara Thomas and in late-medieval style. The SE window shows the descent of the Holy Spirit, the SW window shows the Adoration and Christ's baptism. In the chancel N window is an Ascension, which is unsigned. In the nave the W window, also c1868 by Clayton & Bell, depicts Gospel scenes and the Communion of Saints. The remainder of the nave glass is unattributed. In the N wall, at the E end, is a scene showing the Good Shepherd and commemorating Thomas family children who died in infancy in 1836 and 1838. Next to it is a window of c1907 to Margaret Lloyd showing 'Charity'. At the E end of the S wall is a window showing Christ with 2 small children, commemorating infant deaths of 1858 and 1860. In the porch W side window is glass by Anna Beasant dated 1999.

Early English style church of snecked, rock-faced stone with lighter freestone dressings, and steep tile roof behind coped gables. The nave has a S porch, with lower and narrower chancel. Over the E end of the nave is a slender shingled tower and spire, which has louvred bell openings, and a swept spire surmounted by an iron cross.

The porch, set back from the W end of the nave, has a 2-centred arch with double chamfer and no capitals, inside which are double doors with iron studs and flowing strap hinges. Small lancets are in the porch side walls. To the R of the porch are 2 lancets, then a third lancet in a shallow projection in line with the tower. The chancel S wall has a double, then a single lancet. The E window is 3 stepped lancets with a sill band with foliage stops. In the N wall is a single lancet, then a lower gabled vestry and organ recess. The nave N wall has 3 lancets, and a lancet in a shallow projection aligned with the tower, as on the S side. The W window has 5 stepped lancets.