Nave and chancel church of several periods. The W gable of the church has antae and incorporates a Romanesque doorway with a gabled porch.

The first church here was founded in 622 by St Lachtain. The earliest surviving part of the church is the western part of the nave which originally formed a single cell structure with eastern and western antae. In the 12thc. the Romanesque porch was added to the west gable, presumably in an attempt to raise the status of the monastery. From the early 13thc. the bishops of Ossory had their summer palace at Uppercourt, close to Freshford. The church was extended further eastward probably in the 15thc. with an extension to the nave, and the addition of a chancel. Extensive works were carried out to the church in the 1730s, and it is probably at this time that at least part of the porch and doorway were dismantled. The upper gable of the porch was completely removed to facilitate the addition of a large window above, lighting the new gallery within. The church was further renovated in the late 1860s, probably by architects Welland and Gillespie, who replaced the 18thc. W window with a neo-Romanesque, circular window, capped the antae with neo-Romanesque pellet ornament and reinstated the gable of the porch.

Fragmentary inscriptions survive at Killeshin and Mona Incha, but the portal at Freshford is the only Romanesque monument to retain a complete inscription, although the builder and patron commemorated in the inscription cannot be historically identified. The barrel-vaulted porch is unusual in Ireland; the only other comparable example being the N porch at Cormac's Chapel, Cashel. The capitals of the inner orders of the portal can also be most closely paralleled with the N porch at Cormac's Chapel (c. 1134), while the structure of the portal, with its continuous, relatively plain inner order is closer to Clonkeen, Limerick, and Aghadoe, Kerry (c. 1158). This would seem to place the porch c.1140s. The sculptural decoration includes motifs found at a number of different sites, chiefly in Munster and Leinster. A similar step-pattern is found on the doorways at Aghadoe and Killeshin, and on the fragmentary remains of a doorway at Clonattin, Wexford. The use of a human head on the keystone is a common feature in Ireland, found at Killeshin, Clonkeen, Ullard (Kilkenny), Kilmore (Cavan), St Caiman's, Iniscealtra (Clare), and the N porch at Cormac's Chapel. The pseudo-scallop capitals are closely paralleled at Cormac's Chapel, and capitals with angle heads bitten by animals are also found at Cormac's Chapel, St Saviour's Glendalough (Wicklow), and Dysert O'Dea (Clare). The chamfered moulding with pellets used on the label and imposts is paralleled at the Nuns' Church at Clonmacnoise and Rahan (Offaly), Donaghmore (Tipperary), Killeshin (Laois), Ullard (Kilkenny), Kilkenny cathedral fragments and Kilmore (Cavan).

The unusually elaborate figure sculpture is probably not in its original location. The pair of figures on the R jamb of the inner order have obviously been cut down from their original size to fit the recessed panel, while a section of frame stops abruptly on the R porch panel, with two figures suggesting that this panel originally formed part of a longer narrative frieze. It seems likely that there may originally have been more scenes, possibly occupying the gable, removed in the 18thc. (Moss, 2000). Narrative sculpture is also found (reset) at Ullard (Kilkenny) and Liathmore (Tipperary), together with the better-knowm frieze sculpture at Ardmore (Waterford). Rachel Moss suggests that the incised crosses on the W doorway are later medieval consecration crosses.