Valleymount Church originally known as Blackditches was built in 1803. The church with its high pitched roof was quite plain in appearance, until Catholic emancipation in 1829 Catholic churches were unobtrusive.
All this was to change in the 1830's when the local stonecutters from Ballyknockan set to work on St Joseph's. They added the porch and above it a wall with a parapet which hides the pointed roof gable, on the roof line above the porch are four slender pointed pinnacles. A low wall separates the forecourt of the church from the road. It too is decorated with pinnacles and a tall granite cross rises above them. The cross commemorates a temperance mission conducted by Fr Matthew in 1846. In 1882 a baptismal font was made in the quarries, the marble altar was also a gift from the quarrymen.
The stained glass windows have been a feature of the church since the 19th century. They include Our Lady, St Joseph, St Patrick, St Brigid, Our Lady of Good Counsel, Christ the Good Shepherd.
In the 1930's a local move began to commission glass from Irish artist Harry Clarke. Two of his windows are placed in each transept, in the north The Sacred Heart and St Therese of the Child Jesus, to the south Our Lady Queen of Heaven and St Anthony. An important window shows Pope Pius x who was canonised in May 1954. The three windows behind the altar with their marvellous deep colours of purple, blue and red are the work of Hubert McGoldrick. They were made for the church of St Andrew in Clontarf. These windows were installed in 1988 by the parish priest of the time - Fr Richard Cantwell. It formed part of the repairs and restoration carried out at that time. Fr Cantwell was also a dedicated historian and inside the church is a two page account of its history.
This account of the history of Valleymount Church is taken from an article by Christopher Moriarty which appeared in the March issue of the Sacred Heart Messenger.