San Mattia Apostolo is a later 20th century parish church with a postal address at Via Renato Fucini 285, north of the Via Nomentana in the east part of the district of Monte Sacro Alto. The main entrance is on the Via Alvaro Corrado. Pictures of the church on Wikimedia Commons are here.
The dedication is to St Matthias.
The parish was erected in 1964. Its church was designed by Ignazio Breccia, and completed in 1969. It is his only church in Rome.
As befits its period, the church is a spectacular Brutalist design in raw concrete, low and of one storey.
The plan is of a half-open fan, except that the frontage is straight not curved. The head of the fan is behind the altar, and the plan is made up of seven fan-leaves radiating from this.
Attached to the left hand side wall is a a semi-circular baptistery. Abutting the right hand wall is one wing of the parish headquarters, which comprises three wings around a courtyard mostly occupied by a ferial chapel on a rectangular plan. This is a completely separate edifice from the main church, but it abuts the far wing of the parish complex.
The edifice is in poured reinforced concrete, with the shuttering marks left showing. Structurally it has several autonomous elements which are self-supporting.
The best way to begin a view is to look at the altar end, which is accessible via a gate on the Via Renato Fucini. Here there are seven truly massive rectangular concrete piers on the plan of a V occupying the head of the "fan", with their major axes pointing down the leaves of the "fan" in the plan. These piers have battered (sloping) outer faces, and ascend in height to the tallest central one. In between the piers are narrow vertical window strips. The outermost piers have another pair of strips running up their outer sides, and beyond these are the ends of the exterior side walls of the church.
These piers support the far (altar) ends of the roof components. These consist of seven huge concrete troughs, narrowing in width as they approach the far end of the church. They also share a longitudinal curve, which is fairly steeply down from the altar end and then rises more gently towards the entrance. This feature is obvious in the view from the Via Renato Fucini.
In between the troughs are skylight strips, extensions of the window strips behind the altar.
The side walls are in blank concrete. The baptistery is a semi-circular apse attached to the left hand wall, in front of which is a side entrance. This entrance is accessed via a curving set of stairs sheltered by a curving screen wall -the curve echoes the wall of the apse on the other side of the stairs.
The near ends of the seven concrete roof troughs are supported by a transverse row of massive longitudinal slab piers within the main entrance. Unlike the arrangement at the far end, where each pier supports one far end of a trough, here the near end of each trough is supported by two piers. There are therefore eight of these piers, the middle six being double and the outer two single.
The roof troughs float forward in front of their near set of support piers. A concrete screen wall is inserted under them here, creating the church façade, and the troughs project further to create a sheltering canopy. The entrance arrangements are asymmetric:
The second and third troughs on the left project further than the rest, and under these are a pair of doorways. A third doorway is under the far right hand trough, which also projects. The first and fourth troughs from the left project the least, and the fifth and sixth troughs project a little more but not so much as over the entrances.
The side walls of the church also project, and are simply chopped off vertically. The entrances are flanked by vertical concrete slabs, with battered (sloping) outer edges.
Ferial chapel Edit
In stark contrast to the main church, the separate ferial chapel is a red brick box showing its concrete frame, having a flat roof with a parapet. The interior has red brick walls and a flat white ceiling -this is not a very interesting building.
For the church, what you see on the outside you get on the inside -raw concrete. The shuttering marks on the bottoms of the roof troughs give the odd impression that the roof is in wood. The seven skylight strips joining with the seven window strips behind the altar are symbolical of the Seven Sacraments.
The floor is of high quality, using square blocks of porphyry in imitation of the cobbled streets of the Centro Storico. The colour contrasts nicely with the light grey of the concrete.
Mass is celebrated (parish website, July 2018):
Weekdays 7:30 (not summer), 8:30, 18:30;
Sundays and Solemnities 7:30, 9:30 (not summer), 10:30 (10:00 summer), 11:30, 12:30 (not summer), 18:30.
"Summer" here is July to September.