Before qualifying as a National Monument, the Monastery was subject to conservation works, as reported by the DGEMN – Direção Geral dos Edifícios e Monumentos Nacionais [General Directorate for Buildings and National Monuments].
A wooden vault was improvised along the nave, a 17th and 18th centuries choir was recovered, and for a secure fitting of its beams, the masonry of the walls and the upper part of the door were mutilated.
The walls and vault of the chancel were plastered, and, for display of an ancient image of the church's patron saint, Saint Peter, the apex of the gable overlooking the porch was demolished, the door under the arch of the wall south was covered, and the access ladder, with stone steps to the tower, was replaced by another, outside, along the south façade, up till the bell gable.
After the classification, the Monastery was subject to interventions, under the responsibility of DGEMN – Direção Geral dos Edifícios e Monumentos Nacionais [General Directorate for Buildings and National Monuments], the first of which consisted of the demolition of the choir that was blocking the nave and covered part of the main door.
In 1930 the main altar and all other four altars in the nave were dismantled, the portico was uncovered, the modern pulpit was disassembled, the exterior ladder improvised along the south façade was demolished and the primitive ladder and respective door were cleared. We then proceeded to the demotion and paving of the floor of the nave and chancel, including the construction of the steps that separate the two bodies of the building, and to the general lowering of the floor of the narthex and around the churchyard.
That same period marked the beginning of the dismantling and reconstruction works in the entire frame of the roof, then in ruins, and of the vaulted wooden ceiling that had been covering the nave. The new roof was built and sat and the vault and cornice of the chancel were consolidated, in addition to replacing the old cover with a new one, with a double national tile.
In 1933 a compact stone altar was built, using the primitive elements found during construction, and in the chancel the two framed crevices, which had been widened for greater brightness, were reconstructed.
In the following year we proceeded to the demolition of eight large windows, which were replaced by the primitive crevices, resorting to the elements found during the works.
In 1936, the annex that had been built in the north façade, near the apse, was demolished and replaced by another with a smaller plant, the mutilated stonework on the interior and exterior walls of the church were replaced, the exterior doors were built and settled, and the stained glass, with lead frame, was put in place.
Before covering the door, which had been opened on the main façade to access the choir, made in 1950, the primitive steps of the main door were repaired, while demolishing a part of the walls of the narthex, which concealed the abacus carved in the main, in which the tympanum and the corbels that support it were placed.
Between 1950 and 1952, the image of the patron Saint Peter was restored to its original place in the chancel. We then proceeded to the reconstruction of gable on the wall of the main portico. That year also saw the cleaning and repairing of the roofs.
In that same period the stone wall that covered the primitive portico of the north façade would have been demolished, its steps were rebuilt and the lower stone of the tympanum was replaced.
The sill and the door steps of the south façade, which had disappeared, were also reconstructed, and the rosette on the posterior wall of the nave was reconstructed, under the triumphal arch. We then proceeded to the general cleaning of the mortar that covered the stonework in the nave, on the walls and in the vault of the chancel.
The cleaning and minor repair of the roofs also took place in 1952. Probably on an earlier date, a cross was constructed and settled on the end of the nave's posterior gable, after it had been dismantled and reconstituted.
A decade and a half later, the hardware in the exterior doors was repaired, the roofs were cleaned and the exterior wooden doors were painted with oil paint. Works for the general cleaning of roofs were also carried out, with replacement of broken and missing tiles, as well as the repair of casings and fences.
The roofing was refurbished in 1986, and ditch was excavated along the wall to prevent water infiltration. The covering was repaired in 1989 and the chancel was subject to an intervention, in 1996, alongside the review of the roof of the nave, the installation of electrical wiring and carpentry.
In 2000 the conservation works took place in the sacristy, including the execution of a new ceiling in chestnut wood, the designing and application of stained glass in the spans and the placing of a nozzle for water supply of the existing granite font.
Finally, in 2004, we preceded to the general preservation of the property, including the general revision of the roof of the nave, chancel and sacristy, exterior and interior batters, of the outer spans and the belfry, and the overhaul of the electrical wiring inside the church and bell tower.