A first major stage of capital repairs takes place after 1919, when the spa system in Băile Herculane is reorganized, from an administrative point of view, with some interventions and repairs to the existing spa establishments.
The subsequent physical transformations that the building underwent were mainly carried out in the period after 1930. It should be noted that not all transformations / modifications were made in accordance with the existing structure of the building.
Between 1933 and 1934, the Ministry of Labor, Health and Social Protection proposes the resumption of works regarding the modernization of the Herculaneum Baths, through the project “New works at the Herculaneum Baths”.
In 1967 and after it, more extensive repairs were made, including reinforced concrete elements to the original existing structures.
Thus, at the left end of the Neptune Baths, a portion of the existing floor is replaced with a reinforced concrete slab. Also, at the two annexes, repairs and consolidations were made with reinforced concrete floors and pillars.
The most important transformations brought to the building took place in 1968, within the project entitled “Arrangements and modernizations at the Neptune Bath pavilion” and in 1971, within the project entitled “Capital Repairs Baia Neptun”. During this period, the building came under the tutelage of the “Spa and Tourism Enterprise” Herculane, which is also the beneficiary of the projects.
According to the existing archive data at the Caras-Severin County Directorate of National Archives, it presents the project from 1968, regarding the arrangement and modernization of the Neptune Bath Pavilion that occurred due to the degradations made by the inhabitants of the building during the war. According to the note made at that time, the temporary occupants of the building did not take into account the function of the building and destroyed the ventilation systems, which led to the undisturbed degradation of the building.
Within the Neptune Baths Capital Repairs project, 1971, both exterior and interior works were ordered. The exterior works refer to the complete restoration of the building facade, by removing the ceramic layer of the apparent bricks and applying ceramic tiles, in order to maintain the original architectural style. Works were also registered on the rear façade of the building, to which glazed plasters were applied. The retaining wall behind the building, being 80% collapsed, was rebuilt along the entire length of the building, with a height of 2 meters. Also within the Exterior Capital Repairs project includes the restoration of the tin roof with the dome ornaments, the change of the sheet was made in proportion of 50%, respecting the original style. Exterior joinery has been completely replaced. The rainwater drains were connected to the thermal water collection channels, with discharge into the Cerna River. Regarding the interior modifications made in 1971, there are: restoration works of the painting on the ceiling, in the same style, also the statuary group in the hall is reconditioned, the plasters with stop water were removed and redone on all interior surfaces. , the faience plywood in the cabins was changed, and the interior paving was made of white marble. Even the interior carpentry has been completely replaced. The wastewater drains have been overhauled and repaired. Also within the Capital Repairs project at Baia Neptun, the change and reconditioning of the electrical installation were taken into account. More precisely, the cable that supplied the building directly from the transformer station was changed, as well as the copper connectors at the connections along the building. The indoor electrical installation was dismantled and rebuilt into buried-mounted PVC pipes, and the switchboards were rebuilt accordingly. The entire project amounted to an investment value of 1,500,000 lei.