Casa Convalescència is a unique building rich in Art Nouveau elements. It has a surface area of 6,245 m2 distributed over four floors and a basement. In structural terms it maintains the Catalan Art Nouveau tradition of ceilings comprised of brick vaults and metal girders that tense the flattened arches, made of bare-brickwork rowlock arches.
The monumental entrance leads into the vestibule, where the columns and capitals are made of natural stone, the arches and walls of bare brickwork and the banisters, parapets and balustrades are made of artificial stone. There are four murals with polychromed tiles that tell the story of the families that donated funds to build the old Casa in carrer del Carme: the coats of arms of the Gualba, Astor and Soler and Ferran families. The latter, expressed through a motif of a six-nailed horseshoe, is repeated on the floor tiles of the building in memory of the main benefactor of the first Casa de la Convalescència.
On the ground floor, all the rooms are decorated with banisters of majolicas, and tiled soffits are also conserved. These were manufactured in factories in Esplugues and Manises and depict the legends of the virtues of Faith, Hope and Charity and other religious allusions. The stairs that lead to the upper floors are made of marble or calcareous stone.
The former chapel, now the Aula Magna, has a markedly vertical proportion with a large dome in the centre sustained by shells, bare-brick rowlock arches and polished stone columns. The original high altar boasted an extraordinary altarpiece representing Saint George. It was made of Baroque-like sculpted alabaster, with spiralling columns and a multitude of decorative embossed work.