The stone used in construction was gray granite from Matallana for the facades, black slate for the roof, and stone from Girona for the sculpture of St. George on the main facade.

The structural work is metallic in the basement and on the ground floor, and wooden on the remaining floors.

The grating that surrounds the trench is made up of a series of helicoidally twisted and entwined iron plates, riveted to each other and to some T-profiles, with points at the top similar to the ones Gaudí designed for the Casa Vicens in Barcelona.

Gaudí was not in Leon very much, being absorbed by his research for the new structure for the Sagrada Familia, and by his assignment to build the Col.legi de les Teresianes. When he was not in Leon, Claudio Alsina visited the work site to implement his orders and keep him informed.

For almost forty years, the building, property of the Fernández y Andrés firm, was maintained without alterations. But, in 1931 the Monte de Piedad y Caja de Ahorros de Leon, which had acquired the building in 1929, performed some remodeling. The interior structure was not significantly changed, but the wooden overhead spaces on the ground floor and the central stairway to the basement were removed.

In 1953, the same savings bank decided to carry out a series of projects to modernize the basement, ground floor and main floor. Stairwells leading to the various floors of the building were eliminated, and some columns were removed to give the ground floor more free space. The distribution and decoration of the main floor were also changed.

In 1950, the sculpture of St. George at the main entry was quite deteriorated, and part of the dragon's jaw had fallen off, so it was obviously in need of restoration. At that time, the option of replacing the image of the patron saint of Catalonia with the Virgin of the Paths, patron of Leon, was considered. There were concerns and discussion about the change for some time, but finally, in 1953, it was decided to restore the entire original sculpture.

When the figure was removed, a lead pipe was found hidden in the pedestal, which contained floor and elevation plans signed by Gaudí and the owners, press from the period, manuscripts related to the property, the certificate of completion of construction, some sketches by Gaudí and drawings of details of the edifice. The names of all the artisans who worked on this building were learned thanks to one of these documents.

In 1992, Caja España agreed to perform a full rehabilitation of Gaudí's Casa Botines with the following objectives:

• Fortification of the edifice
• Recovery and reconditioning of the semi-basement floor
• Reestablishment of the ground floor as designed by Gaudí
• Revitalization of the main, first, second and third floors for representative offices
• Regeneration of the attic in order to create a space for the institutional leadership.
• Construction of a low-profile outdoor area, where the nucleus of new facilities and technical panels of the building could be placed.