He began his training in his father's cabinet-making workshop. At the same time, he took sculpture classes at La Llotja, the Barcelona School of Fine Arts, and attended a course to become an architect's assistant.

In 1905 he made his first trip to Cuba, but it was not until a year later that he settled there, living in Havana where he became one of the most active architects of the time. A year later he set up Taller de Fundición de Cemento, a factory that received a lot of publicity in the local press and became one of the leading suppliers of architectural items, mainly plaster mouldings and artificial stone for the buildings in the city. Gradually he broadened the scope of his activity to include designing buildings and interior decoration. At first his plans were signed by the architect Alberto de Castro and later by another architect, Ignacio de la Vega, with whom he worked on a house called L'Ampurdà (Revolución, 152, Havana, 1919; now Andrés González Lines school), a work whose interior decoration is reminiscent of Gaudí and in which Casa Pujol i Bausis was involved. Rotllant i Folcarà acquired his prestige largely due to his work in designing façades and funerary monuments.

His early works show the influence of the architects L. Domènech i Montaner and J. Puig i Cadafalch, as well as Franco-Belgian architecture and Viennese Sezessionstil. It is from this period that buildings such as Palacio Díaz Blanco (1910; Belascoaín, 1058 - Clavel y Santa Marta, Centro Habana, Havana) and Casa Juan Fradero (1910; Cardenas; Apodaca y Gloria, Old Havana), date. The design of these works features two characteristic elements: the projecting balconies with small columns and the ceramic domes. Many scholars consider his Casa Damaso Gutiérrez (1913; Patrocinio, 103, Havana) as the finest example of Modernisme in the area.

In 1914 he started to evolve towards more sober forms, although he retained the ornamentation in a Modernista style more closely akin to Art Nouveau. In 1919 he sold the workshop to his brother and returned to Barcelona, where he worked in the company founded by I. Mas i Morell and Joan Albadell, SA Construccions. Four years later he returned to Havana, but in 1925 he came back to Barcelona for good and remained active there until his death.