Son of the master builder J. Granell i Mundet, he played an important part in Modernisme as an architect and as a promoter of the decorative arts. He qualified as an architect in 1891 from the Barcelona School of Architecture.

He represents a strand of Modernisme, closely linked to Art Nouveau, that became more important from 1900 onwards, when it started to manifest itself with a greater profusion of ornamental elements on the façades, such as stained glass windows and sgrafitti, and on the staircases inside buildings.

His main clients were the new inhabitants of Barcelona's Eixample district and most of his work is to be found in this area, including Cases Rossend Capellades (1904-1906; Bailèn, 126 i 127). One of his most representative buildings is Casa Granell (1902-1904; Gran Via de les Corts Catalanes, 582), which has often been attributed to his grandfather, the master builder Gerónimo Granell i Barrera.

At the end of the 19th century he entered into a partnership with the stained glass window maker A. Rigalt, and together they set up Rigalt, Granell i Cia, a company that lasted well into the 20th century. From 1914 onwards he cut back on his work as an architect and concentrated mainly on the stained glass window firm, making designs for sgrafitti and supports, including some for Escofet, Tejera i Cia.