The office of Francesc Alegre i Roig is connected to both the front room and the office of his administrator, where the safe was kept.
The entrance to this section, of frosted glass, is engraved with the escutcheon of the Alegre de Sagrera family.
It is a high-class office with a wooden wall bench that runs around the entire room as far as the impost. Above, the wall is covered with the same cloth as that used for the curtains of the window, which looks out onto Carrer de la Font Vella.
The hydraulic flooring is a reproduction of the original one in Casa Escofet, Tejera i Cia., in Barcelona, designed by the architect Josep Font i Gumà.
The original office furniture has not survived. The exhibited furniture comes from another home in Terrassa. It is the Elizabethan style of the latter half of the 19th century.
When the house was converted into a museum in 1973, it was decided to decorate it with items from the municipal heritage.