His sober style reached full development in buildings like the Monastery of San Lorenzo de El Escorial.

His Discurso sobre la figura cúbica (Discussion of the Cubic form) tells us about his notable knowledge about geometry and mathematics.

Stylistically, he changed the image of the façades and introducing his personal sober style in accordance to the wishes of King Philip.

The main keys of his design are the impressive horizontal unified composition and the use of bare granite, omitting the classical orders for large surfaces.

As instructed in his 1584 will, after his death, his sepulchre was transferred from Madrid to the Church of San Juan Bautista in Maliaño, Cantabria.