He was taught as an architect in the Universidad Católica in Santiago and the Architectural Association in London. In 1993 he set up his own practice in Santiago. In 1999 he receives the AOA (Architecture Offices Association) award to the most outstanding young architect and was awarded at the Architecture Biennial in Chile. Teaches design studio at the Universidad Católica de Chile since 1994 and has taught as visiting professor in the Massachusetts Institute of Technology (USA, 2007) and the Università IUAV di Venezia (Italy, 2016, 2020). His projects have been published worldwide in specialized magazines, among them: Casabella, Arquitectura Viva, ARQ, and A+U. Practice work has been exhibited locally and abroad. Recent exhibitions include XV Chilean Architectural Biennial, Venice Biennale, Shenzhen and Hong Kong bi-city Biennial where he received the Public Choice Award and the Milan Triennial where he exhibited and ideal city for Africa. Irarrázaval has been awarded twice at the WAVE International Workshop held at IUAV in Venice (Italy, 2014-2015) and has been shortlisted for the Mies Crown Hall Americas Prize (USA, 2016) and the Architecture Swiss Award (Switzerland, 2017). Recently his project 2Y house was chosen among the best 3 projects of the year by Archdaily and his latest project Public Library of Constitución has been granted Merit at the AZ Award (Canada, 2016), Honor at the Wood Design and Building Award (Canada, 2016) and RIBA Award for International Excellence (UK, 2017).  Recently Irarrázaval has been awarded Eeero Saarinen Honorary Lecturer by the Museum of Finish Architecture (Finland, 2017) and Riba International Fellowship by the Royal Institute of British Architects.