This paper focuses on science laboratory design and the relationship with pedagogical practices. In 2007, the Portuguese Ministry of Education launched the Secondary School Modernisation Programme, involving the renovation of 332 schools. The SSMP includes the definition of a set of principles concerning the renovation of different spaces. Regarding labs, the decision was to adopt a different model of space design, based on the work of the British Association for Science Education. From research, conducted from 2010 until 2011 in 13 schools renovated within the framework of SSMP (Veloso et al. 2011), we have concluded that the labs are, in fact, the most controversial and debated of all the learning spaces, particularly by teachers. Our conclusions are based on: documental analysis, survey of pupils and teachers and focus groups with pupils and teachers while visiting schools. The issues raised here centre on the decision to change the lab physical model with the intention of inducing changes in learning practices: i) teachers were not involved in the discussion of the new model; ii) architects had very little intervention on the labs’ design, because it was a unique model applied across schools; iii) the importance of actors’ appropriation of the physical space.