Achieving a transition to sustainability and decrease the environmental impact of building is part of Sweden's sustainability goals. Authorities and policy makers have a big responsibility to promote and facilitate this transition, but how this is to be achieved is not as readily answered. Using the multi-level perspective on socio-technical transitions, this thesis investigates the conditions for sustainability transitions in Swedish building by learning from the case of earthen and straw home builders. Qualitative mixed methods research, including questionnaires and semi-structured interviews was carried out to explore drivers and barriers for innovative sustainable building in Sweden. Findings suggest that there are barriers for innovative sustainable building in Sweden that might slow down the sustainability transition process, not in terms of regulation but in practices and norms in the current socio-technical regime.