Construction is a crucial sector in terms of worldwide environmental impacts. Building material production along with transport and demolition are no exception, because in the last decades, they have constantly increased their carbon dioxide (CO2) emissions. Actions and initiatives are therefore important to tackle the relationship between buildings and climate change. Particularly, it is necessary to develop Life Cycle Assessment (LCA) tools useful to calculate the environmental impact of buildings and to make them accessible to designers and stakeholders acting in the building sector. The article aims to contribute to the international debate about environmental assessment indicators for buildings and the simplified LCA based tools. The Embodied Energy (EE) and the Embodied Carbon (EC) have been investigated. The former, related to primary energy content; the latter, associated with the equivalent carbon dioxide emissions. EE and EC have been used as indicators for the development of a calculation tool named EURECA, for assessing the environmental impact of the building over its life cycle, as defined by the EN 15978:2011 standard. The Solar Decathlon Latin America and Caribbean’s house designed and built by an international academic team has been an opportunity to check the indicators and the tool’s effectiveness.