Buildings are responsible for significant environmental impacts throughout their life cycle. To quantify these impacts, life cycle assessment (LCA) is used. The interpretation of LCA results in a wider context can be supported by comparing with benchmark values. For developing such benchmark values, two approaches exist. In a bottom-up approach, benchmarks are obtained from reference buildings, representing the environmental performance of conventional construction practices today. In a top-down approach, benchmarks are derived by translating global environmental goals, such as the planetary boundaries, to target values for buildings. In Belgium, both approaches were recently applied to develop life cycle environmental benchmark values for typical Belgian residential buildings. In both studies, the benchmark values were derived for all environmental impact indicators recommended by the European Environmental Footprint method and the EN 15804+A2 standard. This paper compares the bottom-up and top-down benchmark values of all indicators resulting from both studies. First, the top-down benchmarks are revised so that they apply to the same functional unit as the bottom-up benchmarks. Then, the comparison of both benchmark types reveals for which indicators new Belgian residential buildings exceed the carrying capacity allocated to them. Specifically, it shows that this is the case for five out of 15 indicators assessed. For climate change, for example, the bottom-up reference value is around 6.5 times as high as the top-down target value. The main drivers causing high environmental impacts for the five indicators are operational energy use for heating and hot water, as well as embodied impacts from conventional building materials, such as concrete and fired clay bricks. Given that the gap is extremely high for some indicators, a combination of various ambitious mitigation measures is needed to achieve the environmental targets.