Life-cycle assessment (LCA) is currently one of the construction industry’s most widely used methods of environmental assessment. Because LCA calculations is based on life-cycle thinking are the lifespan of the building a sensitive parameter in relation to the calculated overall environmental impact of the building. More accurate assessments of the lifespans of buildings are therefore a prerequisite for reducing errors and uncertainties in LCA and Life Cycle Costing (LCC) calculations. This study evaluates a generalized logistic lifespan prediction model for existing building typologies. The model is tested as part of a Danish case study based on building data collected from 124,096 cases of demolition. The objective is to investigate whether the typical lifespan used in LCA or LCC calculations accurately describes the remaining service life of existing buildings based on different building typologies and construction periods. The study show that office buildings generally have much shorter expected lifespans than previously assumed and that multi-family housing has nearly twice the lifespan of single-family housing. The results show a tendency for a declining lifespan based on the construction period, in which newer buildings, i.e. those that are no more than thirty years old, have a lifespan that is much shorter than the average lifespan for all construction periods. These results are highly relevant for both LCA and LCC calculations of buildings since they indicate that newer buildings in northern Europe have a lower lifespan than previous studies have shown.