The purpose of this study is to compare a concrete slab on ground with a Koljernfoundation based on the given aspects of climate impact, cost, and time. The goal of the study is to identify obstacles and opportunities for the construction industry to use alternatives to concrete slab in new construction of low-rise buildings. Currently, the construction and real estate sector account for 20 % of Sweden's greenhouse gas emissions. Concrete and steel contribute significantly to emissions and are materials that are included in concrete slabs, which is why the Koljernfoundation which consists of cellular glas and steel studs could be one of the solutions required to achieve climate neutrality. To achieve the purpose, a literature study has been conducted to create an overview of the foundation’s structures. A case study has been made to investigate the three aspects, and interviews have been held. The results showed that a concrete slab has about twice the emissions of a Koljernfoundation for the A1-A3 product stage. Therefore, the conclusion is that the Koljernfoundation is the most suitable option for the foundation of a low-rise building from a climate perspective. The time aspect is investigated for the first time in this study and the results show that the Koljernfoundation can make the building process more time-efficient if there is no problem during the installation of the foundation. The results also show that for concreate slabs, the material cost is significantly lower than for the Koljernfoundation.