Alternativa grundlösningar till betong vid byggnation av småhus.En jämförelse av olika husgrunder ur hållbarhet- och fuktperspektiv

Sammanfattning: The construction industry today is responsible for approximately 3-4% of the global carbon footprint, which is mainly due to the production of cement, one of the main components of concrete. The substitution of concrete for more sustainable, circular and biobased materials has become more prominent when it comes to the construction of buildings in general. However, concrete is completely dominant when building house foundations.  When society strives for a sustainable future, the construction industry must adjust and build more sustainable. The carbon footprint of concrete must decrease or be replaced completely by an environmentally friendly material but still maintain similar capacity. Reinforced concrete can currently be replaced by materials such as wood when building other construction components, however it is hard to replace in the foundation. This makes it appropriate to explore different alternative foundation methods. Therefore, the goal of this study is to investigate different established or conceptual foundation methods that could potentially replace concrete foundations when constructing smaller buildings. Examine their potential and limits and assess whether the methods can compete with reinforced concrete today. A literature study and interviews has been carried out.  The three different studied methods involve, Foam glass foundation (Koljern), wood foundation and ground screw.    Wood foundation is still a conceptual method which in theory should work. Although there are risks involving using organic materials such as wood when constructing a foundation, considering the soil stores water. Foam glass foundation (Koljern), combined with steel beams is a Swedish technology developed to replace reinforced concrete foundations for smaller buildings. It is a waterproof solution produced to minimize the environmental impact of house foundations.  Ground screw is an environmentally friendly option developed to maximize effectiveness building foundations. The ground screws are screwed directly into the ground carrying the weight of the building and keeping it off the ground. This means no preparatory work of the ground needs to be carried out. Mainly produced for smaller constructions such a decks and sheds, however there are possibilities to build larger constructions, such as houses.  The results of the data that has been compiled from various scientific studies and the interviews that were carried out, showed that there are no real competitive foundation methods to concrete regarding the three main aspects studied.