The purpose of the thesis work is to investigate what is required for thermal cracks not to occur and how these cracks can get minimized. A major part of the work is how thermal cracks affect the design and the consequences they can cause in production, but also in the projecting. In order for the work to get as wide as possible, it was decided that a literature study, interviews and a survey of a reference object would be conducted. The literature study contributed to a background in the work and why thermal cracks occur. The reference object further explained how thermal cracks are handled in practice. The interviews later contributed to the opinions from clients, projecting and production about thermal cracks. And where there are uncertainties and potential for improvement in the subject. The results the thesis was concluded in. Often do multiple actions be taken at the same time for thermal cracks should not occur. To say which action that is the most time and cost effective is unfortunately very difficult as there are so many different factors that matters. It needs to be made clear who is responsible for thermal cracks. It is also useful if the projector of thermal cracks is included from the start. In production thermal cracks contributes to a longer construction time. Unfortunately, today there is a lack of knowledge in the area. The conclusions that can be drawn from the thesis work are. That its needed to be a better knowledge about thermal cracks. Saying which action against thermal cracks that is the most cost effective is very difficult. To get opinions about what action is preferable benefits all involved parties.