The so called “ByggaF-method” is a relatively new Swedish method to stop moisture from being built into a building. The method should prevent damages on buildings as a result of mould growth and moisture. The purpose of the method is to include moisture control in the entire construction process, from the projecting phase and all the way to the management phase. Up until now, there is no proof if the method is profitable or not and no studies have been made on the topic. Therefore the rationale of this study is to show if a part of the method is in fact profitable from a financial point of view. The study is based on a renovation project of a building from the 1960 s in the outskirts of Stockholm. The building went through a major renovation 2006 which was poorly executed and led to major indoor environment problems. The current property owner consequently wanted the new renovation to be executed in a highly secure way from a moisture control point of view. One part of the method is that there is a full time moisture safety inspector at the construction site who ensures that the moisture control plan, which has been established during the projecting phase, is followed. Any deviation from this plan is documented and a deviation report is made. The study is based on these deviation reports. The reports have been analysed and calculations have been carried out to estimate the cost of the potential damages that could have occurred if the deviations had not been detected. This has led to a figure on how profitable the method really is.