# An Expert Knowledge-Based System to Evaluate the Efficiency of Dry Construction Methods
## 4 Discussion and Conclusions
By simulating through the complex COMBINATOR, it was possible to analyze the potential of dry construction against traditional wet construction in relation to the time, costs, weight, and labor intensity of individual techniques and systems of finishing works. Several conclusions were drawn based on the results of the simulations. By choosing only dry systems and techniques, the construction time can be reduced by between 40% and 80% of the days of construction with only wet works. In the construction of partitions, ceilings, wall finishes, and floors in residential buildings, when combining wet and dry construction techniques, the construction time can be reduced by 12% when choosing at least one dry system or technique, and by 50% when choosing three dry systems and techniques. In terms of construction time, the potential of dry finishing works was confirmed. By choosing only dry techniques, construction costs will increase by at least 12% and at most by 43% of the cost of wet construction systems and techniques. When combining wet techniques together with dry ones, by choosing at least one work made by a dry technique, the costs can be below the level of the costs of wet systems and techniques; by choosing three construction works made by dry techniques, the costs can reach a 36% to 39% increase compared to wet technologies. The potential in terms of costs was not confirmed, even though there were combinations of dry techniques that achieved competitive or more favorable costs compared to wet construction systems and techniques. By choosing only dry techniques, the weight is reduced by at least 50% to 80% of the weight of wet finishing works. Weight reduction is already demonstrated when choosing at least one work made by a dry technique (reduction max. 30%); when choosing three dry works made by dry techniques, the structural weight of partitions, ceilings, wall finishes, and floors may be reduced by 60% compared to wet techniques application only. The potential of dry construction in terms of weight has been clearly confirmed. By choosing only dry techniques, labor intensity will increase by at least 16%, and a maximum of 57%, of the labor intensity of wet works. By choosing dry systems and techniques, the labor intensity of finishing construction works increases; by choosing one work made by dry technique, the labor intensity increases by at least 9%; by choosing three, labor intensity increases by a maximum of 54%. The growing labor intensity due to the implementation of dry techniques requires more skills, which are subsequently reflected in the increase in the costs of dry construction. Some research studies have dealt with advantages as well as the obstacles to the greater use of dry construction [50; 51; 52]. In the study presented, the potential and competitiveness of dry construction in relation to traditional wet construction techniques was demonstrated by two-criteria optimization of the selection of combinations of systems and techniques for the finishing works of partitions, ceilings, wall finishes, and floors in a reference example of a family house. Based on the almost identical results of the two-criterion optimization of the selection of techniques for finishing works in residential buildings and family houses with the assignment of criteria weights (construction time criterion, construction cost criterion) in the presented study, some conclusions and recommendations for clients can be drawn. If the client prefers a short construction time (with a weight of time criterion from 55% to 100%) when making a decision, dry construction is more efficient and advantageous. If they prefer lower costs in their decision-making (with a weight of cost criterion from 75% to 100%), wet construction is more efficient and advantageous. If they are hesitative (50%/50%), then the construction methods for finishing work are comparable and competitive; dry construction even has a slight advantage.