The aim of using a briefing model is not only to capture client requirements in a systematic way, but also to be able to link these requirements to the design teams design model. By doing so, it becomes possible to systematically check design proposals against client requirements, which reduces the chance of design errors. To be able to do a clash control between brief and design, the spaces from the brief (as required spaces) have to be mapped with the spaces in the design model (as designed spaces). Once spaces are mapped, it becomes possible to make all sorts of comparisons. An obvious example is the comparison between the sizes and numbers of spaces. Likewise, the availability of technical elements in rooms can easily be compared. In a hospital project it will, for example, be useful to check whether specific rooms have the appropriate gas outlets.It should be said, however, that not all requirements can be checked that easily. Indoor climate requirements, for example, are difficult because such requirements relate to a multitude of design features (finishes, hvac systems, wall thickness, etc.), which makes direct verification difficult. In such cases, quality control has to take place in a dedicated simulation or calculation model. Brie\x1bng model Design model(as requireddata)(as designeddata) Building BuildingRoom A Room B Room C Room C Room B Room AMappingMappings between the brief and the designTo link a requirements model (the brief) to a design model, it will be necessary to make a mapping between the objects of both models, for example indicating that design object A corresponds with briefing object B.Once such a mapping has been made, the two models can be cross-checked. 137