Clash detection is a significant benefit of using a BIM software packages like REVIT. Traditionally design drawings had to be coordinated to ensure that different building systems do not clash and can actually be constructed in the allowable space. BIM software enables the Architect, Structural Engineer and Mechanical Engineer to resolve potential problems early in the design phase and crucially before construction begins on site. REVIT was used to do this for building 500 for GSK (GlaxoSmithKline) in Montrose.