BIM dimensions
The idea of adding layers of information to the 3D model — time (4D), cost (5D) and beyond.
"BIM dimensions" is a shorthand for the layers of information a model can carry beyond its three-dimensional geometry. The 3D model describes what and where; each further dimension attaches another kind of structured information to those same objects, so a single coordinated model can answer questions about schedule, cost and operation.
The widely agreed ones are 4D, which links elements to the construction schedule (time), and 5D, which links them to cost. Beyond that, "6D" is often used for sustainability and energy information and "7D" for facility and asset management — but these higher numbers are not universally standardised, and different sources assign them different meanings, so they are best treated as informal labels rather than fixed definitions.
The value of the idea is conceptual: it reminds teams that the model is a database, not a drawing. The same BIM objects that carry geometry can also carry the data that drives planning, estimating and operation — provided that data is captured to a defined level of need rather than added indiscriminately.
Need this in practice?
Information Modelling →